Diabetes Prevention Program Feasibility Study of Breastfeeding
Phase: NA
Conditions: Pregnancy, Overweight and Obesity
Sponsor: University of Kansas Medical Center

 
 DPP Feasibility Study of Breastfeeding 
 
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Diabetes Prevention Program Feasibility Study of Breastfeeding 
 
 
Principal Investigator: Lisette Jacobson, PhD, MPA, MA 
 
Mentors: Tracie Collins, MD, MPH, MHCDS; David Robbins, MD; Judy Stern, PhD   
 
Key Personnel: David Grainger, MD, MPH; Kelsey Lu, MS; Meredith Lucas, BA; Hayrettin 
Okut, PhD; Niaman Nazir, MBBS, MPH; Michael Wolfe, MD; Rosey Zackula MA  
 
Consultants: Brenda Bandy, IBCLC; Jolynn Dowling, MSN, APRN, NNP-BC, IBCLC 
 
 
Version: March 25, 2019 
  
 
Section I. Purpose, Background and Rationale 
 
A. Specific Aims and Hypotheses 
In the proposed randomized controlled trial, we seek to determine the feasibility and efficacy of a 
combined breastfeeding, DPP-based program in a cohort of overweight/obese women to be 
followed during pregnancy through 6 months postpartum.  Our trial will have three study arms: 
DPP plus breastfeeding (Tx1); DPP Only (Tx2); and Usual Care (Tx3).  Specific aims are: 
 
Aim 1:  Test the efficacy of Tx1 to improve 6-month postpartum weight loss among women 
with a BMI ≥ 25.  We will measure maternal height and weight at baseline; weight at delivery 
and 6 months postpartum. 
Hypothesis 1: Women in Tx1 will have greater weight loss postpartum compared to women in 
Tx2 and Tx3.   
 
Aim 2: Test the efficacy of Tx1 to improve 6-month postpartum mean blood glucose 
(HbA1c) and mean arterial blood pressure among women with a BMI ≥ 25.  We will 
measure HbA1c and mean arterial blood pressure at baseline, delivery, and 6 months postpartum.   
Hypothesis 2: Women in Tx1 will have better HbA1c and mean arterial blood pressure 
postpartum compared to women in Tx2 and Tx3.      
 
Aim 3:  Test the efficacy of Tx1 to increase any breastfeeding through 6 months 
postpartum among women with a BMI ≥ 25.  We will measure any breastfeeding continuance 
at week 1, 3, and 6 postpartum, and at 3 and 6 months. 
Hypothesis 3: Women in Tx1 will breastfeed longer compared to women in Tx2 and Tx3.   
 
 
 
 

 
 DPP Feasibility Study of Breastfeeding 
 
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B. Background and Significance 
Gestational diabetes mellitus (GDM) affects between 6%1-3 to 20%2,4 of pregnant women in the 
United States.  Overweight and obesity are a major risk factor for GDM5-9 and also considered an 
independent risk factor for other adverse health outcomes.10-15  Women with a history of GDM 
have at least a seven-fold increased risk of developing type 2 diabetes mellitus (T2DM) 
compared to women who do not have GDM.16,17  Gestational diabetes is associated with 
increased maternal and neonatal morbidity and mortality.18-29  Complications of GDM are further 
increased for rural women who often experience limited access to obstetrical healthcare 
services,30-33 leading to poor birth outcomes34-36 and reduced breastfeeding rates.37      
 
Against this background, we completed a pilot health assessment in a rural southwest Kansas 
community with an alarming number of high-risk pregnancies complicated by gestational 
diabetes, 11% vs. 6% nationally.2  Half of respondents were Hispanic of low socio-economic 
status.38  During pregnancy, three-quarters of women were overweight/obese, did not exercise, 
and had a family history of diabetes.38  Further, findings from a qualitative follow-up study 
within this same community indicated that women had limited access to health promotion 
programs and breastfeeding services. 
 
Rural communities with limited availability of health promotion programs and potentially high 
rates of chronic disease face a myriad of problems.  First, diabetes is associated with adverse 
health outcomes for mother and child.  Women with GDM are at increased risk for pregnancy 
and delivery complications — including preeclampsia,18-22 cesarean section,18,19,22,23 pregnancy-
induced hypertension,20,23,28 preterm birth,19,20 shoulder dystocia,18,20,24 and macrosomia18,20,22-
27,29 — leading to increased maternal and neonatal morbidity and mortality.18,24,29,39  Infants born 
to mothers with GDM are more likely to have neonatal hypoglycemia,26,40 hyperinsulinemia,26,40 
and are at greater risk for developing metabolic syndrome,41 diabetes,42 and obesity during 
childhood/adolescence.43-45  Second, having a pregnancy complicated with GDM and residing in 
a rural location is particularly challenging due to limited access and availability of healthcare 
services.46-51  Specifically, rural pregnant women have a higher likelihood of low birth-weight 
babies and pre-term delivery,30,34-36 high smoking rates,37,52 and reduced breastfeeding rates.37  
Due to geographic barriers, high rates of chronic disease including obesity, and limited 
availability of health promotion programs coupled with a demonstrated need for health behavior 
change, it becomes important to test an intervention during the prenatal and postnatal period 
among this at-risk population. This period is particularly conducive to behavior change because: 
(1) women are more likely to modify their behavior to benefit their children, (2) behavior change 
interventions are most successful in the short term, and (3) effective interventions that start 
during pregnancy are more likely to be sustained after birth, thereby reducing the risk of 
retaining excess weight and maternal obesity.53,54   
 
Given the demonstrated need for health behavior change, it is worthwhile to test the use of an 
intervention during the prenatal and postnatal period.  The Diabetes Prevention Program (DPP) is 
associated with a reduced risk of developing T2DM by 58% through counseling on effective 

 
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diet, exercise, and behavior modification.55  There is also evidence to support the use of this 
efficacious program in reducing postpartum weight.56,57  Further, recent evidence suggests that 
longer duration of breastfeeding is associated with lowering T2DM incidence,58-61 reducing 
maternal postpartum weight,62-64 and resetting maternal metabolism after pregnancy.65  
Breastfeeding also protects against breast cancer,66 ovarian cancer,67,68 and T2DM.69,70  Despite 
these findings, no studies have addressed the role of intensive breastfeeding support combined 
with an efficacious weight loss program to reduce postpartum weight, thereby reducing 
progression to T2DM after pregnancy. 
 
The American Academy of Pediatrics71 and the World Health Organization72 recommend 
breastfeeding for the first 6 months of life.  In Kansas, 79%73 of women with a BMI ≥ 25 start 
breastfeeding, and only 29%73 still breastfeed with some supplementation (defined as “any 
breastfeeding”) at 6 months postpartum.  The Kansas rate for high BMI women of 29% is 
unacceptable and an urgent public health concern when compared to the 6-month breastfeeding 
rate for normal BMI Kansas women of 51% and the Healthy People 2020 goal of 61%.74  In the 
proposed randomized controlled trial, we seek to determine the feasibility and efficacy of a 
combined breastfeeding, DPP-based program in a cohort of overweight/obese women to be 
followed during pregnancy through 6 months postpartum.  Our trial will have three study arms: 
DPP plus breastfeeding (Tx1); DPP Only (Tx2); and Usual Care (Tx3).  A total sample of 60 
pregnant women in their 1st or 2nd trimester with a BMI ≥ 25 will be recruited. Eligible 
participants are randomly assigned to a study arm (20 per arm). 
 
C. Preliminary Studies 
I led and completed two pilot studies in southwest rural Kansas: (1) a health assessment of the 
obstetrical population (completed in April 2015), and (2) a follow-up focus group study with the 
same population (completed in May 2016).  The purpose of the assessment was to learn about 
the health behaviors of rural pregnant women.  Two local hospitals and one federally qualified 
rural health center participated in the assessment.  Our sample consisted of 177 rural pregnant 
women.  Key findings indicated that the majority of women were Hispanic (50.3%), 18-25 years 
old (48.6%), high school educated (51.2%) , WIC enrolled (51.7%), and earned < $25,000/year 
(54.2%).38  The majority were overweight (28.1%) or obese (26.2%) prior to pregnancy, which 
increased to 34.4% and 41.6% respectively during pregnancy.38  Additionally, the majority 
engaged in no daily exercise (72.6%) and nearly one-third (30.5%) reported having an immediate 
family member who was diagnosed or treated for diabetes or cardiovascular disease.38  These 
results demonstrate significant diabetes risk factors during and after pregnancy.  Subsequently, in 
follow-up to the assessment, I led and completed a focus group study to gain in-depth 
information from this same population on what they would value in a health promotion program.  
Findings indicated limited availability of programs that focus on exercise, diet, and breastfeeding 
support during and after pregnancy.  Further, I published three additional studies relevant to the 
proposed project.37,52,75  Each of these studies focused on health behaviors among urban versus 
rural WIC enrolled women in Kansas and helped our research team understand the prenatal and 
postnatal needs of at-risk populations in Kansas.  These studies also provided me with 

 
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experience in collaborating with other researchers and with the process of publishing a 
manuscript in a high-impact professional journal.    
 
D. Rationale for Proposed Study 
Risk factors for diabetes are well documented.5-9  Maternal obesity in particular increases the risk 
of negative health outcomes for mother15,76-80 and child,81-86 including the propensity for women 
to retain excessive postpartum weight leading to obesity in subsequent pregnancies.87-90  Less is 
known about protective factors relevant to diabetes though evidence suggests that longer 
duration of breastfeeding among women with a history of GDM is associated with lower 
incidence of developing type 2 diabetes up to two years after pregnancy.58-61  Breastfeeding also 
appears to lower maternal postpartum weight62-64 and facilitates the resetting of maternal 
metabolism after pregnancy.65  The Diabetes Prevention Program (DPP) is associated with a 
reduced risk of developing diabetes by 58%55  and there is evidence to support the use of this 
efficacious program in reducing postpartum weight.56,57  Despite these findings, no studies have 
used a DPP-enhanced version that includes intensive breastfeeding counseling and support for 
overweight and obese women.  Given that overweight and obese women at risk for GDM are 
also less likely to start and continue breastfeeding,84,91-93 it is critical that interventions for 
reducing GDM risk also include breastfeeding support that is uniquely tailored to the needs of 
this population.  This is where the current proposal narrows the gap and contributes to the body 
of knowledge about reducing diabetes risk factors during and after pregnancy in an underserved 
population with scarce healthcare resources available.  
 
E. Impact of Proposed Study 
The proposed project will inform future intervention efforts that aim to reduce diabetes risk 
factors during and after pregnancy and to increase breastfeeding, thereby improving short- and 
long-term maternal and child health outcomes.  The immediate impact will be to reduce diabetes 
risk factors among a high-risk population and inform interventions aimed at reducing these risk 
factors and decreasing disproportionate morbidity.  Its ultimate potentially high public health 
impact is GDM and type 2 diabetes prevention among a racially and ethnically diverse, at-risk 
population.   
 
F. Justification for Project 
Risk factors for diabetes are well documented,5-9 but less is known about some factors that 
attenuate the risk for GDM.  Recent studies support the use of the Diabetes Prevention Program 
in reducing postpartum weight.56,57  Moreover, emerging research suggests that longer duration 
of breastfeeding among women with a history of GDM decreases the likelihood of developing 
type 2 diabetes within two years after pregnancy.58-61  However, no prior studies have assessed 
the feasibility and efficacy of a DPP-based intervention that includes intensive breastfeeding 
counseling and support among racially and ethnically diverse reproductive-age rural women.  
Rural pregnant women in particular have decreased access to healthy foods and fewer options to 
engage in physical activity.94-98  Furthermore, Hispanic women often supplement breastfeeding 
with formula, triggering decreased milk supply and early breastfeeding cessation.99-101  The 

 
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proposed research is innovative because it represents a departure from what has been 
accomplished in the field thus far: We seek to implement a combined breastfeeding, DPP-based 
intervention and determine its feasibility and efficacy as well as its effect on metabolic outcomes 
among an at-risk population.  Through examination of postpartum weight, breastfeeding 
behavior, and metabolic markers, results of the proposed project will inform the development of 
interventions to reduce diabetes risk factors during and after pregnancy.  Furthermore, an 
efficacious approach toward promoting exercise, nutrition, and breastfeeding can be integrated 
into the continuum of healthcare services provided to racially and ethnically diverse, at-risk rural 
pregnant women. 
 
 
Section II. Research Plan and Design 
 
A. Study Design Overview 
This is a three-arm pilot randomized 
controlled trial (RCT) to implement as 
well as determine the feasibility and 
efficacy of an intervention that is based 
on the Diabetes Prevention Program 
and includes intensive breastfeeding 
counseling and support among a cohort 
of overweight and obese pregnant 
women.  Upon meeting eligibility 
criteria, participants will be randomly 
assigned to the DPP plus breastfeeding 
(intervention, Tx1), DPP Only (Tx2), 
or Usual Care (Tx3), and will be 
followed during pregnancy through 6 
months postpartum.  Participants in 
Tx1 will receive the DPP and targeted 
breastfeeding support during 
pregnancy through 6 months 
postpartum.  Participants in Tx2 will 
receive the DPP only.  Participants in 
Tx3 will receive care as usual.  Usual care is described as obstetrical care that women with 
normal BMI receive and that is provided by the same provider (Dr. Michael Wolfe).   
 
At recruitment and at study closure, participants will complete four survey instruments; each of 
which assesses women’s knowledge of physical activity, nutrition, and breastfeeding (see 
appendices 1 through 4).  Also, postpartum women will complete the Edinburgh Postnatal 
Depression Scale (EPDS, see appendix 5) and a study coordinator will assess postpartum 
women’s breastfeeding experience with the Bristol Breastfeeding Assessment Tool (BBAT, see 
Figure 1.  Study Design 
 
 
 
 
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appendix 6).  Weight, mean blood glucose (HbA1c), mean arterial blood pressure, and glucose 
tolerance levels during pregnancy as well as initiation and duration of breastfeeding will be 
measured for all participants through 6 months postpartum.   
 
B. Duration of Study 
It is anticipated that after receiving Institutional Review Board (IRB) approval, recruitment will 
begin during the last quarter of 2019 and will continue through June of 2020.  We will recruit 
over a period of 9 months and the last follow up with women will take place at 6 months 
postpartum.  The trial will be completed over a 24-month period and will conclude during the 
second quarter of 2021.  Data collection and preliminary data analysis will take place as the trial 
runs.  Final data analysis and dissemination of findings will all take place following completion 
of the trial, during 2021 and 2022.             
 
C. Number of Participants 
This IRB protocol pertains to the recruitment of eligible participants from two obstetrical clinics:  
one clinic at Via Christi Health (VCH), a regional hospital in Wichita, and another clinic at 
Kearny County Hospital, a full-service hospital in rural southwest Kansas.  About 45% (16,797) 
of Wichita’s Hispanic population is female and of reproductive age,102 and the VCH clinic sees a 
high volume of this at-risk population at an average of 123 pregnant patients per month, with an 
average pre-pregnancy BMI of 30.5 (personal communication by senior management staff at 
VCH on January 18, 2017).  These socio-demographic and health data are similar to those of at-
risk rural pregnant women in southwest Kansas who visit Kearny County Hospital (KCH) for 
prenatal and postnatal care.  Dr. Michael Wolfe, maternal fetal medicine specialist, sees pregnant 
women at both of these locations (VCH and KCH), and he and his staff will actively assist with 
patient recruitment.  Our goal is to randomize a total of 72 eligible participants (24 women in 
each study arm, which translates to 12 women from each recruitment site).  Our recruitment 
target of overweight or obese pregnant women will involve 50% Hispanic women (who are 
English-speaking) and 50% other race including non-Hispanic whites.  The population of 
pregnant women in southwest Kansas who deliver at Kearny County Hospital, Lakin, Kansas, is 
estimated to be 300 individuals, of which 75% (or 225 individuals) have a BMI ≥ 25 and < 35.  
  
D. Subject Selection Criteria and Recruitment 
We will recruit pregnant patients from two obstetrical clinics: one clinic at Via Christi Hospitals 
Wichita, Inc. (VCH), a regional hospital in Wichita, and another clinic at Kearny County 
Hospital, a full-service rural hospital located in Lakin, southwest Kansas.  Dr. Michael Wolfe, 
maternal fetal medicine specialist, sees pregnant women at this location, and he and his staff will 
actively assist with patient recruitment.  During the first prenatal appointment, Dr. Wolfe will 
screen potential participants for inclusion criteria, and if he believes a participant meets inclusion 
criteria (see Table 1), then he will familiarize a potential participant with the study’s purpose.  If 
the potential participant is interested in the study, then he will give her a study brochure and a 
hard copy of the consent form.  Prior to using this study brochure, the brochure will be reviewed 
and approved by the IRB at Via Christi Hospitals Wichita, Inc.   By providing the potential 

 
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participant with a copy of the consent form, this will serve as the verbal consent script. Dr. Wolfe 
will also provide the potential participant’s name and phone number to Dr. Jacobson and her 
research coordinator.  After receiving a potential participant’s name and phone number from Dr. 
Wolfe, the research coordinator will follow up with a phone call to determine if the potential 
participant again meets study inclusion criteria, and if she does, the coordinator will screen if the 
potential participant meets study exclusion criteria during the same phone call (see Table 1).  
Before the research coordinator screens for inclusion and exclusion criteria, during this same 
phone call, verbal consent will be obtained between the participant and the research coordinator, 
using the consent form as the verbal consent script, and then written e-consent will be obtained 
via REDCap at the orientation session.  Once the participant is enrolled in the study and over the 
course of her pregnancy develops one of the conditions mentioned under Exclusion (Table 1), 
then this will be reported to the Data and Safety Officer.  It will then be decided in consultation 
with Dr. Wolfe if the participant will be able to continue participating in the study or if she will 
need to be dismissed.      
 
 
If the participant meets enrollment 
criteria, then the research 
coordinator will call her again to 
assign her a time and place for the 
orientation session, to complete 
study-related survey instruments, 
and to obtain her email address to 
provide her with informed consent 
materials for review.  Participants 
are informed that they will earn 
incentives to continue and complete 
the study: (1) a $50 gift card at study 
entry, (2) a digital scale and 
pedometer at delivery, and (3) a gift 
up to $75 for baby at Walmart’s 
baby registry at study closure.  
Investigators will issue incentives in 
accordance with policies set forth by 
IRB (please refer to the heading titled “Self-Administered Surveys and Incentive to Participate” 
below for additional detail regarding participant incentives).  
    
Our recruitment target of overweight or obese pregnant women will involve 50% Hispanic 
women (who are English-speaking) and 50% other race including non-Hispanic whites.  We 
anticipate meeting our recruitment goals through multiple approaches.  We will promote the 
study via targeted mailings and clinic posters.  We will advertise and develop study materials in 
English only.  We will recruit over a period of 9 months, planning to randomize 2-3 participants 
Table 1. Enrollment Criteria
Inclusion
1.  Pregnant
2.  In 1st trimester or early in 2nd trimester
2.  BMI ≥ 25 and < 35
3.  At least 18 years old or older
4.  Be able to understand English
5.  Must have a cell phone
6.  Able to use Facebook
7.  Able to use Skype, FaceTime or Zoom
Exclusion
1.  Pregnancy complications that require emergency care  
2.  Thyroid disease 
3.  Multiple gestation
4.  Substance abuse within last 3 years
5.  ART (Assisted Reproductive Technology) pregnancy
6.  Current smoker
7.  Prior bariatric surgery
8.  In weight-loss program within 3 months of conception
9.  BMI ≥ 35
10. Unable to attend intervention/follow-up visits
11. Unwilling to self-monitor data collection
12. Unable to complete intervention
13. Presence of any condition that limits walking
14. Presence of any condition that limits following diet
      recommendations
15. Pregnancies complicated with fetuses diagnosed with
      lethal malformations/conditions

 
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each week, or 1-2 participants per site.  Our goal is to randomize a total of 72 pregnant women 
(24 women in each study arm, 12 women per site).  Given an attrition rate of 20%, this will leave 
us with 60 women total (20 women in each study arm, or 10 women per site in each study arm). 
 
E. Study Locations 
Recruitment will take place at two obstetrical clinics: 1) Via Christi Hospitals Wichita, Inc., 
Kansas, and 2) Kearny County Hospital, Lakin, Kansas.  We will have on-going support from 
both hospitals.  Michael Mullins, Senior Vice President, Ascension Healthcare and Laurie 
Labarca, Hospital President St. Joseph, Via Christi Hospitals Wichita, Inc. as well as Benjamin 
Anderson, Chief Executive Officer Kearny County Hospital, fully support Dr. Jacobson’s work 
to determine the feasibility and efficacy of a combined breastfeeding, DPP-based program in a 
cohort of overweight/obese women to be followed during pregnancy through 6 months 
postpartum (see their letters of support, Appendix 7-8).  Most importantly, we will have ongoing 
support for Dr. Jacobson’s work from Dr. Michael Wolfe, Maternal Fetal Medicine Specialist, 
who sees pregnant women at both locations (see letter of support, Appendix 9).   
 
Locations for each obstetrical clinic affiliated with the hospitals above are as follows:  
 
Kearny County Hospital 
 
 
Via Christi Maternal Fetal Medicine Clinic  
500 East Thorpe Street 
 
 
1515 South Clifton Avenue, Suite 130 
Lakin, Kansas  67860  
 
 
Wichita, Kansas  67218   
 
F & G. Methodology – Intervention, Study Procedures and Data Collection 
 
The Intervention 
Conceptual Model.  We will use Social Cognitive Theory (SCT)103,104 and Self-Determination 
Theory (SDT)105,106 to guide program development and selection of measures.  SCT stipulates 
that behavior modification results from the interaction between behavior change, cognition (self-
efficacy, perception of barriers to lifestyle changes), and the environment (support), while 
modeling and reinforcement serve to encourage change.  SDT is a broad-based theory of human 
motivation107 that explains how intrinsic motivation can lead to improved eating and exercise 
patterns.108  According to SDT, a person’s increased intrinsic motivation to improve eating and 
exercise patterns should positively relate to self-efficacy and the ability to overcome barriers and 
solicit support.  The DPP plus breastfeeding (Tx1) uses assignments, individualized goal setting, 
and shared problem-solving to increase mastery and goal achievement in incremental steps to 
enhance self-regulatory skills. 
   
Diabetes Prevention Program (DPP).  Dr. Jacobson and the research coordinator will 
administer the DPP in two phases.  Phase I consists of a total of 16 sessions that will be 
completed during pregnancy (see Table 2).  Two of the Phase I DPP sessions have been replaced 
with the Cooking Matters47 curriculum: DPP session #2 has been replaced with creating a 
healthy home food environment, and DPP session #4 with incorporating more fruits, vegetables, 

 
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and whole grains into family meals.  Cooking Matters empowers low-income families with the 
skills to cook healthy, affordable meals at home.  Its curriculum uses the Dietary Guidelines for 
Americans109 and MyPlate71 as the foundation for basic nutrition guidelines.  Each of the sixteen 
(16) sessions/modules of Phase I will be pre-recorded and archived on a secure, private group on 
Facebook.  Only Tx1 and Tx2 participants, Dr. Jacobson and the research coordinator will have 
access to this Facebook group.      
 
We will employ a “rolling” recruitment period of 9 months, meaning that each participant may 
be at different completion stages.  During their first face-to-face orientation session, participants 
will receive access to the secure, private group on Facebook.   They will be asked to complete 
each Phase I module on their own time, starting at week 19 of pregnancy.  To supplement their 
self-study of the curriculum, on a weekly basis, the research coordinator will follow up with each 
study participant via phone to check on progress.  If participants do not make adequate progress, 
then the coordinator will assess how much extra time the participant needs to complete a module, 
and will work with her face-to-face via Skype, FaceTime or Zoom if needed.  Participants will 
complete Phase I by week 33 of pregnancy.   
 
Phase II consists of a total of 15 sessions that will be completed after delivery (see Table 2).  
Two of the Phase II DPP sessions (sessions #4 and #5 respectively) have been modified with the 
Cooking Matters curriculum that (1) emphasizes planning/preparing for healthy, low-cost meals 
and (2) encourages mothers to make smart choices when food shopping.  Each of the fifteen (15) 
sessions/modules of Phase II will be pre-recorded and archived on the same secure, private group 
on Facebook mentioned above.  Only Tx1 and Tx2 participants, Dr. Jacobson and the research 
coordinator will have access to this Facebook group.      
   
Participants will re-engage into the DPP with another face-to-face orientation session conducted 
by Dr. Jacobson at week 6 postpartum.  The same session completion format and procedure for 
inadequate progress will be followed as during pregnancy.  Participants will complete Phase II 
by week 20 postpartum.   An 80% completion rate of each phase is considered successful 
completion of the intervention.    
 

 
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Breastfeeding.  Additionally, participants in Tx1 will receive an educational session on 
breastfeeding and will register for and participate in a professional peer support group (see Table 
3).  Participants in Tx2 and Tx3 will not receive breastfeeding education or register/participate in 
a professional peer support group.  The 2-hour breastfeeding session is pre-recorded into four (4) 
30-minute sessions and archived on the same secure, private Facebook group as mentioned 
previously.  Participants will have access to all four breastfeeding sessions by week 24 of 
pregnancy and they need to complete all sessions by week 30 of pregnancy.    The breastfeeding 
session will be taught by an International Board Certified Lactation Consultant (IBCLC).     
 
At delivery, all participants will receive some type of lactation support in the hospital.  However, 
only participants in Tx1 will be provided with a breastfeeding assessment at day 3, day 10, week 
3 and week 6, as well as months 2, 3 and 6 postpartum (see Table 3).  The breastfeeding 
telephone assessment is modelled after the Bristol Breastfeeding Assessment Tool (BBAT)110 
(see Appendix 6) and used to improve an infant’s positioning, attachment, sucking, and 
swallowing.  During these telephone assessments, Dr. Jacobson’s research coordinator will 
assess if mother and baby need breastfeeding support from a lactation professional.  If the 
telephone assessment warrants an in-person visit, then the research coordinator will put mother 
and baby in contact with a lactation professional provided by the hospital.     
 
Breastfeeding curriculum.  The Kansas Breastfeeding Coalition, Inc. (KBC) in partnership with 
the Kansas Department of Health and Environment (KDHE) Bureau of Family Health (Title V 
Table 2. Timetable - Diabetes Prevention Program Sessions
DPP Sessions - Phase I
Week of 
Pregnancy DPP Sessions - Phase II 
Week of 
Postpartum
1 -   Orientation - Welcome!
18
1 -   Orientation - Welcome Back!
6
2 -   Cooking Matters (CM): Set a Healthy Example
19
2 -   Fats: Saturated, Unsaturated, & Trans-Fats 
7
3 -   Eating Less Fat and Fewer Calories
20
3 -   Food Preparation & Recipe Modification
8
4 -   CM: Choosing Fruits, Vege's, Whole Grains
21
4 -   Taking It One Meal at a Time, CM: Planning
9
5 -   Move Those Muscles
22
5 -   Variety and Balance, CM: Shopping
10
6 -   Being Active - A Way of Life
23
6 -   More Volume, Fewer Calories
11
7 -   Tip the Calorie Balance
24
7 -   Staying on Top of Physical Activity
12
8 -   Take Charge of What's Around You
25
8 -   Stepping Up to Physical Activity
13
9 -   Problem Solving
26
9 -   Long-term Maintenance
14
10 - Four Keys to Healthy Eating Out
27
10 - Holidays, Vacations, Special Events
15
11 - Talk Back to Negative Thoughts
28
11 - Preventing Relapse
16
12 - The Slippery Slope of Lifestyle Change
29
12 - Stress and Time Management
17
13 - Jump Start Your Activity Plan
30
13 - Heart Health
18
14 - Make Social Cues Work for You
31
14 - A Closer Look at Type 2 Diabetes
19
15 - You Can Manage Stress
32
15 - Looking Back and Looking Forward
20
16 - Ways to Stay Motivated
33
Postnatal (Post-core Curriculum)
Prenatal (Core Curriculum)
Table 3.  Breastfeeding Support for Women in Tx1 (Intervention Arm) Only
Prenatal
Intervention Components
Week 24 - 30
Day 3
Day 10 3 Weeks 6 Weeks 2 Months 3 Months 6 Months
Breastfeeding Education (2-hour curriculum)
X
Breastfeeding Professional Peer Support 
Participants initiate contact
Breastfeeding Telephone Assessment (15-20 minutes)
X
X
X
X
X
X
X
Postnatal
Participants attend 2 to 4 sessions as needed

 
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Maternal and Child Health Services Program) created a 2-hour breastfeeding class for parents 
and parents-to-be.  The curriculum aligns with nutritional requirements set by the U.S. 
Department of Agriculture’s Special Supplemental Nutrition Program for Women, Infants, and 
Children (WIC) and with parenting and maternity care practices of specific Kansas-based 
organizations such as the Kansas Infant Death and SIDS Network, Inc.111 and the United 
Methodist Health Ministry Fund’s High 5 for Mom & Baby.112  Further, the curriculum is based 
on the Office on Women’s Health “Your Guide to Breastfeeding.”113  The content of the 2-hour 
session will focus on the following areas: establishing and maintain a sufficient and safe breast 
milk supply, breast anatomy and physiology, maternal diet and lifestyle choices, prescription and 
non-prescription medications, infant stomach capacity, baby behavior feeding cues, breast milk 
expression, safe handling and storage of breast milk, returning to work, safe preparation of infant 
formula, biologically appropriate bottle feeding, and local community breastfeeding resources.   
 
Potential survey participants will have the option of contacting researchers with any questions 
prior to completing the survey or prior to participating in the educational session, and will self-
administer the survey if wanting to participate.  Responses will be entered in REDCap for data 
analysis.  All identifying information will be removed from the data prior to analysis.  Research 
personnel will not have access to any identifying information contained in the survey.   
 
Self-Administered Surveys and Incentive to Participate.  All surveys will be self-
administered (Appendix 1 through 5 – Survey Instruments) and are available in English.  The 
pre- and post-survey instruments are identical.  They will be administered electronically at 
baseline (at study entry) and at six months postpartum (see Table 5 Data Collection).  Via email, 
the study coordinator will provide each participant with a REDCap link that provides electronic 
access to each survey.  Informed consent will occur when the participant opens the survey.  
Participants will self-administer the survey and may stop at any time.  Potential survey 
participants will have the option of contacting researchers with any questions prior to completing 
the survey.  The survey instrument will be set up using REDCap and responses will be 
automatically entered and stored in REDCap for data analysis.  All identifying information will 
be removed from the data prior to analysis.  Research personnel will not have access to any 
identifying information contained in the survey.   
 
At recruitment and at study closure 6 months postpartum, all participants will complete four pre- 
and post-survey instruments: (1) Breastfeeding assessment, socio-demographic characteristics, 
and health status (sociodemographic and health status questions will only be asked at baseline, 
not at study closure) (Appendix 1); (2) Breastfeeding Self-Efficacy Scale-Short Form (BSES-SF) 
(Appendix 1);114-117 (3) Kaiser Physical Activity Survey (KPAS) (Appendix 2);118,119 and, (4) the 
Eating At America’s Table Study (EATS) Fruit & Vegetable Intake Screener120-122 (Appendix  3) 
supplemented with questions on fiber, added sugars, dairy, calcium, and meat from the Dietary 
Screener in the National Health and Nutrition Examination Survey (NHANES 2009-10) 
(Appendix 4).123,124  Each instrument will take about 10-15 minutes to complete and participants 
are provided with adequate time (i.e., about 1 hour) to complete all surveys.  Additionally, recent 

 
 DPP Feasibility Study of Breastfeeding 
 
12 
 
evidence shows that higher BMI pregnant women may have an increased likelihood of postnatal 
depression.125,126  Therefore, at 6 weeks postpartum, all participants will complete the Edinburgh 
Postnatal Depression Scale (EPDS) (Appendix 5),127-129 which takes about 5 minutes.  
Participants with an EPDS score of 10 or higher will be referred to a mental healthcare 
professional for further psychological evaluation.  All study survey instruments are listed in 
Table 4.      
 
 
 
 
Each participant will receive a $50 gift card at consent, after she will deliver her baby, the 
participant will receive a digital scale and a pedometer, and upon completion of the study (at 6 
months after birth), each participant may select a gift up to $75 for their baby from their baby 
registry at Walmart. .  In summary, for participants randomized to any of the three groups: 1) 
DPP plus breastfeeding, or 2) DPP only, or 3) Usual care, the total possible compensation is 
valued at $187.50 including the following gift items: digital scale (valued at $50 each), 
pedometer (valued at $12.50 each), baby gift at Walmart (valued at $75 each), and a $50 gift 
card. 
If a participant ends early prior to completing the study, then she will only receive the items for 
the program components that she completed. 
 
Table 4.  Survey Instruments
Study Instrument
Items Measured
No. of Items
Reliability
Populations Validated
Breastfeeding Knowledge Assessment, Socio-
demographic Characteristics, and Health Status
To assess knowledge of 
breastfeeding (44 items), to 
assess socio-demographic 
characteristics (6 items), to 
assess health status (7 
items)
57 items; multiple choice, 
and Likert-type scale
Not yet performed.
Not yet performed.
Breastfeeding Self-Efficacy Scale-Short Form
(BSES-SF)
To assess levels of self-
efficacy in postpartum 
women.  BSES-SF has also 
been used with prenatal 
women.
14 items; 5-point Likert-type 
scale.
Crohnbach's alpha = 0.97
Postpartum women at 1 
week, 4 weeks, and 8 weeks.
Kaiser Physical Activity Survey (KPAS)
To assess multiple 
domains of physical activity 
and total physical activity in 
pregnant women.
38 items; 4 domains: 
household and family care 
activities, occupational 
activities, active living 
habits, participation in 
sports/exercise
Correlation coefficient for total 
activity: r = 0.84; correlation 
coefficient for multiple domains:
r = 0.76 - 0.86
Pregnant women aged 18 to 
47 years old.
Fruit & Vegetable Intake Screener (EATS)
To assess intake of fruits 
and vegetables.
10 items; with portion-size 
questions.
Correlation coefficient between test 
instrument and true intake:
r = 0.51-0.67
Correlation coefficient between 
three screeners: r = 0.52 - 0.71
Men and women aged 20 to 
70 years old.
Selected items from the Dietary Screener
Questionnaire (NHANES 2009-10)
To assess intake of fiber, 
added sugars, dairy, 
calcium, and meat.
Up to 6 selected items on 
fiber, added sugars, dairy, 
calcium and meat; DSQ has 
a total of 26 items.
Not yet performed.
Not yet performed.
Edinburgh Postnatal Depression Scale
(EPDS)
To assess levels of 
depression during the 
postpartum period.  
10 items
Sensitivity: 34-100%
Specificity: 44-100%
Positive likelihood ratios: 1.61-78
Antepartum and postpartum 
women.

 
 DPP Feasibility Study of Breastfeeding 
 
13 
 
Study payments are taxable income.  Prior to distribution of gift items and after obtaining 
consent, a form 1099 will be provided to each participant for completion.  This process is in 
accordance and in compliance with regulations set forth by the University of Kansas School of 
Medicine and the Internal Revenue Service if you receive $600 or more in a calendar year for 
participating in research studies.  
 
Section III. Statistical Methods and Data Analysis 
 
Study data will be managed using REDCap electronic data capture tools hosted at the University 
of Kansas School of Medicine – Wichita.19  REDCap (Research Electronic Data Capture) is a 
secure, web-based application designed to support data capture for research studies, providing 1) 
an intuitive interface for validated data entry; 2) audit trails for tracking data manipulation and 
export procedures; 3) automated export procedures for seamless data downloads to common 
statistical packages; and 4) procedures for importing data from external sources.   
 
Outcome Measures and Rationale for Outcome Measures.  The expected outcomes of this 
study are (1) to increase postpartum weight loss; (2) to improve HbA1c and mean arterial blood 
pressure; and (3) to increase any breastfeeding.  As this is a pilot trial, we will also collect the 
following data: number of women screened, number of women recruited and enrolled, number of 
women who withdraw from the study and reasons for withdrawal, number of women who 
complete the DPP protocol, and number of women who complete the breastfeeding sessions.  
Upon recruitment into the study and at study closure, all participants will complete the BSES-SF, 
KPAS, EATS, and selected items from the DSQ NHANES 2009-10 to assess differences in 
knowledge and self-efficacy toward breastfeeding, physical activity, and nutrition.  Table 5 
shows a timeline for data collection in all three study arms.  
 
Aim 1:  Test the efficacy of Tx1 to improve 6-month postpartum weight loss among women 
with a BMI ≥ 25.  Hypothesis 1:  Women in Tx1 will have greater weight loss postpartum 
compared to women in Tx2 and Tx3.  We will measure maternal height and weight as outlined in 
Table 5 below.  We will measure weight loss at the same time points as any breastfeeding 
because this will allow meaningful comparisons among the study arms.  
 
Aim 2:  Test the efficacy of Tx1 to improve 6-month postpartum mean blood glucose 
(HbA1c) and mean arterial blood pressure among women with a BMI ≥ 25.  Hypothesis 2:  
Women in Tx1 will have better HbA1c and mean arterial blood pressure postpartum compared to 
women in Tx2 and Tx3.  We will measure mean blood glucose and mean arterial blood pressure 
((systolic blood pressure +2 41/3)) as outlined in Table 5 below.  We will also collect baseline 
data on glucose tolerance levels during pregnancy.   
 
Aim 3:  Test the efficacy of Tx1 to increase any breastfeeding through 6 months 
postpartum among women with a BMI ≥ 25.  Hypothesis 3:  Women in Tx1 will breastfeed 
longer compared to women in Tx2 and Tx3.  At delivery, breastfeeding initiation will be 
measured (see Table 5).  This is defined as starting breastfeeding immediately after delivery.  We 

 
 DPP Feasibility Study of Breastfeeding 
 
14 
 
will also measure the duration of any breastfeeding (defined as predominant breast milk with 
some formula supplementation) as outlined in Table 5 below.  Further, we will measure 
exclusivity of breastfeeding (defined as exclusive breast milk without supplementation unless 
medically necessary), formula supplementation, and solid foods.  We will measure formula and 
solid food at the time that they were first introduced as well as quantity and frequency of 
feedings. 
 
 
 
Sample Size and Randomization.  The primary outcomes of interest are: (1) postpartum weight 
loss; (2) HbA1c and mean arterial blood pressure; and (3) breastfeeding duration.  A total of 60 
participants (20 per study arm) will be recruited.  The results from this pilot study will be used in 
sample size estimation for a future study that is sufficiently powered to detect a clinically 
meaningful effect size.  Due to the nature of this project being a feasibility study, the sample size 
in the proposed study is not based on providing adequate power to detect a clinically meaningful 
effect size across the three study arms.  Block randomization with block size of 5 participants 
will be employed.  A sequence of 12 random integers will be generated using a computer 
algorithm.  The first 4 integers of the sequence will be assigned to the DPP plus breastfeeding 
arm; the next 4 integers will be assigned to the DPP only arm; and the last 4 will be assigned to 
the usual care arm.  Blocks will be assigned to arms in the increasing order of sequence of 
integers generated.   
Statistical Analysis.  For baseline data characteristics, descriptive statistics will be reported as 
mean and standard deviation for continuous variables and as count and percentage for categorical 
variables.  Depending on the distribution of the continuous variables, the Kruskal-Wallis test or 
ANOVA will be used to test for differences in continuous variables across the three arms.  Chi-
Table 5.  Timeline: Data Collection for All Study Participants
Measurements
Baseline Week 24 Week 28 Week 32 Week 36 Delivery 1 Week 3 Weeks 6 Weeks 3 Months 6 Months
Breastfeeding Knowledge, demographics, health status
X
X
Breastfeeding Self-Efficacy Scale-Short Form (BSES-SF)
X
X
Kaiser Physical Activity Survey (KPAS)
X
X
Fruit & Vegetable Intake Screener (EATS)
X
X
Selected items from DSQ (NHANES 2009-10)
X
X
Mother's Weight (lbs)
X
X
X
X
X
X
X
Mother's Height (inches)
X
Glucose tolerance
X
Mother's HbA1c
X
X
Mother's Mean Arterial Blood Pressure
X
X
X
Baby's Weight (kg)
X
X
X
X
X
X
Baby's Height (gm)
X
X
X
X
X
X
Breastfeeding Initiation at Delivery
X
Breastfeeding Duration (any and exclusive)
X
X
X
X
X
Formula Supplementation
X
X
X
X
X
X
Solid Foods
X
X
X
X
X
Postnatal
Prenatal

 
 DPP Feasibility Study of Breastfeeding 
 
15 
 
Square test of independence (or Fishers exact test if 25% of cells have counts less than 5) will be 
used to assess the association between categorical variables and the three arms.  The analysis will 
be based on “intention-to-treat” principle.  A two-sided alpha level of 0.05 will be used to 
determine statistical significance.  A 95% confidence interval will also be reported. 
 
Aim 1:  Test the efficacy of Tx1 to improve 6-month postpartum weight loss among women 
with a BMI ≥ 25.  The outcome of interest is 6 month postpartum weight loss measured across 
the three arms.  Weight will be measured at delivery, and at weeks 1, 3, and 6 postpartum and at 
3 months (13 weeks) and 6 months (26 weeks) postpartum.  The difference in postpartum weight 
(weight loss) between two consecutive time points will be computed.  Thus, each participant has 
5 postpartum weight loss values based on weight measurements at 6 different time points.  We 
will use the generalized estimating equation approach to compare weight loss in the DPP plus 
breastfeeding arm (Tx1) with weight loss in the DPP only (Tx2) and usual care (Tx3) arms, as 
well as weight loss between Tx2 and Tx3.  The working correlation matrix will be specified after 
assessing the data.  The model will be adjusted for the effect of age, race/ethnicity, level of 
education, annual household income, family history of diabetes, baseline weight, pre-diabetes 
status, and parity. 
 
Aim 2: Test the efficacy of Tx1 to improve 6-month postpartum mean blood glucose 
(HbA1c) and mean arterial blood pressure among women with a BMI ≥ 25.  The outcome of 
interest is mean blood glucose (HbA1c) and mean arterial blood pressure ((systolic blood 
pressure +2 (diastolic blood pressure)/3)) measured at baseline, delivery, and at 6 months 
postpartum across the three arms.  We will use a multiple linear regression approach to compare 
HbA1c in Tx1 with HbA1c in Tx2 and Tx3, as well as HbA1c between Tx2 and Tx3.  The model 
will be adjusted for the effect of age, race/ethnicity, level of education, annual household 
income, family history of diabetes, pre-diabetes status, parity, and baseline weight.  The 
difference in mean blood arterial pressure at 6 months postpartum will also be assessed using a 
separate multiple linear regression approach after adjusting for the same covariates listed 
previously.  
 
Aim 3:  Test the efficacy of Tx1 to increase any breastfeeding through 6 months 
postpartum among women with a BMI ≥ 25.  The outcome of interest is breastfeeding through 
6 months postpartum; it will be measured at delivery, and at weeks 1, 3, and 6 postpartum and at 
3 months (13 weeks) and 6 months (26 weeks) postpartum.  The risk of stopping “6 month 
postpartum breastfeeding” in Tx1 relative to Tx2 and Tx3 will be estimated using Zou’s 
modified Poisson regression approach.130  The outcome in Zou’s modified Poisson regression is 
binary, and it does not take into account the time until which any breastfeeding was done before 
stopping.  However, it provides an interpretation-friendly estimate of the probability of stopping 
“6 month postpartum breastfeeding.”  Additionally, the Cox Ph model will be used to compare 
the risk (hazard) of stopping breastfeeding across each study arm.  Unlike Zou’s modified 
Poisson approach, the Cox model takes into account the time of breastfeeding.  Any participants 
who are lost to follow-up will be treated as censored events and participants who stop 

 
 DPP Feasibility Study of Breastfeeding 
 
16 
 
breastfeeding during the follow-up are the events of interest.  In addition, participants who 
performed any breastfeeding until 6 months will be treated as administratively censored events.  
The model will be adjusted for the same covariates listed above under Aims #1 and #2. 
 
Missing data.  Owing to the design of the study and non-transient nature of the study population, 
we anticipate few to none missing observations.  Any missing observation that can be attributed 
to either attrition or nonresponse will be considered missing at random. Depending on the 
proportion of missingness, complete case analysis (less than 5% missing) or the multiple 
imputation method will be used to impute missing data. For longitudinal response (postpartum 
weight measurements), the last observation will be carried forward to impute the missing 
response. Results based on imputed data will be compared to findings from complete case 
analysis, to assess the effect of missingness on study findings. 
 
Comparison of scores on the Breastfeeding Assessment, BSES-SF, KPAS, EATS, and 
selected items from the DSQ.  The Breastfeeding Assessment is based on 44 questions.  
Cronbach’s alpha will be used to test the internal consistency of the data.  The “difference in 
Breastfeeding Assessment scores between recruitment and at study closure” across all three 
study arms will be assessed using the multiple linear regression approach.  The model will be 
adjusted for the effect of age, race/ethnicity, level of education, annual household income, family 
history of diabetes, pre-diabetes status, and parity.  The BSES-SF score is based on 14 questions 
and ranges from 14 to 70 points.  Cronbach’s alpha will be used to test the internal consistency 
of the data.  The “difference in BSES scores between recruitment and at study closure” across all 
three study arms will be assessed using the multiple linear regression approach.  The model will 
be adjusted for the effect of age, race/ethnicity, level of education, annual household income, 
family history of diabetes, pre-diabetes status, and parity.  The KPAS score comprises of 38 
questions that are distributed sequentially but non-uniformly across four sections and measure 
household and family care activities (household index); occupational activities (occupational 
index); active living habits (active living index); and participation in sports and exercise (sports 
and exercise index).  For each section, Cronbach’s alpha will be used to test the internal 
consistency of the data.  For each index of physical activity, “difference/change between 
recruitment and at study closure” across all three study arms will be assessed using the multiple 
linear regression approach after adjusting for the effect of the previously stated covariates.  The 
EATS survey consists of 10 questions, and up to 6 questions will be selected from the DSQ.  For 
each question, counts and percentages will be reported for participants at recruitment and at 
study closure across all three study arms.  
 
 
 
Section IV. Patient Protections and Methods to Minimize Risk 
 
A. Risks to Human Subjects 
a. Human Subjects Involvement, Characteristics, and Design 

 
 DPP Feasibility Study of Breastfeeding 
 
17 
 
The focus of this research is to implement and determine the feasibility and efficacy of an 
intervention that is based on the Diabetes Prevention Program (DPP) and includes intensive 
breastfeeding support and counseling in a cohort of overweight or obese pregnant women to be 
followed during pregnancy through 6 months postpartum.  Study participants will be pregnant 
women who reside in or near Wichita and in or near Lakin, Kansas.  Participants are eligible if 
they meet study inclusion criteria.  This is a randomized controlled pilot study with three study 
arms.  Participants will be randomized to each arm of the study by computer.  Participants in Tx1 
will receive the DPP plus breastfeeding, participants in Tx2 will receive the DPP only, and 
participants in Tx3 will receive usual care.  Usual care consists of (1) the same obstetrical care 
that pregnant women with normal body mass index (BMI) receive, and (2) obstetrical care that is 
provided to pregnant women by the same provider (Dr. Michael Wolfe).  Total enrollment for 
the proposed study will be 60 pregnant female participants.     
 
Participants are recruited from an obstetrical clinic at Via Christi Hospitals Wichita, Inc., a 
regional medical center located in Wichita, Kansas, and Kearny County Hospital, a critical 
access full-spectrum rural hospital, in Lakin, Kansas.  Participants must be women 18 years old 
or older, pregnant, with a BMI ≥ 25 and <35, and able to read and understand English.  Eligible 
participants will be recruited during the 1st trimester or early during the 2nd trimester.  General 
study exclusions include women who have pregnancy complications that require emergency 
care, have thyroid disease, have multiple gestation, had substance abuse within last 3 years, have 
an ART (Assisted Reproductive Technology) pregnancy, are a current smoker, had prior bariatric 
surgery, have been in a weight-loss program within 3 months of conception, have a BMI ≥ 35, 
are unable to attend intervention/follow-up visits, are unwilling to self-monitor data collection, 
are unable to complete the intervention, have a presence of any condition that limits walking, 
have a presence of any condition that limits following diet recommendations, or have a 
pregnancy complicated with a fetus diagnosed with lethal malformations/conditions. 
 
Vulnerable populations in this study might include economically/educationally disadvantaged 
persons.  Some pregnant women may be economically and/or educationally disadvantaged based 
on their demographic profile.  We especially want to accommodate these individuals as our 
study’s focus is on measuring postpartum weight, breastfeeding behaviors, HbA1c and blood 
pressure among an at-risk ethnically and racially diverse, overweight and obese pregnant 
population.    
 
We will obtain approval from the Institutional Review Board (IRB) at the University of Kansas 
School of Medicine-Wichita (KUSM-W), Via Christi Hospitals Wichita, Inc. (VCH), and 
Kearny County Hospital (KCH).  Via Christi Hospitals Wichita, Inc. and Kearny County 
Hospital are agreeable to allow Dr. Jacobson and her research team access to use their patient 
population to recruit study participants.  With the active assistance of Dr. Wolfe, maternal fetal 
medicine specialist at both hospitals, Dr. Jacobson and her research team will recruit each 
participant for the study.  All members of the research team involved in consenting and enrolling 
participants have successfully completed institutional Human Subjects training.   

 
 DPP Feasibility Study of Breastfeeding 
 
18 
 
 
b. Sources of materials 
Research material obtained from participants will include: socio-demographic data (i.e. age, 
race/ethnicity, income, education level, etc.), breastfeeding self-efficacy, physical activity level, 
dietary assessment, level of postpartum depression, weight, height, HbA1c, mean arterial blood 
pressure, blood glucose tolerance level during pregnancy, breastfeeding initiation, breastfeeding 
duration, use of formula, and solid food.  All data are based on validated questionnaires (except 
for the Breastfeeding Assessment questionnaire), and activity and nutrition monitoring as 
required by the DPP protocol.  The validated measures that will be used are the Breastfeeding 
Self-Efficacy Scale-Short Form (BSES-SF), the Kaiser Physical Activity Survey (KPAS), the 
Fruit and Vegetable Intake Screener (EATS), the Dietary Screener Questionnaire (NHANES 
2009-10), and the Edinburgh Postnatal Depression Scale (EDPS).  These validated survey 
instruments will be administered at baseline (=study entry) and at study closure (=6 months 
postpartum).  At delivery and through the 6 month postpartum period, we will also obtain the 
infant’s height and weight.  Further, at delivery, we will measure if the mother will start 
breastfeeding and we will measure how long she will continue breastfeeding through 6 months 
postpartum.                 
 
All behavioral assessments/surveys will be completed in a private room without the researcher 
present.  All DPP orientation sessions and breastfeeding classes will take place at Via Christi 
Health or Kearny County Hospital (depending on the residence of the study participant).  Data 
collected will be stored on a secure drive backed up on a nightly basis by the Information 
Technology (IT) department at KUSM-W.  Identification numbers will be assigned to each 
participant at the time of initial survey completion.  All hard-copy and data files will be labelled 
according to participant number.  Only the research team will have access to information 
regarding demographic and medical information and identification number for each participant.  
All other data collected throughout the duration of the study will be kept in locked cabinets and 
on a secure server within the University of Kansas School of Medicine-Wichita.  Data used for 
analysis will be de-identified and accessible only by the research team.  A log will be kept of all 
data collection and analysis steps completed for each participant. 
  
c. Potential risks 
Participants will undergo an intervention that is educational.  Participants will share education on 
exercise and diet, and will then apply these concepts in their daily functioning.  During the study, 
participants’ weight, HbA1c and mean arterial blood pressure will be measured.  During 
pregnancy, the breastfeeding component of the proposed intervention is highly visual and 
interactive.  An International Board Certified Lactation Consultant (IBCLC) will demonstrate 
proper breastfeeding techniques and strategies.  After delivery, participants will have access to 
an IBCLC up to 6 months postpartum.  There are no known risks of subjects participating in an 
educational intervention.  All data will be kept anonymous and in a locked file cabinet in a 
locked office.  All data will be entered into a computer; electronic data will be on a secure server 
at KUSM-W that is backed up on a nightly basis by the IT department at KUSM-W.        

 
 DPP Feasibility Study of Breastfeeding 
 
19 
 
 
A potential risk of participating in the study is a breach of confidentiality and loss of privacy.  
Privacy measures for participant responses to the questionnaires are described below.  Yet, to 
further address privacy, as well as to insure confidentiality, the investigators will ensure the 
following measures are taken.  All data obtained in the study will be kept confidential.  The only 
parties having access to the data in the proposed study will be the Principal Investigator (Dr. 
Jacobson), Dr. Jacobson’s research team, and the Institutional Review Board of record.  
Hardcopies of completed participant questionnaires will be locked in a secure file cabinet in the 
PI’s office.  Responses to the surveys and the clinical information obtained will be maintained on 
the KUSM-W REDCap database.  Only the necessary members of the research team will have 
access to the REDCap database.     
 
B. Adequacy of Protection Against Risks 
a. Recruitment and Informed Consent 
Participants will be recruited from the obstetrical clinic located at Via Christi Hospitals Wichita, 
Inc., a regional medical center located in Wichita, Kansas, and at Kearny County Hospital, a 
critical access full-spectrum rural hospital, in Lakin, Kansas.  We will use printed flyers, posters 
and word-of-mouth advertising to recruit potential participants.  Prior to using these recruitment 
materials, IRB at Via Christi Hospitals Wichita, Inc. will review and approve these materials.  
Dr. Michael Wolfe, Via Christi Hospitals Wichita, Inc. and Kearny County Hospital’s maternal 
fetal medicine specialist, will make the initial contact with a potential participant during her first 
prenatal visit and screen for inclusion criteria.  If Dr. Wolfe believes a potential participant meets 
inclusion criteria, then he will familiarize her with the nature and purpose of the study.  If the 
potential participant is interested in the study, then he will give her a study brochure and a hard 
paper copy of the consent form.  Prior to using this study brochure, the brochure will be 
reviewed and approved by the IRB at Via Christi Hospitals Wichita, Inc.   By providing the 
potential participant with a copy of the consent form, this will serve as the verbal consent script. 
 
Then, Dr. Wolfe will provide Dr. Jacobson and her research coordinator the potential 
participant’s contact information (i.e., participant name, email address, telephone number).  After 
receiving a potential participant’s name and phone number from Dr. Wolfe, the research 
coordinator will follow up with a phone call or meet with the interested participant in-person in 
an on-site, private conference room immediately after their prenatal appointment to determine if 
the potential participant again meets study inclusion criteria.  If she does, the coordinator will 
screen if the potential participant meets study exclusion criteria during the same phone call or 
during this same in-person on-site visit (see Table 1).  Before the research coordinator screens 
for inclusion and exclusion criteria, during this same phone call or during this same in-person on-
site visit, verbal consent will be obtained between the participant and the research coordinator, 
using the consent form as the verbal consent script, and then written e-consent will be obtained 
via REDCap at the orientation session.  When a participant is recruited on-site, then the in-
person visit between the participant and the research coordinator is considered to be the 
orientation session. 

 
 DPP Feasibility Study of Breastfeeding 
 
20 
 
 
If the participant meets all study criteria and the participant is contacted via telephone and not in-
person on-site, then the research coordinator will provide her with a time and place for the DPP’s 
orientation session and to complete study-related survey instruments.  The research coordinator 
will also verify the participant’s email address to provide her with informed consent materials for 
review.  Study procedures will be explained verbally by the PI and in writing at the time of 
survey completion and, again, at the DPP’s orientation session.  All subjects participating in the 
study will consent to participate as evidenced by signing an informed e-consent form via 
REDCap immediately prior to commencement of the orientation session.  Subjects will be 
informed that they are free to withdraw their consent at any time during the study with no 
penalty. 
 
Written informed e-consent will be obtained via REDCap from each participant prior to 
completing the first questionnaire.  A verbal explanation of the study will be provided in addition 
to the written explanation included in the consent form.  Potential participants will be 
encouraged to ask questions concerning the study.  After reading the consent form, participants 
will be asked to provide a verbal summary of the study as they understand it.  This will be used 
to assess the participant's understanding of the study.  If potential participants are able to 
understand, remember, and verbalize the main aspects of the study, it will be assumed that they 
have the capacity to consent.  Participants will be informed that they can withdraw from the 
study at any time by contacting research personnel.  When consent is withdrawn, participation in 
the study will be terminated and no additional data will be collected or used for analysis.  All 
patients will receive a copy of their signed consent form.  The original signed consent forms will 
be kept in a locked file cabinet in a secure data storage room in Dr. Jacobson’s office area, which 
can only be accessed with a key.  
 
b. Protection Against Risk 
All information we obtain throughout the study will be kept confidential.  The risks associated 
with the study are minimal.  No adverse events are anticipated with this study, but procedures 
will be in place to monitor the study using the scientific protocol provided and approved by the 
Institutional Review Board of record.  Participants experiencing any adverse effects from 
participating in this study will be directed to the PI.  Action will be taken to direct the study 
participant to the appropriate resources.   
 
Information collected throughout the course of the study will be de-identified of Protected Health 
Information (PHI), and will only be accessed by research staff directly involved with the study.  
Researchers believe there is less than minimal risk regarding economic risks and legal risks 
pertaining to this study. However, the risks associated with this project are considerably 
reasonable in comparison to the potential benefits from the study.  
 
c. Adverse Events 

 
 DPP Feasibility Study of Breastfeeding 
 
21 
 
In the case an adverse event were to occur due to study procedures, the principal investigator, Dr. 
Jacobson, will assume responsibility for reporting and documenting any complications.  All 
adverse events will be recorded and the necessary documents will be completed.  The principal 
investigator and/or the project coordinator will notify the IRB within the appropriate time frame. 
The investigators and project coordinator are responsible for complying with any reporting 
requirement of the reviewing IRB. 
 
If an adverse event should occur, the participant will have the opportunity to withdraw from the 
study.  Dr. Wolfe will be available for consultation should an adverse event happen.  Throughout 
the study, we will be monitoring for issues related to safety of participants as well as privacy of 
data.  Should an adverse event occur, the research team will document the event.  The following 
information will be monitored throughout the study: number of participants screened and 
enrolled, drop-outs, and serious and non-serious adverse events.  This data, with the exception of 
serious adverse events, will be reported every 12-months. Because no serious adverse events are 
anticipated in this study, any such events will be immediately reported to the Institutional 
Review Board of record.  If the severity of an adverse event requires emergency medical 
attention, appropriate providers/staff will be contacted to provide medical attention.  To assess 
participant safety even further, we will have a Data and Safety Officer in place.  Dr. Paige Geiger 
has agreed and is confirmed as the Data and Safety Officer for our study.  Paige Geiger, PhD, is 
a full professor in the Department of Molecular and Integrative Physiology, University of Kansas 
School of Medicine-Kansas City, Mailstop 3043, 3901 Rainbow Boulevard, Kansas City, KS  
66160.   
 
C. Potential Benefits of the Proposed Research to the Subjects and Others 
The potential benefit of this study is to determine if a combined breastfeeding, DPP-based 
intervention reduces postpartum weight, increases breastfeeding, and improves mean blood 
glucose (HbA1c) and mean arterial blood pressure, among an at-risk population with a BMI ≥ 
25.  This is an innovative way to address physical activity, weight, and breastfeeding in one 
intervention that is modeled after the evidence-based Diabetes Prevention Program and could be 
integrated into the continuum of healthcare services provided to culturally, diverse at-risk 
pregnant women.  Results of the proposed intervention will inform the development of 
interventions aimed at reducing diabetes risk factors and potential progression to type 2 diabetes 
after pregnancy among at-risk women.  The overall impact of this project will be to reduce 
diabetes risk factors among a high-risk population and inform interventions aimed at reducing 
these risk factors thereby decreasing disproportionate morbidity.  Moreover, study results will 
add significant knowledge to the field of diabetes prevention and related behavioral health 
interventions and strategies to improve maternal and child health outcomes.  Although the 
randomization process will not be performed by a clinician, instead it will be generated by a 
computer system, participants may still have concerns about bias (who receives the treatment 
versus who receives the control).  We will inform them that, regardless of group assignment, 
they will continue to receive routine care from their maternal fetal medicine specialist.      
 

 
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D. Importance of the Knowledge to be Gained 
Knowledge to be gained from this study is whether a combined breastfeeding, DPP-based 
intervention reduces diabetes risk factors among an at-risk population.  Results of this study will 
enhance current intervention efforts that aim to reduce diabetes risk factors and potential 
progression to diabetes during and after pregnancy and improve breastfeeding thereby improving 
maternal and child health outcomes.  An intervention that starts during pregnancy and extends 
beyond pregnancy has a high likelihood of success because during this time period, women are 
more inclined to change their behavior to benefit their children leading to reduced risk of 
retaining excess weight and a possible subsequent healthier pregnancy.  The knowledge, 
methodologies, and strategies obtained from this study will be of importance to the submission 
of a larger research grant such as an R01with the National Institute of Diabetes and Digestive 
and Kidney Diseases (NIDDK) that will involve a longitudinal study with a larger sample size of 
high-risk, ethnically and racially diverse Kansas women and their children to assess if a 
combined breastfeeding, DPP-based program reduces maternal risk for diabetes and impedes the 
cycle of obesity as a diabetes risk factor among families.  The R01 is a Research Project Grant 
and is the original and historically oldest grant mechanism used by the National Institutes of 
Health (NIH).  The R01 provides support for health-related research and development based on 
the mission of the NIH.  An R01 can be investigator-initiated or can be solicited via a Request for 
Applications by the NIH.  The R01 is an award made to support a discrete, specified, 
circumscribed project to be performed by the named investigators in an area representing the 
investigators’ specific interest and competencies, based on the mission of the NIH.  It is believed 
that the minimal risk involved in the proposed study is reasonable considering that it could lead 
to more effective ways to reduce diabetes risk factors among at-risk populations with a greater 
burden of disease and risk for related health complications.  The proposed pilot study will be the 
first to use an intensive breastfeeding, DPP-based program to reduce diabetes risk factors among 
a vulnerable, at-risk population. 
 
E. Privacy and Confidentiality 
This is an educational intervention utilizing identified pre- and post-surveys.  The privacy and 
confidentiality of potential participants will be maintained as all study data will be protected and 
only study personnel have access.  
 
Only the listed investigators and their designated staff will have access to the surveys and study 
data.  The University of Kansas School of Medicine-Wichita IRB, the US Department of Health 
and Human Services, the Office of Human Research Protections, and other government and 
regulatory bodies as required by law may have access to these research data.  Information 
technology protections and firewalls are in place at all study facilities, and will protect the 
electronic data stored at each facility.  Secure email will be used to transfer documents between 
investigators.  The database (participant identifiers removed) will be encrypted and password-
protected when sent through secure email between investigators. 
 
F. Waiver of Documentation of Consent  

 
 DPP Feasibility Study of Breastfeeding 
 
23 
 
A Waiver of Documentation of Consent is not requested for this study.  This study presents no 
more than minimal risk to study participants as the information obtained is not sensitive in 
nature, and if inadvertently released should not be injurious to the participants, either financially, 
legally, or personally.  Surveys will not ask for a participant’s name, medical record number, 
birthdate, social security number, or any other protected health information.  However, it is 
critical that the pre- and post-surveys, along with data on individual weight loss, HbA1c, mean 
arterial blood pressure and length of breastfeeding are linked to the same individual to assess 
health outcomes.  Therefore, research personnel will seek informed written consent and the 
process for obtaining written consent is outlined previously under Item B. Adequacy of 
Protection Against Risks, Item a. Recruitment and Informed Consent.     
 
G. Adherence to Study Protocol 
Protocol adherence is the primary responsibility of the principal investigator.  The co-
investigators will serve to support protocol adherence efforts and maintain an understanding of 
all protocol details.  Protocol amendments, revisions, deviations will be promptly reported to the 
IRB. 
 
H. Secure and Maintain IRB Approval at All Sites 
IRB approval will include all the study locations listed previously.  All protocol deviations, 
amendments, revisions, and continuing review reports will be promptly compiled and reviewed 
by the principal investigator and co-investigators, and provided to the IRB.  All research within 
the scope of this project will be conducted under IRB policies and guidelines. 
 
 I. Obtain IRB Approvals Prior to Implementing Changes to Protocol 
The principal investigator and co-investigators wish to assure the IRB that any amendments to 
the protocol or supporting documents will be submitted for approval prior to implementation; 
problems associated with the research will be reported in accordance with IRB policies. 
 
J. Modifications to Study Protocol and Oversight 
Each review will consider whether or not the study should continue without change, be modified, 
or be terminated.  Recommendations regarding modification of the design and conduct of the 
study might include: 
1. Modification of the study protocol based upon review of the safety data;  
2. Optional approaches when the incidence of primary study outcomes is substantially less 
than expected such as recommendations to extend study site;   
3. Corrective actions regarding the study site. 
4. To assess participant safety, we will have a Data and Safety Officer in place. 
 
The principal investigator and co-investigators will provide oversight, supervision and 
monitoring of the data collection and will insure integrity of the data which will ultimately 
ensure subject confidentiality.   
 

 
 DPP Feasibility Study of Breastfeeding 
 
24 
 
K. Monitoring Unanticipated Problems 
The principal investigator, Lisette Jacobson, will assume responsibility for: 
1. Data quality, completeness, and timeliness; 
2. Adherence to the protocol; 
3. Factors that might affect the study outcome or compromise the confidentiality of the trial 
data (such as protocol deviations). 
The principal investigator will consult with the research team/co-investigators regarding protocol 
revisions and amendments before adopting such changes. The IRB will be notified of any 
problems during the conduct of this study. 
 
L. Ensure General Coordination of Study Conduct 
The principal investigator agrees to accept responsibility for the scientific conduct of this study 
and for the rights and welfare of human subjects.  General oversight of the coordination of this 
study will be provided by the principal investigator. 
 
M. Record Retention 
All other study related documents (protocols, databases, IRB documents, surveys) will be 
retained for fifteen (15) years from the data of initial IRB approval and will be kept in the 
principal investigator’s office (University of Kansas School of Medicine - Wichita) under lock 
and key at the conclusion of this study.  At the time of document disposal, documents will be 
shredded according to KUMC Research Institute Record Retention guidelines.  The University 
of Kansas School of Medicine record retention policy requires research records involving human 
subjects to be kept for at least 15 years so all data associated with this study will be kept for at 
least 15 years.   
 
 
Section V. Results, Source of Funding, and Study Timeline 
 
A. Dissemination of Results 
The findings of this study will be submitted to peer reviewed public health and diabetes 
prevention journals (i.e. American Journal of Public Health, Diabetes, Diabetes Care, Diabetes 
Obesity and Metabolism, Health Education and Behavior, Maternal Child Health Journal, etc.), 
and may be presented at conferences (i.e. Society of Behavioral Medicine, American Public 
Health Association, American Diabetes Association, National Rural Health Association, research 
forums, ACOG, district meetings, obstetrical updates, etc.).  The IRB will be notified at time of 
continuing review of the research project.  Additionally, findings will be used in the future to 
obtain grant funding and for future intervention development. 
 
B. Source of Funding 
This study will be funded by the National Institute of Diabetes and Digestive and Kidney 
Diseases (NIDDK), grant number 1K01DK113048-01A1.  
 

 
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25 
 
C. Study Timeline (tentative) 
The following timeline is suggested for study completion. 
 
Suggested Timeframe 
Completed Objective/Goals 
September 2018 – December 2018 
IRB protocols, preliminary work including 
hiring of research coordinator, and working 
working with clinical staff at both hospital 
sites  
January 2019 – August 2019 
Finalize planning for participant 
recruitment 
September 2019 
Start recruitment (rolling recruitment over a 
9 month period) 
September 2019 – September 2021 
Intervention, data collection, preliminary 
data analysis 
September 2021 
Intervention/trial closes 
September 2021 – December 2022 
Final data analysis, manuscript completion, 
dissemination of findings, preparation for 
R01 submission 
January 2023 – September 2023 
R01 submission 
 
 
 
Section VI. Attachments/Appendices: 
 
1. Appendix 1 – Survey Instrument, Breastfeeding Self-Efficacy Scale-Short From (BSES-
SF) and Breastfeeding Knowledge Assessment (the Breastfeeding Knowledge assessment 
includes questions regarding socio-demographic data and health status data; these data 
will only be collected at study entry) 
2. Appendix 2 – Survey Instrument, Kaiser Physical Activity Survey (KPAS) 
3. Appendix 3 – Survey Instrument, Eating at America’s Table Study (EATS) Fruit and 
Vegetable Intake Screener 
4. Appendix 4 – Selected survey items (6) from the “Dietary Screener Questionnaire” 
(NHANES 2009-10) 
5. Appendix 5 – Survey Instrument, Edinburgh Postnatal Depression Scale (EPDS) 
6. Appendix 6 – Bristol Breastfeeding Assessment Tool (BBAT) 
7. Appendix 7 – Letter of Support from Via Christi 
8. Appendix 8 – Letter of Support from Kearny County Hospital  
9. Appendix 9 – Letter of Support from Dr. Michael Wolfe  
 

 
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26 
 
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