A Culturally-tailored Personalized Nutrition Intervention in South Asian Women at Risk of Gestational Diabetes Mellitus
Phase: NA
Conditions: Diabetes, Gestational
Sponsor: McMaster University

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Desi-GDM Trial Protocol Version 6.0 
 
A culturally-tailored personalizeD nutrition intErvention in South ASIan women at risk of 
Gestational Diabetes Mellitus (DESI-GDM) – a randomized trial  
 
Principal Investigator: 
Russell de Souza, ScD, RD 
 
Co-Investigators: 
Kristi Adamo, Sonia Anand, Harpreet Bajaj, Shrikant Bangdiwala, Hertzel Gerstein, Scott Lear, 
Sarah McDonald, Paul Ritvo, Diana Sherifali, Jennifer Stearns, Gita Wahi, Michael Zulyniak,  
 
 
Funded by: Canadian Institutes of Health Research (Project Grant) 
 
 
 
 

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Table of Contents 
 
1.0 
Introduction 
2.0 
Research Questions 
2.1 Primary Research Question 
2.2 Secondary Research Question 
3.0 
Research Design 
3.1 Randomization 
3.2 Blinding 
4.0 
Trial Population 
4.1 Inclusion Criteria 
4.2 Exclusion Criteria 
5.0 
Study Interventions 
5.1 Intervention Group  
5.2 Control Group 
6.0 
Study Measurements and Schedule 
7.0 
Study Outcomes 
8.0 
Safety Measurements 
8.1 Serious Adverse Events 
9.0 
Sample Size and Statistical Power 
10.0 Statistical Analysis 
11.0 Ethical Requirements 
12.0 Study Coordination and Management 
12.1 Data and Safety Monitoring 
 
References 
 
Table 1. Schedule of visit procedures 
 
 

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1.0 Introduction 
Gestational diabetes mellitus (GDM) is a condition in which a woman without existing diabetes 
develops high blood sugar levels during pregnancy1. Complications for the baby include neonatal 
hypoglycemia and intensive-care admission2, and GDM is a strong risk factor for future type 2 
diabetes (T2DM): up to 50% of women with GDM develop T2DM within 5 y of giving birth3,4, 
and face up to seven-fold higher lifetime risk of T2DM compared with women who have a non-
GDM pregnancy3,5. GDM is associated with future atherosclerosis and cardiovascular disease 
(CVD) in the mother and increases the risk of T2DM in offspring up to eight-fold.5-8 South Asians 
(SA), people whose ancestors are from India, Pakistan, Bangladesh, or Sri Lanka, are the largest 
non-white ethnic group in Canada, and are at high risk of T2DM and early CVD. SA women have 
at least double the risk of GDM of white European women, and risk factors for future T2DM in 
the offspring including higher birthweight, more adipose tissue, and reduced insulin sensitivity, 
are more common in SA infants of mothers with GDM than infants born to mothers without GDM.9 
 
Building upon our findings in START9, which identified diet as a key modifiable risk factor for 
GDM, and a qualitative study of barriers and facilitators to healthy eating encountered by pregnant 
and recently pregnant South Asian women and health care providers living and working in the Peel 
Region11, a region of Ontario where 20.9% of residents are South Asian10,12, we have developed a 
dietary intervention. Our conversations with women likely to benefit from this study and health 
care providers in the field have informed the development and delivery of our intervention.11 South 
Asian women voiced several facilitators to healthy eating such as: i) knowledge of culturally 
appropriate healthy foods, and ii) access to a health care provider able to provide resources and 
support in a timely fashion. They also identified barriers to healthy eating including: i) changing 
long-held cultural diet practices; ii) difficulty adapting standard dietary advice to personal health 
beliefs; iii) navigating food choices at family gatherings; and iv) accommodating meal needs of 
others in the household. The women we spoke with expressed a desire to learn more about healthy 
eating to prevent diabetes during pregnancy and were keen to use mobile health technology. Health 
care providers we spoke with identified two major challenges to providing appropriate advice to 
members of this community: i) insufficient time for counseling; and ii) lack of familiarity with 
South Asian foods. These findings are consistent with other studies of sociocultural influences on 
the behaviour of diabetic South Asian women in pregnancy12,13.  
 
A report from our partners at Peel Public Health12 emphasize that South Asian with diabetes living 
in Peel: i) report a lack of knowledge of “what to eat” that is healthy and culturally-appropriate, ii) 
face challenges accessing healthy foods, iii) have difficulty navigating social interactions that are 
food-focused, and iv) often lack control over food intake. Service providers, including family 
physicians, echoed these concerns and reported i) difficulty modifying the “unhealthy diet pattern, 
rich in fats, sweets, and carbohydrates”, with tools that are “Euro-centric” (Canada’s Food Guide), 
and ii) dietary guidelines that “can be confusing” to teach. Our dietary intervention will focus on: 
i) providing personalized food recommendations that consider a woman’s current dietary habits 
by identifying food choices and substitutions that will optimize the diet; ii) providing dietary 
advice that is sensitive to religious (e.g., vegetarian for Hindu, Buddhists, Jainists; inclusion of 
meat for Sikhs, Christians) and regional (e.g., Northern vs. Southern India, Sri Lanka, Bangladesh, 
Pakistan) culinary practices; iii) involving the household meal preparer, if this is not the participant 
herself, in the coaching contacts; and iv) use mobile health technology to reduce the amount of in-
office time a health care practitioner spends on dietary counseling. 

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1.1 Results of Pilot Study 
We have conducted a pilot trial of 20 pregnant South Asian pregnant women living in Peel Region 
to understand the feasibility of our proposed intervention. The results of the pilot study have 
informed the design and operations plan of the DESI-GDM trial. 
 
Recruitment: Between March 1 and July 31, 2019, one research coordinator working 2 days/week 
screened 30 women, enrolling 20 participants. All participants completed the study (retention = 
100%). Based on these early data, with our proposed full staffing, we will be able to screen 15 
participants per month, and randomize 10, reaching the desired 190 participants in 1.5 years, as 
projected.   
 
Feasibility and Adherence: We randomized 11 participants to the intervention, and 9 to control. 
Control group participants received a median of 8 (1 per week), and intervention group participants 
received a median of 10 text messages (1 per week) to encourage walking. Intervention participants 
received a median of 20 text messages (2 per week) tailored to her nutrition goals. Intervention 
participants received a median of 5 coaching calls (1 every 2 weeks), each lasting approximately 
10-15 minutes. Participants typically set 2-3 initial goals, modifying at least 2 goals during the 
intervention. Over 60% of participants met >80% of their goals.  
 
Acceptability: Nine participants agreed to participate in a short interview about their study 
experience, following completion of their OGTT visit. All 9 (100%) found the study useful, would 
recommend participation in this study to a friend, and would participate in future studies with our 
group. Reasons participants gave for participating in the study included a desire to receive health 
advice, and a desire to help the South Asian community. Knowing that someone was reviewing 
their data and supporting them helped them stay motivated, and the regular feedback from the 
health coach or text messages helped them stay on track with their goals. Women found the visit 
location convenient, and the staff communicative and respectful of their time. Of the 9 participants, 
7 felt the style and frequency of messages was acceptable, and 7 felt the frequency of health coach 
contact was adequate. Two control participants desired more messages and two participants wished 
for more frequent contact with the coach. Therefore, we have demonstrated that we can recruit and 
retain participants, and that the intervention is feasible to deliver and acceptable to participants. 
 
 
2.0 Research Questions 
 
This trial will assess the impact of a culturally tailored, personalized nutrition intervention on 
glycemic response to an oral glucose load (as measured by the area-under-the curve glucose) in 
high-risk pregnancies of South Asian women.  The intervention targets two at-risk individuals: 
mother and infant, “breaking the cycle” of maternal gestational dysglycemia, excess infant 
adiposity and insulin resistance, and CVD in both mother and baby. The findings of this study 
will be important in guiding future evidence-based recommendations and public health policies 
to manage gestational glycemia in pregnant women at risk of GDM. 
 
2.1 Primary Research Question 

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In pregnant South Asian women living in Peel Region, Ontario, does a culturally tailored, 
personalized nutrition intervention delivered by a trained health coach improve blood sugar 
levels in South Asian women to a greater extent than usual dietary advice? 
 
2.2 Secondary Research Question 
In pregnant South Asian women living in the Peel Region, Ontario, does a culturally tailored, 
personalized nutrition intervention delivered by a trained health coach to pregnant South Asian 
women reduces the incidence of gestational diabetes mellitus to a greater extent than usual 
dietary advice? 
 
3.0 Research Design 
 
3.1 Randomization 
Women will be randomized 1:1 to intervention or control using a centralized integrated web 
response system (IWRS) at the Population Health Research Institute (PHRI) in Hamilton. A 
statistician will generate a randomization list using a permuted blocks algorithm with randomly 
chosen block sizes to ensure balance in numbers and avoid predictability.15 At the baseline visit, 
the research assistant/health coach will confirm eligibility and obtain consent, either in person, 
verbally via telephone or web conferencing, or electronically via REDCap. After collecting 
baseline physical measures, the study personnel completing the visit will activate the IWRS to 
randomly allocate participants to control or intervention in a concealed fashion using a 
computer-generated random sequence. 
 
3.2 Blinding 
Randomization allocations will be determined by a statistician at the Population Health Research 
Institute (PHRI, Hamilton, ON) not involved in participant recruitment, assessment or study 
intervention, to ensure participant allocation concealment. In this complex intervention, one arm 
of the study will receive an intensive behavioural intervention, and the other arm will receive 
usual care. Therefore, the participants will not be blinded to treatment assignment. For 
administrative and logistical reasons, the staff revealing the randomization to the health coach 
will not be blinded. Because the health coach will be delivering the intervention s/he will also be 
aware of treatment assignment. Blinding will occur at outcome assessment (75 g, 2h OGTT). 
The staff who administer the OGTT will be unaware of treatment assignment, and they will 
assess the primary clinical endpoint (area-under-the curve of glucose [AUC] by 75-g oral 
glucose tolerance test [OGTT]). Data analysts will have no contact with study participants and 
will be unaware of treatment assignment.  
 
4.0 Trial Population 
 
4.1 Inclusion Criteria 
a) pregnant women;  
b) South Asian ancestry;  
c) gestational weeks 12-18;  
d) singleton pregnancy; and  

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e) ≥2 of the following GDM risk factors: age>29, low diet quality (assessed with a short diet 
screener17), family history of DM, GDM during a previous pregnancy, or a pre-pregnancy BMI 
≥23.17 
 
4.2 Exclusion Criteria 
a) type 1 or type 2 diabetes;  
b) high blood pressure (≥140 mmgHg systolic or ≥90 mmHg diastolic);  
c) poor understanding of English (93% of Canadian South Asian women in the National 
Household Survey could conduct a conversation in one or both official languages10);  
d) unwilling to modify diet, based on a screening question;  
e) at high risk of adverse pregnancy outcomes other than GDM (e.g., twins or higher-order 
multiples, use of fertility treatment, preexisting hypertension, history of placenta previa or pre-
term delivery);  
f) enrolment in another study; 
g) does not have a smartphone;  
h) not willing to walk; or 
i) excessive nausea and/or vomitting 
 
5.0 Study Interventions 
5.1 Intervention Group 
A personalized nutrition plan will be developed for each woman by a culturally congruent 
dietitian (de Souza). This plan will respect faith-based food choices (e.g., vegetarian for Hindu, 
Buddhists, Jainists; inclusion of meat for Sikhs, Christians), and regional preferences (e.g., North 
Indian diet: vegetarian, rich in yogurt, cream, starch from naan, chapatti, roti, and sweets vs. 
South Indian diet: non-vegetarian, rich in coconut curries, ghee, and starch from rice). The plan 
will be delivered by a culturally congruent health coach, and consider baseline dietary intake, 
energy balance for recommended gestational weight gain, personal values and preferences, 
through setting 2-4 “SMART” goals. Participants assigned to the intervention group will receive 
text messages that support 11 categories of nutrition goals, targeted to address eating behaviours 
identified by participants in our qualitative study, designed to optimize energy balance for weight 
gain, and improve dietary quality. Participants assigned to the intervention group will be given a 
Fitbit to track their steps. 
 
5.2 Both Groups 
Participants in both groups receive simple text messages weekly, aimed at increasing walking. 
Both groups will be given PDF resources that provide advice on healthy eating, physical activity, 
and other lifestyle factors during pregnancy plus additional materials adapted specifically for the 
South Asian community. Health care providers in Peel Region use these tools routinely (Diabetes 
Canada: https://bit.ly/2m8r2tT; or Heart & Stroke: https://bit.ly/2lDubl7). 
 
6.0 Study Measurements and Schedule 
Treatment duration will be between 6 and 16 weeks, depending on time of enrolment. In-person 
or Zoom study visit contact will occur 2 times: once for the baseline visit and once for the 
OGTT. Duration of follow-up ranges from 6 to 16 weeks, depending on gestational week of 
enrollment and OGTT timing. Between these visits, all participants receive weekly text 

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messages, and intervention participants will also have bi-weekly telephone or video conferencing 
(Zoom/Skype/Facetime).  
 
At the baseline visit, a member of the study team will screen eligible participants. After an 
informed consent discussion, study personnel will complete the baseline visit, which includes 
physical measures (height, weight, blood pressure, skinfold thickness and mid upper arm 
circumference), finger stick for glucose, fasting urine sample collection, fasting blood sample 
collection, questionnaires to assess sociodemographic characteristics, medical, obstetric and 
lifestyle histories, an Ayurvedic assessment, COVID-19 and vaccine questionnaires, and 
INTEHEART food frequency questionnaire. COVID-19 and vaccine questionnaires will be 
completed to provide context to the sociodemographic characteristics, medical, obstetric and 
lifestyle histories of participants. The COVID-19 pandemic has impacted all aspects of day-to-
day life, and these questionnaires will be available for analysis if needed to provide context to 
our findings. Health card numbers will be recorded for future linkage with administrative data 
sources from Ontario such as the Institute for Clinical Evaluative Sciences (ICES) for health 
economic evaluation and potential for long-term follow-up of mother and her child. 
 
Study personnel meet with all participants, and reviews their usual diet. Once baseline measures 
are collected, randomization takes place as described (section 3.1). Following group allocation, 
intervention participants develop a personalized nutrition plan with the health coach and will be 
provided training on how to use the Bitesnap application for food recording. Both intervention or 
control participants receive PDF or paper-based resources and web links to standard resources. 
The baseline visit will be approximately 1 hour. 
 
At the second clinic visit (24-28 weeks’ gestation), baseline physical measures, INTERHEART 
food frequency questionnaire, fasting urine sample collection and fasting blood sample collection 
are repeated and the 75-g OGTT is performed. Optional additional blood samples may be 
collected at multiple time points during the OGTT for future analysis if funding is obtained. Any 
future analysis will be relevant to DESI-GDM and will be submitted in a separate HiREB 
submission. 
 
Participants in both control and intervention groups receive at least 1 text message every week, 
sent by automated outbound messaging system, MemoTEXT.  
 
The intervention group only will be sent weekly text messages to reinforce individual nutrition 
goals. The intervention group will receive at least 2 text messages/week at times of day 
requested by the participant: one or more tailored diet text messages, and a message that provides 
1 of the 6 walking tips. Participants assigned to the intervention group will be given a Fitbit to 
track their steps and will track food in Bitesnap, a photo food journal app that integrates with the 
MemoTEXT dashboard, for 2 weekdays and 1 weekend day bi-weekly (up to 8 assessments). 
Health coaches will be able to view activity from the participants Fitbit via the Health Coaching 
Platform. Coaching calls to the intervention group will be made post-baseline weeks 2, 4, 6, 8, 
10, 12, 14, and 16 (bi-weekly up to OGTT). These coaching calls will be recorded using an audio 
recording device. At each scheduled contact, intervention participants review agreed-upon diet 
goals, and assess, on a Likert scale, how often they were able to meet them (ranging from 
“never” through “all of the time”); the coach works with the participant to overcome barriers 

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using our Brief Action Planning Guide. After each coaching call, participants and Health 
Coaches will complete a Visit Reflection questionnaire.  
 
The control group will receive 1 text message weekly up to OGTT with 1 of the 6 walking tips 
reviewed at baseline. The central coordinator will review data regularly for completion, and ad 
hoc calls may be made to clarify items, but no counseling is provided to control group 
participants. 
 
At the completion of their OGTT, each woman will be asked to complete the DESI-GDM exit 
survey (see attached). This is a 9-item questionnaire based on previous tools created and used by 
our group. Responses to each question are provided using a 5-item Likert scale (Strongly 
Disagree through Strongly Agree).  
 
Study participants will be contacted after delivering their baby to self-report the birth weight and 
length of their baby. Participants will also be asked to provide details of any complications 
during delivery.  
 
7.0 Study Outcomes 
The primary clinical outcome of this trial is the glucose area under the curve (glucose AUC). A 
measure of glycemic response, glucose AUC is a continuous measure of the response to a 75-g 
OGTT that accounts for variations in fasting plasma glucose levels between individuals. It is 
calculated by the trapezoidal method using the fasting, 1-h, and 2-h glucose10. The AUC is 
superior to a single measure, which, though convenient for diagnosis and treatment, may not 
provide complete information regarding the processing of plasma glucose after a load11.  
 
The secondary outcome is GDM, classified using the cut-offs derived in the BiB cohort: fasting 
glucose  5.2 mmol/L, or 2-hour post-load 7.2 mmol/L12. These cut-offs were associated with 
infant birth weight >90th percentile for gestational age and adiposity (sum of skinfold 
measurements [SSF] >90th percentile for gestational age) in this cohort12. Current clinical cutoffs 
for the 75-g OGTT used to diagnose GDM in the general population are: fasting glucose  5.3 
mmol/L, 1-hour   10.6 mmol/L, or 2-hour 9.0 mmol/L13. In Peel, pregnant women usually 
undergo a 50-g glucose challenge at 24-28 weeks, with a 1-h value ≥7.8 mmol/L being an 
indication for a 75-g OGTT14. We have selected the 75-g OGTT because: 1) it was used to 
establish South Asian-specific diagnostic criteria for GDM, and thus our outcomes will be 
directly comparable12, 2) it avoids the high false negative rate of the 50-g GCT among South 
Asians15,16, 3) one-step screening has potential for long-term cost savings17-19 , and 4) Diabetes 
Canada recognizes that the one-step strategy can identify a subset of women who would not 
otherwise be identified as having GDM and who may benefit with regards to certain perinatal 
outcomes.13 We will co-ordinate with the health care provider (section 2.13) to ensure 
participants receive the 75-g OGTT between 24-28 weeks, avoiding the two-step screen. A study 
endocrinologist (Bajaj) will review the OGTT results and send a letter to the participant’s 
provider communicating the result, to ensure continuity of care and appropriate management.  
We will assess the sensitivity and specificity of the BiB definition against the IASPSG or WHO 
criteria.  
 

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To evaluate safety outcomes, we measure maternal blood pressure at baseline and the OGTT 
visit, and note any pregnancy complications at coaching contacts. We will conduct comparisons 
of primary and secondary outcome data at the end of the trial, unless advised otherwise by our 
data safety monitoring committee (DSMC). 
 
8.0 Safety Measurements 
To evaluate safety outcomes, maternal blood pressure is measured at baseline and the OGTT 
visit, any pregnancy complications are noted at coaching contacts. Potential adverse events that 
may be experienced by the woman include induced labour, anemia, urinary tract infection, fall, 
low mood, or high blood pressure (minor); and miscarriage, pre-eclampsia, Cesarean section 
delivery, Hyperemesis gravidarum, post-partum hemorrhage (>500 ml). Potential adverse events 
for the baby include pre-term delivery (<36 w) or shoulder dystocia; and mortality or stillbirth 
(major).  
 
 
8.1 Serious Adverse Events 
Any untoward medical occurrence that: results in death, is life-threatening, requires inpatient 
hospitalisation or prolongation of existing hospitalisation, results in persistent or significant 
disability/incapacity, or is a congenital anomaly/birth defect will be reported to the Coordinating 
Centre within 1 business day of its discovery. A narrative summary will be prepared. 
 
9.0 Sample Size and Statistical Power 
With 95 participants per group, and an expected 10% loss-to-follow-up, we will have ≈86 
participants per group, which will provide 90% power to detect at least a 15% between group 
differences in AUC glucose, assuming 70% adherence to the intervention (i.e. goal setting, 
health coach contacts, tracking) and SD of AUC glucose = 173 mmol/min17. A change of at 
least this magnitude has been observed in trials of fibre supplements20 high-protein21 or high fat 
diets22. We will have 80% power to detect a 61% relative risk reduction in GDM. An effect of 
this magnitude is unlikely, so we will look to see if GDM is lower in the intervention. Failure to 
observe substantial impact on AUC glucose (i.e., <10% reduction) with no signal of benefit for 
GDM (i.e., an OR between 0.9 and 1.1), or a signal of harm (OR > 1.1) with high intervention 
fidelity will suggest that a larger trial primarily powered to detect differences in GDM is not 
warranted. 
 
10.0 Statistical Analysis 
 
We will assess the main effect of the diet intervention (β1) on the primary outcome of AUC 
glucose with a linear regression model with intervention as the main effect (a dummy variable, 
where 1=treatment; 0=control) 
a) Primary clinical outcome: We will assess the main effect of the diet intervention (β1) 
on the primary outcome of glucose AUC with a linear regression model with 
intervention as the main effect (a dummy variable, where 1=treatment; 0=control): 
[𝑔𝑙𝑢𝑐𝑜𝑠𝑒 𝐴𝑈𝐶
̂
] = 𝛽0 + 𝜷𝟏 𝒊𝒏𝒕𝒆𝒓𝒗𝒆𝒏𝒕𝒊𝒐𝒏+ 𝜀 

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b) Secondary clinical outcome: We will assess the main effect of the diet intervention (β1) 
on the secondary outcome of GDM by fitting a logistic regression model with 
intervention as the main effect (a dummy variable, where 1=treatment; 0=control):  
𝑙𝑜𝑔𝑖𝑡 (𝑃𝑟|𝐺𝐷𝑀= 1) = 𝛽0 + 𝜷𝟏𝒊𝒏𝒕𝒆𝒓𝒗𝒆𝒏𝒕𝒊𝒐𝒏+  𝜀 
c) Process and acceptability assessments: These data will be presented descriptively, and 
include monthly process feedback (e.g. recruitment, retention, adherence), which the 
team discusses on an ongoing basis (e.g. poor adherence, unmet goals). The study team 
review qualitative and quantitative data to refine processes and calibrate expectations. 
Acceptability will include a 9-item, Likert scale survey, administered after the OGTT 
visit (Supplementary Information “C”), which allow each participant a voice in the 
research experience, and convey what they liked and disliked about the study, and if 
they would recommend the program to a friend, as we have in 3 previous studies of 
similar design20-22.  
 
11.0 Ethical Requirements 
Participants will provide written, verbal or electronic informed consent. If providing verbal 
consent, participants will be sent the full consent via email or paper mail, to read and refer to 
while being consented. If providing electronic consent via REDCap, participants will be sent a 
link that contains the full consent and will review the consent over telephone or web-
conferencing with study staff. The participant will select whether they agree to participate at the 
bottom of the consent page. Participant data will be deidentified to protect confidentiality, and 
will only be reported and published in aggregate. 
 
12.0 Study Coordination and Management 
Dr. Russell de Souza will take responsibility for the oversight of the study. The coordinating 
centre for the trial will be Population Health Research Institute (PHRI) in Hamilton, ON. The 
coordinating centre, under the direction of Dr. Shrikant Bangdiwala in collaboration with Ted 
Scott, will receive all data, and take process steps to reduce missing data. Senior project 
manager, Ms. Dipika Desai, along with a student (TBD) who will oversee logistics of 
recruitment of participants, will handle central trial coordination. At weekly meetings, we will 
review recruitment, minor adverse events, study inventories, and review any expressed concerns 
by participants or the team.  
 
12.1 Data and Safety Monitoring 
The steering committee will direct operational/process (de Souza, Anand, Gerstein), nutrition (de 
Souza), coaching (Sherifali), and statistical (Bangdiwala) aspects of the trial. For our previous 
pilot study, we had convened a DSMC, consisting of an experienced endocrinologist, 
biostatistician, and internal medicine specialist. Our committee advised that a DSMC was not 
required for the pilot, voting for a safety officer, and disbanded 
 
During our pilot study, we convened a meeting with senior investigators (3 of which are also 
involved in this study- Anand, Bangdiwala, and Gerstein) on May 2, 2019. At this meeting, the 
senior members of the investigative team advised that a DSMB was not necessary for this trial. 
They instead advised that a safety officer be appointed to review data monthly (or more 

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frequently as indicated). Dr. Sonia Anand was appointed as the safety officer. She will retain this 
role for the study under submission herein. At each monthly meeting, she will review data, 
noting any of the 5 minor (premature labour, anemia, urinary tract infection, fall/injury/accident 
related to study, or high blood pressure), or 3 major maternal events (miscarriage, pre-eclampsia, 
or hyperemesis gravidarum); or 2 minor (pre-term delivery <36 weeks, or shoulder dystocia) or 2 
major (mortality or stillbirth) infant events. She will determine whether they are related to study 
participation. 
 
An interim data analysis, comparing 1) mean AUC glucose; and 2) GDM incidence between 
treatment and control (blinded) after the first 25 participants have completed their OGTT visit. 
Thereafter, we will have the committee review the data following each additional 50 participants. 
There is no early stopping rule for this study. We will only collect data at baseline and the OGTT 
visit. 
 
Table 1. Schedule of visit procedures 
 
Baseline 
Weekly  
Health 
Coach 
Visits 
OGTT 
Visit 
Post-
Birth 
Visit 
Screening 
x 
 
 
 
 
Informed Consent 
x 
 
 
 
 
Randomization 
x 
 
 
 
 
Physical Measures (height, weight, blood 
pressure, skinfold thickness, mid upper 
arm circumference) 
x 
 
 
x 
 
INTERHEART Food Frequency 
Questionnaire  
x 
 
 
x 
 
COVID-19 and Vaccine Questionnaires 
x 
 
 
 
 
Finger Stick for Glucose 
x 
 
 
 
 
75-g OGTT 
 
 
 
x 
 
Urine Sample Collection 
x 
 
 
x 
 
Blood Sample Collection 
x 
 
 
x 
 
Sociodemographic Questionnaire 
x 
 
 
 
 
Medical History Questionnaire 
x 
 
 
 
 
Obstetrics Questionnaire 
x 
 
 
 
 
Lifestyle Questionnaire 
x 
 
 
 
 
Ayurvedic Assessment 
x 
 
 
 
 
Device Identification* 
x 
 
 
 
 
FitBit Distribution* 
x 
 
 
 
 
Bitesnap Downloaded* 
x 
 
 
 
 
Resource Handouts 
x 
 
 
 
 
Walking tips via MemoTEXT  
 
x 
 
 
 
Diet reinforcement via MemoTEXT* 
 
x 
 
 
 

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* Intervention group only 
Calls With Health Coach (set and review 
SMART goals, Brief Action Planning 
Guide) * 
 
 
x 
 
 
Visit Reflection* 
 
 
x 
 
 
Bitesnap Food Journal* 
 
x 
 
 
 
FitBit Return* 
 
 
 
x 
 
Exit Questionnaire  
 
 
 
x 
 
Mother-reported Infant Physical 
Measures 
 
 
 
 
x 

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