# Presentation: 557221

## Unintended pregnancy and its association with shorter breastfeeding duration: an assessment of Bolivia and Paraguay

**Carrie Shapiro-Mendoza, MPH, PhD****1**
**Beatrice J. Selwyn, ScD****1**
**David P. Smith, PhD****1**
**Maureen Sanderson, PhD****2**
**1 ****School of Public Health,**
**      ****University of Texas Health Science Center at Houston**
**2 ****School of Public Health, **
**      ****University of Texas Health Science Center at Brownsville**** **

##  We are guilty of many errors and faultsBut our worst crime is abandoning the children,Neglecting the fountain of life.Many things we need can wait.The child cannot.Right now is the time bones are being formed,Blood is being made, senses are being developed.To the child we cannot answer "Tomorrow."The child's name is "Today." -Gabriela Mistral, (1889-1957) 1945Nobel Laureate in Literature, Chile

## International health priority

**To decide when and how many children to bear **
**1995 Cairo Convention **
**basic human right**
**maternal health linked to child morbidity**
**Breastfeeding (BF)**
**exclusive BF for 1st six months**
**continued BF until 2+ years**** **

**Notes:**
Although having control over the number and timing of children to bear is widely accepted as a basic human right (1), as many as 50% of births in Latin America are identified as unwanted or mistimed at conception (2).   How this inability to control fertility affects maternal behavior (prenatal care, breastfeeding) and subsequent child health in developing countries is not well understood (3). 
There is substantial evidence that breastfeeding protects against , diarrhea,  chronic malnutrition, and respiratory infections (4-7).  Yet most children fail to meet the World Health Organization (WHO) recommendations for infant feeding: that is, exclusive breastfeeding for the first six months of life followed by the addition of nutritionally adequate and safe complementary foods along with continued breastfeeding up until two years of age and beyond (7-9).  
Although in developing countries the majority of children are initially breastfed, breastfeeding duration is significantly shorter in Latin America compared to Asia and Africa (10).  Additionally, breastfeeding practices vary among countries and cultures in these regions as well.  For example, Paraguay has one of the lowest one year breastfeeding continuation rates (61.3%), and Bolivia has one of the highest (85.1%) (10).  The percentage of children who exclusively breastfeed for at least six months is 5% in Paraguay, but 50% in Bolivia (11, 12).  In the past twenty years, breastfeeding duration rates have remained essentially stable in both countries (10). 

## Objectives

**To explore the association between pregnancy intention and breastfeeding duration**
**To compare associations among Bolivian and Paraguayan children**
**To differentiate between mistimed and unwanted pregnancies  **** **

**Notes:**
How a woman feels about her pregnancy at the time of conception may adversely affect maternal behavior such as breastfeeding initiation or duration.  If a mother feels negatively toward her child, this may interfere with infant bonding which in turn may affect the decision to breastfeed or length of time a mother chooses to breastfeed (23, 24).  Additionally, if an unwanted or mistimed pregnancy increased a mother’s stress level, in the subsequent birth it could reduce or suppress lactation (23, 25-28). 

The objective of this study was to explore the association of pregnancy intention and breastfeeding duration among Bolivian and Paraguayan children aged birth to 36 months old whose mothers report that their pregnancy was or was not intended at the time of conception, differentiating between mistimed and unwanted pregnancies.  
We chose Paraguay and Bolivia because both are developing countries in Latin America, but each has unique cultures, along with varying lengths of breastfeeding and unintended pregnancy rates. 

## Covariates available from the data 

**maternal age **
**maternal education**
**marital status**
**parity***** **
**rural versus urban residence **
**socioeconomic status**
**current pregnancy status **
**contraceptive use**

***effect measure modifier**

**Notes:**
Potential covariates available from the data included maternal age, maternal education, marital status, parity, rural versus urban residence, socioeconomic status, current pregnancy status, and contraceptive use (14-19).  Parity was explored as potential effect measure modifier because it was identified as such in a Ghanaian study.

## Methods

**Demographic and Health Survey (DHS)**
**Bolivia 1998**
**Paraguay 1990 **
**Cross-sectional survey**
**nationally representative sample**
**childbearing age women (15-49 years) **
**stratified,  2-stage multi-cluster sample design **
**Response rate – 93%**

**Notes:**
We analyzed data from the 1998 Bolivia  and the 1990 Paraguay Demographic and Health Surveys (DHS).  Both  surveys selected a nationally representative sample of women of childbearing age (15-49 years), using a stratified, two-stage multi-cluster sampling design.  Both surveys achieved an overall response rate of 93% (11, 12). 

## Data collection activities 

**Face-to-face household interviews **
**Mothers asked about:**
**reproductive history**
**child morbidity and mortality **
**breastfeeding status **
**fertility preferences **
**sociodemographic characteristics**

**Notes:**
Trained interviewers familiar with local languages and customs interviewed mothers at their homes using questionnaires.  Questionnaires were pretested, and incorporated local Spanish and indigenous dialects and vocabulary.  Mothers were asked about reproductive history, use of contraceptives, child health history, breastfeeding status, fertility preferences, and sociodemographic characteristics.  For the variables of interest in this analysis, both studies collected data using comparable questions.

## To measure pregnancy intention

**Mothers asked:**
**“****At the time you became pregnant with [name of last born child]**
**did you want to become pregnant then” - ****intended**
**“****did you want to wait until later” - ****mistimed**
**or did you want no more children at all” - ****unwanted**

**Notes:**
To measure pregnancy intention, the questionnaire asked respondents: 
“At the time you became pregnant with [name of last born child], did you want to become pregnant then, did you want to wait until later, or did you want no more children at all?”

The questions and definitions used here are standard for reproductive health surveys in the U.S. and abroad and are recognized in a 1995 Institute of Medicine review.

## Breastfeeding duration

**Maternal report **
**Number of months a child was breastfed**
**If child was still breastfeeding at the time of the interview**
**child’s age at that time recorded**
**censored observation**

**Notes:**
Breastfeeding duration was calculated as the number of months a child was breastfed according to maternal report.  For children still breastfeeding at the time of the interview, the child’s age at that time was used and it was noted that breastfeeding was continuing beyond the cutoff point. 

## Study population for analysis

**Children whose mothers report that their pregnancy was or was not intended at the time of conception. **
**Inclusion criteria for children:**
**Last born**
**Surviving**
**Singleton births**
**Born in the 36 months prior to interview **
**Sample size**
**Bolivia (n = 3445)**
**Paraguay (n = 1837)**

**Notes:**
Inclusion criteria for this analysis included children who were:  last born, surviving, singleton births, and born in the 36 months prior to interview whose mothers retrospectively reported their pregnancy intention at conception. 

The Bolivia sample was composed of 3445 mother/child pairs.
The Paraguay sample had 1837 mother/child pairs.

## Analysis of the data 

**Calculated incidence rates and hazards ratios**
**Survival analysis **
**Kaplan-Meier estimates and graphs **
**Cox proportional hazards (PH) regression**
**Tested PH assumption**
**Complex sampling design weights **

**Notes:**
We calculated incidence rates and hazards ratios for weaning among intended, mistimed, and unwanted pregnancies using survival analysis including kaplan Meier and Cox PH regression.  Hazards ratios for weaning were calculated using univariable proportional hazards (PH) regression analysis. To simultaneously adjust for confounders and to estimate more precise effect measure modification, we used multivariable PH regression.  
There was no evidence of violation of the proportional hazard (PH) assumption.  That is, the hazard ratios for selected exposures were consistent over the follow-up time.

To account for the complex sampling design and make appropriate estimates at the national level, we applied sample weights and adjusted for cluster effects using Stata statistical software (20).  For survival analysis and life tables, children still breastfeeding at the time of the interview were treated as censored observations. 

## Selected maternal sociodemographic characteristics of unwanted pregnancies in Paraguay and Bolivia.

**Older**
**Less educated**
**Multiparous**
**No flush toilet or latrine**
**Rural (Bolivia only)**
**Not currently using a modern contraceptive method (Bolivia only) **
**Currently working**

**Notes:**
In both countries, the characteristics of children from unwanted pregnancies differed from mistimed and intended pregnancies.  Children from unwanted pregnancies had older, less educated and multiparous mothers compared to children from mistimed or intended pregnancies.  These children more often lived in households without flush toilets or pit latrines.  Among children from unwanted pregnancies in Bolivia, more children resided in rural areas, but in Paraguay an equal number resided in urban and rural areas. 

## Intention status at conception of children in Paraguay and Bolivia in percentages

**Notes:**
This chart shows a comparison of intention status at conception of children in the Paraguay and Bolivia samples.  The prevalence of intended pregnancy was much higher in Paraguay compared to Bolivia,  74% versus  47%.  Of unintended pregnancies, mistimed was reported more often than unwanted in Paraguay, but in Bolivia the opposite occurred.  

## Bolivia

**Comparison of breastfeeding survival curves for last born surviving children, Bolivia DHS 1998 and Paraguay DHS 1990.**

**Bolivia**

**Paraguay**

**Notes:**
Nearly all children were breastfed at some time in both Paraguay (95%) and Bolivia (99%).  
Here we see the proportion of children continuing to breastfeed at given times from birth to 36 months of age.  At each point of duration, Paraguayan children had a lower probability of continuing to breastfeed relative to Bolivian children. 

## Proportion of children continuing to breastfeed up until 36 months by pregnancy intention status.

**Notes:**
Here we see Kaplan-Meier (KM) survival graphs that show the probability of continued breastfeeding up until 36 months by pregnancy intention status.  These KM curves were not statistically different in Paraguay, but they were for Bolivia.  Unwanted pregnancy was associated with later weaning for Bolivia and Paraguay.  

## Adjusted survival curves for breastfeeding duration derived from baseline hazards of multivariate Cox regression analysis, stratified by parity and pregnancy intention status for Bolivia DHS 1998.

**Adjusted survival curves for breastfeeding duration derived from baseline hazards of multivariate Cox regression analysis, stratified by parity and pregnancy intention status for Bolivia DHS 1998.**

***Adjusted for maternal education, region of residence, and current pregnancy status**

**Notes:**
This figure shows the association between pregnancy intention and breastfeeding duration modified by parity for Bolivia using the baseline hazards from the Cox multivariate regression.  Hazard ratios indicate relative risk of a mother stopping breastfeeding at any time adjusted for all other variables in the table. 
The survival curve for unwanted primiparae is consistently lower than other mistimed and intended pregnancies.  
Contraceptive use, place of delivery, mother’s age, and type of latrine were excluded from the model because they did not change the estimate of association or its 95% confidence interval by more than 10% when added to the model.
After adjustment for other significant factors, unwanted pregnancy in primipara was found to be significantly associated with breastfeeding duration. Women who had unwanted pregnancies and were priimipara at any time had a 1.25 times greater risk of having stopped breastfeeding at any time than women who were not primipara and had unwanted pregnancies at that time (adjusted hazard ratio [HR], 2.59, 95% confidence interval [CI] 1.54, 4.35). At any time in the first 3 years after the birth, primiparous women who had unwanted pregnancies had a 2.6 times greater risk of stopping breastfeeding than women who were not primiparas and did not have unwanted pregnancies. 
An unwanted pregnancy at the time of conception was associated with more than a two-fold risk of early weaning among children of primiparae (adjusted hazard ratio [HR], 2.59, 95% confidence interval [CI] 1.54, 4.35).  An unwanted pregnancy among multiparae, however, was associated with a longer duration of breastfeeding (HR, 0.84, 95% confidence interval 0.71, 1.00).  No statistical association was found for mistimed pregnancies regardless of parity.  

## Survival curves for breastfeeding duration derived from baseline hazards of multivariate Cox regression analysis, stratified by parity and pregnancy intention status for Paraguay DHS 1990.

**Survival curves for breastfeeding duration derived from baseline hazards of multivariate Cox regression analysis, stratified by parity and pregnancy intention status for Paraguay DHS 1990.**

***Adjusted for maternal education, region of residence, and current pregnancy status**

**Notes:**
This figure shows the association between pregnancy intention and breastfeeding duration modified by parity for Paraguay using the baseline hazards from the Cox multivariate regression.  
The survival curve for unwanted primiparae is higher than mistimed and intended pregnancies until about 13 months, and between 13 and 18 months falls below the other categories.  

For unintended and mistimed primps, it appears that they were less likely to wean early compared to intneded pregnancies, but the estimates here are very imprecise.  No association was found for multiparae and breastfeeding duration, regardless of pregnancy intention status. 

## Strengths

**Distinguished between mistimed and unwanted pregnancies**
**Used survival analysis**
**Measured BF duration vs never/ever**
**Measured risk**
**Compared different populations**

**Notes:**
The strengths of this study are as follows:
The current study differentiated unwanted and mistimed pregnancies. 
Many studies that have examined the association between pregnancy intention and child health have looked at unintended versus intended, but did not differentiate the unintended pregnancies by unwanted and mistimed.  Also, this is the first study in the literature to use survival analysis (time to event analysis) to study the association between pregnancy intention and breastfeeding duration.  Use of survival analysis allowed us to see when a specific event occurred, i.e., weaning versus just whether it occurred, i.e., ever/never breastfed as in logistic regression.

1.To estimate and interpret survival
characteristics:
2 Kaplan-Meier plots
2 Median estimation
2 Con ̄dence intervals (CI)
2.To compare survival in di®erent groups:
2 Log-rank test
3.To assess the relationship of explanatory
variables to survival time:
Cox regression model

In the United States, most studies have found an association between breastfeeding or intention to breastfeed and pregnancy intention (14, 29-36), but none examined breastfeeding duration beyond 4 months.

Additionally, this study compared 2 countries, both in Latin America, but with very different prevalences of pregnancy intentions and breastfeeding duration rates.  Although, the countries border one another, they have very different cultural practices and diverse ethnic populations.

## Limitations

**Retrospective report**
**Recall bias**
**Post-hoc rationalization**
**Validity & reliability unintended pregnancy questions**
**Selective survival bias**
**Other confounders**

**Notes:**
Like all study designs that rely on retrospective reporting, there is a potential for recall bias, especially for birth dates and reports of breastfeeding duration.  This analysis minimized recall error by asking mothers only to remember information on the last birth in the three years before the interview.  One way to determine the quality of retrospectively-collected data is to compare it to current status data (this will be shown in the next slide). As in other studies that measure pregnancy intention retrospectively, post-hoc rationalization is a concern because it creates misclassification.  For example, a mother may report that her now living child was intended at the time of conception even though in actuality the pregnancy had been unwanted or mistimed.  Most investigators agree that feelings or attitudes change from reports of  “unwanted” during pregnancy to “intended” following birth, thereby reducing the effect of any association (32, 43-47).  However, if a mother’s responses were based on the child’s health at birth, the effect on the association could be reduced or magnified (48).
Rewording the pregnancy intention question to have the mother refer to her feelings at conception helps minimize post-hoc rationalization (45).  Validity studies in Peru (49) and the Dominican Republic (45) found a reduction in post-hoc rationalization bias if pregnancy intention questions emphasized that the mother should respond based on her feelings at conception rather than during pregnancy or after birth.  This was done for the questions used for this analysis (45).

To avoid child mortality being a reason for weaning, only data on surviving children were analyzed.  In assessing the proportion of children who died by pregnancy intention status, the distributions were very similar.  For Bolivia, a slightly lower proportion of non-surviving children were classified as intended pregnancies (37%) compared to surviving children (47%).  In Paraguay, a slightly higher proportion of non-surviving children were classified as intended pregnancies (83%) compared to surviving children (74%).   

Children who die may also be at greater risk for shorter breastfeeding duration.

## Comparison of breastfeeding survival curves for last born surviving children, by current and retrospective maternal report, Bolivia DHS 1998 and Paraguay DHS 1990.

**Comparison of breastfeeding survival curves for last born surviving children, by current and retrospective maternal report, Bolivia DHS 1998 and Paraguay DHS 1990.**

**Notes:**
Another way to determine the quality of retrospectively-collected data is to compare it to current status data. 
This figure shows that for Paraguay and Bolivia, the curves for retrospectively reported and current status data are similar.  
Median durations are also similar for both types of reporting in both Paraguay and Bolivia.  
Differences between current and retrospective reports are greatest between 13 and 18 months for Paraguay and Bolivia, but differences rarely exceed 10%.  
Durations peak at 12, 18, and 24 months in the retrospective data for Bolivia and at 9, 12, and 24 months for Paraguay.  Peaks in the current status reported durations occur at 12, 17, and 23 months for Bolivia and at 9 and 22 months for Paraguay.  
The heaping is modest, suggesting that the data for retrospectively reported data for Paraguay and Bolivia are fairly accurate and not distorted by misreporting biases. 

In both countries retrospectively reported and current status median duration data are similar.  Differences between current and retrospective reports were greatest between 13 and 18 months for Paraguay and Bolivia, but differences rarely exceeded 10%.  The heaping was modest, suggesting that the data for retrospectively reported data for Paraguay and Bolivia were fairly accurate and not distorted by misreporting biases (18, 42). 

## Conclusions

**Primiparae with unwanted pregnancies have shorter breastfeeding durations in Bolivia, but not in Paraguay, taking into account child age, education, and socioeconomic status, and residence.**

**Notes:**
Breastfeeding initiation is universal in Paraguay and Bolivia, but compared to Bolivian children, Paraguayan children are weaned from the breast at earlier ages.  Overall, children of primiparae are weaned earlier compared to children of multiparae in Paraguay and Bolivia.  However, when this relationship is assessed by parity and pregnancy intention status, an association between pregnancy intention and breastfeeding duration is found for children from unwanted pregnancies from Bolivia only.  Thus, Bolivian children from primiparae who have unwanted pregnancies are at greater risk for earlier weaning than children from other pregnancies.  
Overall, those children with more educated mothers in Paraguay and Bolivia breastfeed for shorter durations than those with less educated mothers.  However, among mothers who had completed primary school, those from unwanted pregnancies breastfeed longer durations than those who were intended or mistimed.  To the contrary, no associations were found for breastfeeding duration and any of the pregnancy intention categories for those children whose mothers had not completed primary school. 
The results for Bolivia are consistent with a Ghanaian DHS study, in that a decreased duration of breastfeeding was associated with unintended pregnancies born to primiparae, although this study did not differentiate between mistimed and unwanted pregnancies.
Because of the different associations found, it is important for program planners and policy makers not to target subgroups of the population for breastfeeding interventions in the absence of country specific evidence regarding which groups should be targeted.  What needs to happen to meet the WHO recommendations for infant feeding is to develop programs that target the entire population, in effect attempting to change societal norms allowing everyone to benefit.  Finally, access to effective family planning to allow women to control their fertility is essential since lack of such ability may lead to adverse maternal behaviors and consequently to adverse child health.
Could it be that differences in levels of modernity and culture may account for the differing effects of pregnancy intention on breastfeeding duration?
Why might primiparae with unwanted pregnancies have shorter breastfeeding durations in Bolivia, but not in Paraguay, taking into account child age, education, and socioeconomic status, and residence?  This question deserves further examination.

## Comparison of maternal age

## Comparison of maternal education

## Comparison of maternal education

## Comparison of current contraceptive use

## Comparison of current modern contraceptive use by intention status

## Slide 28

## Slide 29

## Unintended Pregnancy and 

**Unintended Pregnancy and**** **

**Contraceptive**** ****use in Paraguay and **

**Bolivia**

**84**

**58**

**54**

**23**

**0**

**20**

**40**

**60**

**80**

**100**

**Bolivia,**

**1993–1994**

**Paraguay,**

**1990**

**Country and Year**

**Percent**

**% of births unplanned**

**If want no more births, % not using effective method**

**Notes:**
Source: DHS data from Paraguay 1990 and Bolivia 1993-94 (Alan Guttmacher Institute, 1997)

## Causes of unintended pregnancy

**Lack of access to effective contraception or abortion**
**Insufficient knowledge about family planning**
**Individual feelings, motivations, attitudes, and beliefs**
**Non-supportive sexual partners**
**Social forces **
**political or economic environments**
**religious authority**

## Causes of unintended pregnancy

**Failure to use contraception**
**Contraceptive failures**
**only accounted for 68% of the pregnancies that were reported as unintended.  **
**1995 NSFG, Trussell et al. 1999**

## Hazards ratios for breastfeeding termination, by pregnancy intention status, stratified by parity, Bolivia DHS, 1998.

**Primipara**

**Multipara**

**Hazards ratios for breastfeeding termination, by pregnancy intention status, stratified by parity, Bolivia DHS, 1998.**

***Adjusted for maternal education, urban versus rural residence, and current pregnancy status.**

## Hazards ratios for breastfeeding termination, by pregnancy intention status, stratified by parity, Paraguay DHS, 1990.

**Primipara**

**Multipara**

**Hazards ratios for breastfeeding termination, by pregnancy intention status, stratified by parity, Paraguay DHS, 1990.**

***Adjusted for maternal education, urban versus rural residence, and current pregnancy status.**