Backstrand JR, Goodman AH, Allen LH, Pelto GH. Pulque intake during pregnancy and lactation in rural Mexico: Alcohol and child growth from one to 57 months. Eur J Clin Nutr. 2004 Dec; 58 (12): 1,626-1,634.
PubMed ID: 15280906
To examine maternal intake of a mildly alcoholic beverage called pulque, during pregnancy and lactation, and its potential effect on postpartum child growth and attained size.
- Data on maternal diet during pregnancy and child anthropometry at one and 57 months was previously collected by the Mexico Collaborative Research Support Program in Human Nutrition (NCRSP)
- Infant births that occurred between October 1984 and November 1985
- The subjects were mother-infant pairs.
Exclusion criteria were not listed.
- This study was based on data collected by the Mexico NCRSP
- Recruitment was based on births that occurred in the project villages between October 1984 and November 1985.
A prospective cohort study.
- All statistical analyses were performed using SAS v. 8.2.
- Multiple regression was used to model attained size at 57 months and growth between one and 57 months
- The adequacy of the multiple regression models was assessed using residual plots and influence statistics
- All variance inflation factors for the regression analyses were well under three, which indicates that multi-collinearity was not excessive
- All correlations are Spearman's rank-order correlations. PROC LOESS, which employs a locally weighted regression technique, was used to illustrate the curvilinear relationships between pulque intake and child size and growth.
Timing of Measurements
- Maternal measurements were collected monthly and infant weights, lengths, skinfolds and circumferences were measured at birth, eight days and monthly thereafter, until eight months
- In the follow-up study, weights and heights of the children at a mean age of 57 months were obtained by a trained nurse at the Solis clinic.
- Variable 1: Infant attained size at 57 months
- Variable 2: Infant growth between one and 57 months.
- Maternal pulque and alcohol intake during pregnancy and lactation was estimated from dietary intake data for two consecutive 24-hour days monthly, during pregnancy and lactation
- Average number of records per participant was 9.5±4.8 days during pregnancy; 11.2±18 days during lactation.
- Initial N: 108 maternal-infant pairs
- Attrition (final N): 58 maternal-infant pairs
- Age: Infants were recruited at birth; the mean age of mothers was 30.4 years
- Ethnicity: Hispanic/Latino
- Other relevant demographics: Mean years of schooling of mothers was 2.3.
- Mothers' mean height was 152.5±5.5cm and
- Mothers' mean weight and BMI (30 days postpartum) was 57.1±7.9kg and 24.6±2.6kg/m2
- Location: Six villages in rural, central Mexico.
- During pregnancy, 69% of women reported alcohol consumption during pregnancy, all in the form of pulque
- Among the pulque drinkers (N=40), the median ethanol consumption was 125.1g per week and 30% of drinking mothers reported consuming more than 200g per week of ethanol
- The average ethanol intake per sitting was 23.5g, or slightly less than the alcohol content in two American beers
- During lactation, 72.4% of mothers reported pulque consumption. Pulque consumption during pregnancy and lactation were highly correlated (R=0.69, P<0.0001)
- The tallest and heaviest children tended to have mothers who consumed little or no pulque (50 to 300ml) during early lactation and small-to-moderate amounts of pulque intake during pregnancy. (Correlations between pulque intake during pregnancy with height for age was R=0.39, P=0.0131; weight for age, R=0.26, P=0.10; correlations between pulque intake during lactation with height for age, R=0.45, P=0.0025; weight for age, R=0.39, P=0.0111.)
- Child growth between one and 57 months showed little relation to maternal pulque intake during pregnancy. However, heavier maternal pulque intake during lactation was associated with slowest weight (P=0.0006) and linear growth (P=0.0002)
- The best predictors of larger child size and better growth were a lower proportion of days with heavy pulque intake, less pulque intake per drinking day and fewer drinking events per day.
Spearman's Correlations of Attained Size and Growth Measures with Maternal Intake of Pulque During Pregnancy (N=40) and Lactation (N=42)
|57 Months||57 Months||One to 57 Months||One to 57 Months|
|Height-for-Age||Weight-for-Age||Linear Growth||Weight Growth|
Percent of days that pulque was consumed
Preg: -0.41, P<0.01
Lact: -0.49, P<0.001
Preg: -0.32, P<0.05
Lact: -0.41, P<0.01
Lact: -0.42, P<0.01
Lact: -0.39, P<0.05
Percent of days with heavy drinking
Preg: -0.32, P<0.05
Lact: -0.41 P<0.01
Lact: -0.32, P<0.05
Lact: -0.40, P<0.01
Lact: -0.33, P<0.05
|Mean amount consumed per drinking day||
Lact: -0.37 P<0.05
Lact: -0.38, P<0.05
Lact: -0.35, P<0.05
Mean amount consumed per drinking event
|Mean number of drinking events per day||
Preg: -0.34, P<0.05
Lact: -0.45, P<0.005
Lact: -0.34, P<0.05
Lact: -0.32, P<0.05
Lact: -0.31, P<0.05
- Pulque is a nutrient-dense, mildly alcoholic beverage that is consumed in large quantities by many Mexican women
- This study reveals a curvilinear association between pulque intake during pregnancy and child height at 57 months, such that the tallest children were those whose pregnant mothers had consumed low to moderate quantities of pulque
- Due to the micronutrient content of pulque and its central role in a rural Mexican diet that is often lacking in a range of vitamins and minerals, it is suggested that low to moderate pulque intake may have fostered better fetal growth in this population
- Unfortunately, heavy ethanol intake during pregnancy can seriously damage normal fetal growth and development and have a long-lasting impact on child size. Heavier pulque intake during lactation was associated with smaller attained size at 57 months and slowed growth between one month and 57 months. This may be due to impaired breastfeeding performance.
- Strengths of this study include dietary assessment via multiple 24-hour recalls during both pregnancy and lactation, investigation of both attained size and postpartum growth and adjustment for a range of potential confounders. However, the study is observational in design and a range of alternative explanations might explain these associations. Also, the sample size is small and are not a perfect representation of the larger population
- Overall, the analyses show heavy maternal intake of pulque during pregnancy was associated with smaller child height and weight at 57 months of age. Heavier pulque intake during lactation was associated with poorer child growth between one and 57 months and smaller attained size at 57 months. Further research is needed to fully understand the risks associated with maternal intake of pulque.
Research Design and Implementation Criteria Checklist: Primary Research
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|1.1.||Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?|
|1.2.||Was (were) the outcome(s) [dependent variable(s)] clearly indicated?|
|1.3.||Were the target population and setting specified?|
|2.||Was the selection of study subjects/patients free from bias?|
|2.1.||Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study?|
|2.2.||Were criteria applied equally to all study groups?|
|2.3.||Were health, demographics, and other characteristics of subjects described?|
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|8.1.||Were statistical analyses adequately described and the results reported appropriately?|
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Copyright American Dietetic Association (ADA).