Subcutaneous fat accumulation during pregnancy in a malnourished population

Analysis and Reliability of Anthropometric Measurements during Pregnancy: A Prospective Cohort Study in 208 Pregnant Women

Anthropometric assessment during pregnancy is a widely used, low-technology procedure that has not been rigorously evaluated. Our objective is to investigate fat mass distribution during pregnancy by examining changes in anthropometrics measures, in order to evaluate the reliability of these measures. An observational, longitudinal, prospective cohort study was performed in 208 pregnant women. Anthropometric measurements were taken following the ISAK protocol during the three trimesters and a generalized linear model for repeated measures was used to evaluate differences. Variability was assessed using the coefficient of variation, and Propagated Error (PE) was used to sum of skinfold thicknesses (SFT). SFT showed a general increase in fat mass during the three trimesters of pregnancy (∑SFT7 p = 0.003), and was observed in specific anatomical locations as well: arms (∑Arm SFT, p = 0.046), trunk (∑Trunk SFT, p = 0.019), legs (∑Leg SFT, p = 0.001) and appendicular (∑Appendicular SFT, p = 0.001). Anthropometric measures for skinfold thickness were taken individually during pregnancy and were reliable and reproducible during the three trimesters, which could help to prevent adverse pregnancy outcomes.

Demographic and lifestyle factors associated with vitamin D status in pregnant Japanese women

Maternal vitamin D deficiency causes pregnancy complications and delayed skeletal development in offspring. This study aimed at identifying demographic and lifestyle factors associated with vitamin D status in pregnant Japanese women. A total of 284 healthy pregnant women in the second trimester were recruited at a university hospital in Tokyo, between June 2010 and July 2011. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were measured using chemiluminescent immunoassay. We assessed vitamin D intake using a self-administered diet history questionnaire and asked participants about lifestyle variables, including daily duration of sunlight exposure and supplement use. The mean (SD) serum 25(OH)D concentration was 9.8 (4.7) ng/mL. Almost 60% of the participants had severe vitamin D deficiency (measured as 25(OH)D<10 ng/mL). Multiple regression analysis showed that multigravidity, pre-pregnancy non-underweight status, higher energy-adjusted vitamin D intake, and use of vitamin D supplements were correlated with higher serum 25(OH)D concentrations (β=0.245, β=-0.119, β=0.226, and β=0.197, respectively). In the summer investigation, women with longer durations of sunlight exposure had significantly higher serum 25(OH)D concentrations (β=0.201) that were unrelated to the factors outlined previously. In the winter investigation, women with a high education level had higher serum 25(OH)D concentrations than others (β=0.330). Our results would be useful for identifying pregnant women at a high risk of low vitamin D status, such as primigravidae and those with pre-pregnancy underweight status, low education level, low vitamin D intake, and short durations of sunlight exposure.

Pregnancy-related changes in body fat

OBJECTIVE

To determine patterns of subcutaneous body fat change from preconception through 6 weeks postpartum, and factors that modify them.

STUDY DESIGN

A prospective study of 557 healthy women enrolled prior to pregnancy.

MAIN OUTCOME MEASURE

Body weight and skinfold thickness at the thigh, triceps, and subscapula, preconception, in each trimester, and 6 weeks postpartum, along with other variables.

RESULTS

Subcutaneous body fat stores remained stable (P>0.13) during the first 6 weeks after conception, and increased from 6 to 35 weeks by 1.5 mm at the triceps, 4.2 mm at the subscapular, and 7.3 mm (P<0.01) at the thigh areas. Body fat changes correlated poorly with weight changes, reflecting differences in the time course for the changes. They differed by preconceptional body mass index (BMI), parity, and infant gender (P<0.05). Women with the highest BMIs tended to gain less subcutaneous fat early, primiparous women gained more at thigh (P=0.01) and subscapular (P=0.027), and women carrying males had higher gains at the thigh (P=0.032) and subscapular sites (P=0.058) than other women. Breastfeeding status did not affect postpartum body fat changes, but women who breastfed exclusively had significantly lower skinfold thicknesses than non-exclusive breastfeeders from preconception through 6 weeks postpartum (P=0.041).

CONCLUSION

Subcutaneous body fat is stored and utilized at different sites at specific times during and after pregnancy. The pattern and amount of change varies depending on characteristics of women and their pregnancies.

Effect of fat and fat-free mass deposition during pregnancy on birth weight

OBJECTIVES

The purposes of our study were to describe the patterns and location of fat and fat-free mass deposition during pregnancy and to evaluate their effects on fetal growth.

STUDY DESIGN

Our study is a prospective follow-up of 105 healthy pregnant women who were delivered of term infants. Body composition was evaluated eight times during gestation with anthropometric measures and bioimpedance techniques. Body fat and fat-free mass were calculated with equations specifically developed for this population.

RESULTS

Total weight gain was 10.0 +/- 3.5 kg; net weight gain was 3.7 +/- 0.31 kg; birth weight was 3211 +/- 467 gm (values are mean +/- SEM). In these women fat was deposited mostly in the thigh and subscapular region for a total of 6.23 +/- 0.19 kg at term. The period of pregnancy of the largest maternal fat deposition per week is between the twentieth and thirtieth weeks. After adjusting by prepregnancy weight, birth weight is associated with maternal changes in thigh skin folds and fat gain before the thirtieth week of gestation. Infants born to mothers with low fat gain before the thirtieth week were 204 gm lighter than infants born to mothers with fat gain > or = 25th percentile of this population.

CONCLUSION

Maternal nutritional status at the beginning of gestation and the rate of fat gain early in pregnancy are the two nutritional indicators most strongly associated with fetal growth in this population.

Diet restriction by pregnant women in Nigeria

The reasons for food aversions given by selected low income, illiterate women during pregnancy fell into four categories: health, tradition, economy and religion. More than two thirds of these mothers strongly avoided milk, cowpea seeds and bournvita for fear of having big babies which they thought would lead to difficult labor and cesarean section. Only one of the respondents associated infantile rickets with nutrition. Nutritional counseling, coupled with a fear-mechanism technique for a minimum of four months, served to correct these erroneous assumptions. The effects of the counseling sessions were evaluated by monitoring patterns of maternal weight gain and the baby's weight. The experimental group had a significant pattern of monthly weight gain (P less than 0.02) and heavier babies (P less than 0.01) than the control group. The authors conclude that diet restrictions of this nature can be modified positively through regular nutritional counseling and, in extreme cases, by the use of a fear-mechanism technique.

Aging in selected anthropometric dimensions in a rural Zapotec-speaking community in the Valley of Oaxaca, Mexico

Stature, weight, arm circumference, triceps skinfold and grip strength were measured in a cross-sectional sample of 116 men and 113 women, 20-82 years of age, from a rural Zapotec-speaking community in the Valley of Oaxaca in southern Mexico. Mortality statistics, growth, and maturity status of children in the village are indicative of chronic mild-to-moderate under-nutrition. Adult Zapotecs are smaller, lighter and leaner than reference data for better-off populations. Sex differences are clearly evident for stature, fatness and grip strength. Body weight shows little sex difference after 40 years of age. Estimated mid-arm muscle circumference, however, is larger in males at all ages except over 60 years. Weight, arm circumference, the triceps skinfold and estimated muscle circumference are generally lowest in women 20-39 years, most likely reflecting the depletion of energy stores due to successive pregnancies and lactation. When stature is adjusted for the estimated loss associated with aging, there is suggestion of a secular increase in males but not in females. Sampling variation, small numbers at the older ages, and perhaps selective out migration must be considered in evaluating possible secular effects. Although absolute grip strength of adult Zapotecs is less than that of better-off samples of adults, grip strength per unit body weight is similar.