Maternal nutritional determining factors in twin pregnancies

Abstract

Background Nutritional recommendations and weight gain patterns associated with optimal outcomes for singleton pregnancy (SP) are well documented but this information is deficient for multiple pregnancy (MP). Objective To identify the maternal nutritional determining factors in women with MP that gave birth products with an adequate birth weight. Method A case control nested in a cohort study was performed. Healthy pregnant women were evaluated monthly, since wk 20 until birth. Height, weight, skinfolds, uterine fundus height, and REE (by indirect calorimetry) were measured at baseline and during the following visits. Cases were women with MP that delivered products > 2100 g and controls were SP women that gave birth a product > 2900 g. GLM repeated measures were used for analyzing changes in all response variables throughout pregnancy (intra subjects comparisons) and between either MP vs SP or pregestational BMI (pBMI): < 25 and > 25. The protocol was approved by the INPer’s Research and Ethics Committees and women gave a written, informed consent. Results 19 MP and 20 SP women were followed with no significant differences between groups. 10 MP were defined as cases and 11 SP as controls. When analyzed by pBMI, women with BMI > 25 gained less weight than those with pBMI < 25 (Inter=F (1,19) 5.8 ; p=0.026, Intra =F(2, 38) 3.9; p=0.028). REE was no different between groups (p>0.05). SP women gained more body fat than those with MP (p>0.05). Conclusions The maternal nutritional determining factors in twin pregnancy depend on pBMI and not on pregnancy type. Women with MP gained less body fat during pregnancy to allow fetal growth.