PURPOSE: To analyze the influence of maternal nutritional status, weight gain and energy consumption on fetal growth in high-risk pregnancies. METHODS: A prospective study from August 2009 to August 2010 with the following inclusion criteria: puerperae up to the 5th postpartum day; high-risk singleton pregnancies (characterized by medical or obstetrical complications during pregnancy); live fetus at labor onset; delivery at the institution; maternal weight measured on the day of delivery, and presence of medical and/or obstetrical complications characterizing pregnancy as high-risk. Nutritional status was assessed by pregestational body mass index and body mass index in late pregnancy, and the patients were classified as: underweight, adequate, overweight and obese. A food frequency questionnaire was applied to evaluate energy consumption. We investigated maternal weight gain, delivery data and perinatal outcomes, as well as fetal growth based on the occurrence of small for gestational age and large for gestational age neonates. RESULTS: We included 374 women who were divided into three study groups according to newborn birth weight: adequate for gestational age (270 cases, 72.2%), small for gestational age (91 cases, 24.3%), and large for gestational age (13 cases, 3.5%). Univaried analysis showed that women with small for gestational age neonates had a significantly lower mean pregestational body mass index (23.5 kg/m², p<0.001), mean index during late pregnancy (27.7 kg/m², p<0.001), and a higher proportion of maternal underweight at the end of pregnancy (25.3%, p<0.001). Women with large for gestational age neonates had a significantly higher mean pregestational body mass index (29.1 kg/m², p<0.001), mean index during late pregnancy (34.3 kg/m², p<0.001), and a higher proportion of overweight (30.8%, p=0.02) and obesity (38.5%, p=0.02) according to pregestational body mass index, and obesity at the end of pregnancy (53.8%, p<0.001). Multivariate analysis revealed the index value during late pregnancy (OR=0.9; CI95% 0.8-0.9, p<0.001) and the presence of hypertension (OR=2.6; 95%CI 1.5-4.5, p<0.001) as independent factors for small for gestational age. Independent predictors of large for gestational age infant were the presence of diabetes mellitus (OR=20.2; 95%CI 5.3-76.8, p<0.001) and obesity according to body mass index during late pregnancy (OR=3.6; 95%CI 1.1-11.7, p=0.04). CONCLUSION: The maternal nutritional status at the end of pregnancy in high-risk pregnancies is independently associated with fetal growth, the body mass index during late pregnancy is a protective factor against small for gestational age neonates, and maternal obesity is a risk factor for large for gestational age neonates.
Nutritional status; Obesity; Pregnancy; Fetal development; Pregnancy, high-risk
