The effect of maternal glucose metabolism, iron, vitamin B12 and folate status on pregnancy outcomes

Objective. To evaluate the effect and consequences of certain maternal factors (nutritional, sociodemographic and glucose metabolism) on pregnancy outcome of women recruited during the third trimester. Design. A longitudinal analytical study. Setting. Villages in the central region of the Limpopo province. Subjects. Third-trimester pregnant women attending prenatal clinics at nine local clinics in the villages (N = 219) and their newborn infants. Results. The study showed that predictors of birth weight were found to be maternal body mass index (BMI), beta-cell function, haemoglobin and ferritin levels, while birth length was predicted by maternal height, fasting glucose and ferritin. The models accounted for 12.4% and 8.6% of the variation in both birth weight and length respectively. The 30-minute glucose (5.56 ± 1.31; 6.23 ± 1.59 mmol/l; p = 0.027) and haemoglobin levels (12.22 ± 1.76, 11.46 ± 1.87 g/dl; p = 0.041) differed significantly between the first and third birth weight tertiles. With respect to birth length tertiles, fasting (4.18 ± 0.55, 3.84 ± 0.92 mmol/l; p = 0.045), 30-minute (5.72 ± 1.24, 6.31 ± 1.50 mmol/l; p = 0.047) and 2-hour glucose levels (5.04 ± 1.32, 6.13 ± 2.50 mmol/l; p = 0.004) differed significantly between the first and third tertiles. Conclusion. The study showed that normal glucose metabolism is essential for the optimal growth of the fetus with respect to attained weight and length at birth. Furthermore, maternal stature and iron status (as measured by haemoglobin and ferritin levels) appear to be playing vital roles in predicting both birth weight and length. South African Journal of Clinical Nutrition Vol. 19(3) 2006: 120-13