Maternal nutrient intake and maternal serum micronutrients and their relation to birth weight-a longitudinal study

Micronutrients are well known to play an important role in the maintenance of health. Alterations in maternal-fetal disposition of some essential micronutrients could be a potential health risk for mother as well as the fetus. A longitudinal study was conducted in Khoy city located in North West of Iran to investigate maternal nutrient intake and maternal serum micronutrients and their relation to birth weight. Nutrient intake was computed based on 24 hour recall method. During the three trimesters of pregnancy, blood specimens were collected from 162 healthy pregnant women aged 16-40 years and from cord blood of their neonates. The mean age of studied pregnant women was 26 [+ or -] 5years, and the mean birth weight of neonates was 3.3 [+ or -] 0.4 kg. Maternal serum levels of calcium, iron, zinc and copper were determined by an inductively couple plasma mass spectrometer (ICP/MS). The results showed that majority (41%) of pregnant women were in age group 26-36 years Fifty-five percent had high school and diploma levels of education and the total income of a majority of them was Rials 3-5 million per month. Anthropometric measurements, namely, height, weight, body mass index and upper mid arm during three trimesters of pregnancy showed significant differences except height according to different trimesters. The Mean energy, protein, calcium, iron, zinc, and copper were 2186 kcal, 74.5 g, 855.6 mg, 79.69, 12.3 mg and 1.58 respectively. Percentage adequacy of energy and protein intakes with reference to RDA recommendation showed 85% and 80% of subjects had sufficient RDA intakes, while calcium and zinc intake considered as insufficient. Energy, protein, calcium, zinc and iron intakes in the third trimester were significantly associated with birth weight of neonates. Regarding micronutrients, results indicate that iron levels decreased significantly from first to second trimester and significantly increased in third trimester. Serum zinc levels of subjects significantly decreased gradually during the first, second and third trimester. Serum copper levels increased significantly with increasing the gestational period. Calcium serum levels during three trimesters were constant. Maternal calcium, iron and zinc serum levels were associated with birth weight of neonates. Using Binary test the findings showed that calcium, protein, iron and energy intake as a predictor intake of pregnant women could be considered as primary "predictor factors" for birth weight of n