Maternal Hemoglobin Levels during Pregnancy and their Association with Birth Weight of Neonates.

BACK GROUND: Anemia in pregnancy is associated with increased rates of maternal and perinatal mortality, premature delivery, low birth weight, and other adverse outcomes.

MATERIALS AND METHODS: A prospective study was conducted on 1405 Iranian pregnant women who delivered during 2015. Blood was collected from all the subjects to measure the hemoglobin (Hb) during 16-19 weeks, 22-24 weeks, and 34-36 weeks of gestation. According to the level of hemoglobin, it is divided into 4 groups. Group 1; Hb > 10.1 gm/100ml (control group), Group 2; Hb= 8.1-10 gm/100ml (mild anemia) Group 3; Hb= 6.5-8 gm/100ml (moderate anemia) Group 4; Hb <6.5 gm/100ml (severe anemia). After delivery, the neonates were weighted within 24 hours after birth. Maternal hemoglobin and birth weights were compared.

RESULTS: The anemia prevalence was 20.2% (Hb<10g/dl). Out of them, 16.2 % hadmoderate anemia (Hb=6.5-8 g/dl) and 83.8% had mild anemia (Hb=8.1-10 g/dl). Severe anemia did not detect in pregnant women. The hemoglobin levels in non anemic group showed a drop in the second trimester. Pregnant women with hemoglobin less than 10 g/dl, considered as anemic gave birth to neonates with birth weight of 2.6kg, while pregnant women with higher hemoglobin level (>10 g/dl), considered as normal gave birth to heavier and normal babies (3.3 kg). The severity of anemia during three trimesters was closely associated with birth weight of newborns.

CONCLUSION: The low hemoglobin values during three trimesters of pregnancy were associated with low birth weight in Iran. The anemia can lead to intra uterine growth retardation.