Study of fetal hemoglobin with different gestational age and birth weight of the newborn

Abstract

Background: In many parts of the developing country estimation of antenatal gestational age is still not possible and challenging condition of proper perinatal care. This study aimed to find out relationship between the gestational age and birth weight of the newborn with fetal hemoglobin concentration.Methods: In this comparative study, we included 90 pregnant women who delivered their babies by normal vaginal delivery. Out of these 90 babies, 27 were preterm with gestational age 28-36 weeks, 55 were term with gestational age 37-41 weeks and remaining 8 were post term with gestational age of more than 41 weeks. All these 90 newborn infants were also divided into two groups: low birth weight (birth weight <2.5 kg) and birth weight ≥2.5 kg. Fetal hemoglobin was estimated by using alkali denaturation technique of Chernoff and Singer on appropriate spectrophotometer. Statistical analysis was performed using SPSS windows version 20.0 software.Results: The total number of newborns were significantly (p<0.001) higher in term group and with normal birth weight group. Fetal hemoglobin level was significantly (p<0.0001) lower in term, post term and normal birth weight groups. Study showed a definite negative correlation between gestational age and the fetal hemoglobin concentration. Fetal hemoglobin level was gradually declining with increasing gestational age and birth weight.Conclusions:  It is concluded from this study that the concentration of fetal hemoglobin decreases at the rate of 2.4% per week with considerable variation of values at every week of advancing gestational age. Hence level of fetal hemoglobin estimation can be taken as an important criterion for evaluation of gestational age.