Impact of Maternal Hemoglobin Concentration on Fetal Outcomes in Adolescent Pregnant Women

Background: Studies on the association between maternal hemoglobin (Hb) concentration and adverse pregnancy outcome have been inconsistent. Many studies have shown the impact of Hb concentration on pregnancy outcomes in adult women; however, it is not revealed in adolescent pregnant women. Objectives: The aim of this study was to examine the effect of Hb concentration on birth outcomes in pregnant adolescents as a high-risk group. Patients and Methods: In this cross-sectional study, 312 healthy and nonsmoker adolescent pregnant women with gestational age (GA) of 37-40 weeks were chosen by random sampling, and were followed until delivery. A complete history was obtained from women. In addition, clinical examination and Hb test were performed. After birth, the associations between Hb concentration during pregnancy and birth outcomes were investigated. Statistical analyses were performed using SPSS software by t-test, chi-square and ANOVA. Results: In total, about 23.2 % were anemic, 58% had normal level of Hb (11-13.2 g/dL) and 18.8% had Hb > 13.2 g/dL. The mean birth weight was 3197.8 ± 398.25 grams and it was more in mothers with Hb = 10.5-12.5 g/dL than others (Hb < 10.5 or Hb > 12.5 g/dL) (P < 0.001). The lowest mean birth weight was found in mothers with Hb < 10.5 (3033.33 ± 422). Moreover, the mean birth weight of male newborns was more than females (P = 0.001). Eight percent of neonates had Apgar score less than eight. Low Apgar score in anemic group and mothers with high Hb concentration (Hb > 12.5 g/dL) was more than others. Conclusions: Abnormal Hb concentrations increase the risk of adverse birth outcomes such as low birth weight (LBW) and low Apgar scores in pregnant adolescents, so intensive care is recommended for this group of pregnant women.