Background: During pregnancy, the fetal stores for any nutrient are dependent on the maternal’s status for that nutrient. Maternal anaemia is associated with adverse birth outcomes along with maternal morbidity and mortality respectively. Similarly, elevated Hb levels may lead to diminished fetal and placental nutrient and oxygen supply resulting subsequently in fetal, placental, and maternal complications.
Objective: To explore (a) the relationship between event of fetal distress during term labour and intrapartum maternal haemoglobin level; (b) the relationship between mode of delivery, the reason for instrumental delivery and short-term neonatal outcome with maternal haemoglobin; and (c) Identify the factors influencing maternal haemoglobin level during the intrapartum period.
Materials and Methods: A retrospective cohort study was conducted in a tertiary care hospital set-up of a rural district at Karnataka, India. Data were obtained from women who underwent parturition during the 2017-2018 period respectively. A total of 7173 gravidas were included. Multivariate regression models with intrapartum Hb as the main independent variable of interest was used to determine the likelihood of fetal distress to occur in relation to intrapartum Hb level dependency wherein Hb was used as a continuous value. The likelihood of Instrumental Vaginal Delivery (IVD), cesarean section (CS), 5 min Apgar score <7, and umbilical cord arterial pH 7.05 to occur was analysed using a similar procedure. In addition; linear regression analytics was done to identify factors influencing intrapartum Hb level.
Results: Data of 7173 patients were analysed. Intrapartum Hb did not contribute to the prediction of the likelihood of fetal distress, IVD for non-progressive labour, CS for fetal condition, 5-min Apgar score <7, and pHa ≤ 7.05. However, there was a unique statistically significant contribution of Hb to the prediction of the likelihood of IVD for any reason and IVD for fetal distress and CS for any reason and CS for non-progressive labour. IVD for fetal distress was related to a higher intrapartum Hb level, whereas CS for non-progressive labour was related to a lower intrapartum Hb level. Factors identified to influence the intrapartum Hb level were maternal age, ethnicity, parity, fetal sex, and birth weight.
Conclusion: The risk of fetal distress and the adverse neonatal outcome is not correlated to intrapartum Hb levels. However, on the other hand, our data suggest that intrapartum Hb is a detrimental factor for a mode of delivery.
Keywords: Maternal haemoglobin; Fetal distress; Instrumental delivery; Neonatal outcome; Obstetric labour