Maternal Anaemia as a risk factor for Preterm Births in Mulago National Referral hospital, Uganda : A Case-control study

Abstract

Introduction: Preterm birth is a perplexing life event; it poses a lot of anxiety to the family, who remain uncertain of their child’s future health and development. Prematurity is a syndrome associated with a high neonatal morbidity and mortality, with adverse complications later in life. The aetiology of preterm births is multifactorial; and the association between maternal anaemia and preterm birth remains equivocal with some studies documenting increased risk, but not others. Understanding maternal anaemia and its causal relationship with preterm delivery, is key in the designing of focused innovations of care and strategic prevention interventions to improve maternal and perinatal outcome. Objective: The study was to determine the strength of association between anaemia during pregnancy and delivery of a preterm baby. Methods: This was an unmatched case control study, conducted in the, high risk Obstetric labour suit, postnatal ward and Neonatal special care unit of Mulago National Referral Hospital. 220 mothers who fulfilled the eligibility criteria, were recruited and studied; cases were selected by consecutive sampling technique while controls by systematic random sampling method, in a ratio of 1:1. A standardized questionnaire was used to collect data. Blood samples were collected from all mothers, within 24 hours of delivery for haemoglobin concentration testing and peripheral film assessment for only those diagnosed with anaemia. Data analysis was done using STATA version 13.0. Logistic regression analysis was used to analyze the strength of association between preterm birth and maternal anaemia.

Results: The odds of delivering a preterm baby were 2.7 times higher in women with an Hb <11.0g/dl compared to women with an Hb >11.0g/dl. This was significant with a p-value of 0.016 and 95% CI (1.2-6.05). For every unit increase in MUAC, the odds of having a preterm birth reduce by 16%, with p-value < 0.001, and 95% CI (0.73 – 0.91).

Conclusions: Maternal anaemia was an independent risk factor for preterm birth among the mothers who delivered in Mulago hospital; and normocytic normochromic type of anaemia was the most common. Also, a MUAC > 18 cm was found to be protective of preterm delivery.