Risk factors for prematurity at Harare Maternity Hospital, Zimbabwe

Background Prematurity remains the main cause of mortality and morbidity in infants and a problem in the care of pregnant women world-wide. This preliminary study describes the socio-demographic, reproductive, medical, and obstetrical risk factors for having a live pre-term delivery (PTD) in Zimbabwe. Methods This case-control study examined risk factors for PTD, at Harare Maternity Hospital between March and June 1999. Results The frequency of PTD among live birth was 16.4%. Prior history of stillbirth or abortion was associated with PTD (adjusted relative risk [ARR] 1.50; 95% CI: 1.06, 2.11). Nutritional factors, including drinking a local non-alcoholic beverage (mahewu) during pregnancy and mother's increasing mid-arm circumference reduced the risk of PTD (ARR = 0.75; 95% CI: 0.60, 0.93 and ARR = 0.95; 95% CI: 0.92, 0.99 per cm of circumference, respectively). Obstetric conditions including eclampsia, anaemia, ante-partum haemorrhage, and placenta praevia were infrequent, but when present, were strongly associated with PTD (ARR = 3.57; 95% CI: 1.67, 7.63; ARR = 4.12; 95% CI: 1.80, 9.43; ARR = 3.05; 95% CI: 1.86, 5.00 and ARR = 3.30; 95% CI: 1.34, 8.14, respectively). Malaria, although less frequent, nonetheless was associated with an increased risk of PTD (ARR = 2.93; 95% CI: 1.70, 5.04). These results suggest that in addition to established obstetric risk factors, nutrition and malarial infection are important. About 43% of the mothers initiated prenatal care after 28 weeks of gestation. Conclusion Addressing prematurity in this population will require earlier initiation of prenatal care to allow for early detection and management of complications of pregnancy, and improving nutritional status of reproductive age with locally available foods. Further exploration of the potential benefits of mahewu, is warranted.