Twin births at University of Maiduguri Teaching Hospital: incidence, pregnancy complications and outcome.

In a five year retrospective study (between January 1990 and December 1994), there were 86 twin births out of 5,953 deliveries at University of Maiduguri Teaching Hospital giving a twin delivery incidence of 14.4/1000 birth. Only 82 case notes were available for this study. Dizygotic twins accounted for 80.5% of the cases while monozygotic twins represented 19.5% in the series. Increasing maternal age during the reproductive age and positive family history of multiple pregnancy were associated with increase twinning rate. The main complications encountered during pregnancy were hyperemesis gravidarum, pregnancy-induced hypertension and preterm labour. The frequency of preterm labour in this study was significantly higher than the observed among the singleton pregnancies within the period of study (P < 0.005). The perinatal mortality rate 85.4/1000 births was similarly significantly higher than that observed among the singleton deliveries (P < 0.005). Compared to singleton pregnancies there was a higher rate of caesarean section intervention (P < 0.005). The commonest mode of presentation and sex distribution were vertex-vertex and male-female respectively. The vertex-vertex presentation accounted for 48.8% of all the presentations while the male-female ratio was 1.2.