Multiple pregnancy as a risk factor in rural Tanzania.

The prevalence of twin pregnancies in two rural hospitals in the South Western Highlands of Tanzania ranged from 15 to 20 per 1,000 births. The literature on the generally assumed high twinning rates in the whole of Africa is reviewed. High prevalence figures can be the result of hospital selection, as most African studies are hospital-based. Only from Nigeria, one population-based study revealed a rate of 45 per 1,000. In both hospitals perinatal mortality in twin births was strikingly low, especially when birthweight was at least 1,500 g: between 30 and 40 per 1,000 births. It is argued that there is no place for a more liberal use of caesarean section to further reduce perinatal mortality.