DURATION OF HUMAN SINGLETON PREGNANCIES IN IBADAN, NIGERIA

Analysis of gestation length in an obstetric population of indigenous African women revealed a mean pregnancy duration of 274.8 days, which is similar to values recorded in women of African descent elsewhere, b ut about 1 week less than what generally has been reported in women of European ancestry and Japanese women. Factors associated with lower p regnancy duration among these women include increasing maternal age an d gravidity, and the birth of a male infant. It is concluded that mean pregnancy duration in Nigerian women is shorter than the 280 days nor mally used in obstetric calculations. The consistent Finding of a shor ter length of gestation in these and other black women suggests earlie r maturity of the fetoplacental unit. Earlier institution of antepartu m Fetal monitoring in women of African descent, particularly women >30 years old and those with high parity, may reduce the risks of fetal m orbidity and mortality attributable to postmaturity in their offspring .