Trends in the twinning rate in Enugu, Nigeria.

Nigeria has the highest twinning rate in the world. Increasing twinning rates have been reported from various parts of the world as a result of assisted reproductive technologies. In order to determine whether Nigeria is part of this epidemic, the current study assessed the trends in twinning rates as seen at the University of Nigeria Teaching Hospital, Enugu, South-east Nigeria. It was a retrospective analysis of twin deliveries in the hospital over a 21-year period (1985-2005). No significant change was observed in the twinning rate within the study period. It was concluded that Nigeria is not yet part of the epidemic of multiple births affecting other parts of the world.