Objective: To determine the risk of adverse maternal outcome associated with obstetric intervention in labour.Methods:All cases of macrosomic births conducted at the University of Calabar Teaching Hospital,Calabar,between January 1st 1994 and December 31st 2000 were reviewed.Measure of treatment/intervention effect was calculated as relative risk for adverse maternal outcome,using spontaneous vaginal births as control.Results:Frequency of mode of delivery was as follow: vaginal births,139(60.7%);instrumental vaginal deliveries,16(7%);and abdominal deliveries,74(32.3%).Obstetric intervention occurred in 90(39.3%) cases.Sixty-four(28%) cases did not book for antenatal care,with 42 cases(18.3%) requiring obstetric intervention.About one in every two parturients(1: 2.1) in this study,requiring obstetric intervention at delivery had been interfered with at unorthodox health facilities.Relative risks for postpartum haemorrhage,wound sepsis and paralytic ileus were significantly high in parturients with abdominal delivery;while in parturients with instrumental vaginal delivery relative risks were significantly high for puerperal sepsis,paralytic ileus and obstetric palsy.There were no maternal deaths.Conclusion:Obstetric intervention in parturients with macrosomic births was high due to labour complications;and was associated with significant risk for adverse maternal outcome,especially in parturients with unskilled interference. Objective: To determine the risk of adverse maternal outcome associated with obstetric intervention in labor. Methods: All cases of macrosomic births conducting at the University of Calabar Teaching Hospital, Calabar, between January 1st 1994 and December 31st 2000 were reviewed. Measurement of treatment / intervention effect was calculated as relative risk for adverse maternal outcome, using spontaneous vaginal births as control. Results: Frequency of mode of delivery was as follow: vaginal births, 139 (60.7%); instrumental vaginal deliveries, 16 (7%); and Obstetric intervention occurred in 90 (39.3%) cases did not book for antenatal care, with 42 cases (18.3%) requiring obstetric intervention. About one in every two parturients (1: 2.1) in this study, requiring obstetric intervention at delivery had been interfered with at unorthodox health facilities. Reciprocal risks for postpartum haemorrhage, wound sepsis and paralytic ileus were significantly high in partu rients with abdominal delivery; while in parturients with instrumental vaginal delivery relative risks are significantly high for puerperal sepsis, paralytic ileus and obstetric palsy.There were no maternal deaths.Conclusion: Obstetric intervention in parturients with macrosomic births was high due to lab complications; and was associated with significant risk for adverse maternal outcome, especially in parturients with unskilled interference.