Seventy-seven women had 98 pregnancies after a cone biopsy of the cervix. There were 62 deliveries, 26 legal abortions, 9 spontaneous abortions and 1 ectopic pregnancy. Cervical cerclage was done for 22 out of 62 conized parturients (35.4%) and for none in the matched control group. There were 4 (6.4%) preterm deliveries in the cone biopsy group and 1 in the control group. The perinatal mortalities were 3.2% and 0% respectively. The mean duration of labour was 2.4 h shorter in the conized parturients than in the controls (P < 0.05) but there were no difference in the mode of delivery in the two groups.