Summary. In 89 women with polycystic ovary syndrome (PCOS) who conceived after ovarian electrocautery, the pregnancy continued beyond 31 weeks in 62. In this group the frequency of pre-eclampsia and diabetes was 12·9 and 8·1% respectively. The increased frequencies were confined to overweight women. The frequency of major and minor malformations was 1% and 3·8% respectively. The rate of early miscarriage of the first pregnancy after ovarian electrocautery was 15%, and when later pregnancies were included the rate reduced to 10·3%. These data do not indicate any impact upon the course or outcome of pregnancy from the state of PCOS per se or the ovarian electrocautery that induced ovulation in this series.