Abstract: Three cases of the defibrination syndrome in pregnancy are reported: one occurred in association with abruptio placentae at 26 weeks, another in association with caesarean section for placenta praevia at 36 weeks, and the third in association with jaundice at 38 weeks.In all cases the clotting defect was reversed by the use of fibrinogen and all mothers and babies survived.The importance of timely diagnosis and treatment of the defibrination syndrome, even in unusual obstetric situations, is stressed.We should like to thank Professor uIn Donald for permission to publish these cases, and also Dr. M. L. N. Willoughby, under whose direction the blood tests were done and who has given us much helpful advice.