Caesarean section-rates of more than 10% in our days are not seldom; the reasons are the changed and enlarged indications for Caesarean section. The increase of the Caesarean section-frequency is parallel to the decrease of maternal mortality. The authors' investigations came to the same results. From 1963-1974 they examined 29534 deliveries (28184 spontaneous deliveries and 1350 Caesarean sections). In the examined years the Caesarean section-frequency increased from 3.6% to 5.7%. The maternal mortality of all deliveries was 5.47% (14 from 29534);the maternal mortality of the spontaneous vaginal deliveries was 0.14% (4 from 28184), in the Caesarean sections the maternal mortality was 7.41% (10 from 1350). The different causes of exitus in Caesarean section are discussed. Even "adjusted statistics" show that maternal mortality in Caesarean section is until today 10 to 15 times as high as in vaginal deliveries. Therefore Caesarean section means a ten times higher risk than a spontaneous delivery. For these reasons Caesarean section should not develop to the delivery's "method of choice" and we should keep our intentions also in future to the vaginal methods of delivery.