With the aim of studying the causes of peculiarities of female reproductive function and secondary sterility as a result of 100 cesarean sections by M. Stark's modified method, we have attempted to determine the immune status of organisms of women in post-operational period, in post-operational purulent septic complications and in post-operational process of uterus involution. As a result of hysteroscopy and metrosalpingographic tests it has been established that a secondary sterility after cesarean section carried out according to M. Stark modification is manifested 2.5 times less than after traditional method of cesarean section which widely used nowadays.