Diathermocoagulation is not a therapeutical procedure devoid of risk. Its indication should take into account potential drawbacks: infection episodes, haemorrhage and, first of all, sclerosing scarrs of the chorion that can give rise to pavimentous keratosis, stencsis, synechiae, cervicale sterility. A particular complication is the development of endometriosis: exocervical in the first place but that can also involve the uterosacral ligaments, the rectovaginal septum or even the uterus or pelvis. More especially it can mask the incipient syndromes of cervical carcinoma and its prophylactic value as far as this cancer is concerned appears questionable. For all these reasons, the authors insist in the precautions that must be taken prior to diathermocoagulation of the cervix uteri and for its implementation.