Endogenous hypercortisolism is a rare and one of the most severe endocrine disease, which is 4—5 times more common in women of reproductive age compared to men, therefore, the issues of pregnancy, gestation and delivery are of great importance. Due to the high prevalence of ovulatory function disorders with excessive cortisol secretion, the probability of pregnancy and especially childbirth in the active stage of endogenous hypercortisolism is extremely low. A favorable prognosis of the course of pregnancy and the outcome of childbirth is possible only with complete remission of the disease. Data on the onset of pregnancy in women with endogenous hypercortisolism remain isolated and are considered as unique clinical cases, especially in the presence of a history of malignant tumor processes. This article presents a clinical case of a patient with ectopic ACTH syndrome with the development of spontaneous pregnancy, which ended with the birth of a child. Achieving remission of the disease contributed to a favorable course and outcome of pregnancy. The presented case demonstrates the possibility of self-restoration of fertility, realization of reproductive function and gestation with favorable maternal and perinatal outcomes in women with ectopic ACTH syndrome and this is the first description in the Russian scientific literature.