Endometriosis is a disease that has a profound impact on the quality of life of women, due to the associated chronic pelvic pain, dysmenorrhea, dyspareunia and infertility. However, even getting long-awaited pregnancy (often after assisted reproductive technologies), patients with endometriosis have a high risk of obstetric complications, such as miscarriage, preterm birth, preeclampsia, placental abnormalities, hemorrhage in labor, birth of small for gestational age infants, stillbirth and higher cesarean section rate. In addition, during pregnancy acute complications of endometriosis may occur, such as spontaneous hemoperitoneum, which is rare but life-threatening conditions that in most cases require surgical intervention. The mechanisms of the observed complications in pregnant women with endometriosis are not fully understood. This review presents literature data and personal considerations on the effect of endometriosis on pregnancy outcome and the occurrence of complications, as well as their possible underlined mechanisms. Based on this, we proposed ways to reduce the risk of obstetric complications in pregnant women with a history of endometriosis.