Chocolate cysts may affect pregnancy. Ovarian chocolate cysts are ovarian-type endometriosis, with approximately 80% of lesions involving one side and 50% of patients having bilateral ovarian involvement. The ectopic endometrium causes periodic bleeding, which in turn leads to enlargement of the ovary and the formation of single or multiple cysts. The cysts tend to be 5-6 cm in diameter, with the largest ones reaching about 25 cm in diameter. The cysts contain brown, sticky, old blood that resembles chocolate paste, hence the name ovarian chocolate cysts. After rupture of the chocolate cyst, its contents can stimulate the local peritoneum, resulting in local inflammation and tissue fibrosis, leading to close adhesions between the ovary and the surrounding tissues, limiting the movement of the ovary fixed in the pelvic cavity, which can lead to infertility of the patient if it leads to tubal adhesions or atresia. In addition, when a large ovarian endometriotic cyst ruptures, its contents flow into the pelvic cavity and the patient may experience sudden and severe abdominal pain accompanied by nausea and vomiting, which can cause acute abdominal disease. Therefore, for larger chocolate cysts that cause infertility, surgical treatment such as laparoscopic surgery to remove the lesion and pregnancy as soon as possible after the surgery can be chosen. In the case of smaller chocolate cysts, which have less impact on fertility, pregnancy can be actively prepared under the guidance of an obstetrician.