If there is no menstruation after ovarian cyst surgery, it may be due to pregnancy, endocrine disorders, premature ovarian failure and other reasons, which need to be analyzed specifically. 1. Pregnancy: If you have unprotected sex after ovarian cyst surgery, then pregnancy may occur, resulting in menstruation not coming on time. 2. Endocrine disorders: Ovarian cyst surgery will stimulate the body, and the endocrine system, after being stimulated, may have temporary hormone secretion abnormality, resulting in delayed menstruation, which may become normal after a period of postoperative recovery. 3. Premature Ovarian Failure: If the ovarian function decreases after the surgery, estrogen secretion may be insufficient, resulting in the absence of menstruation. If a woman’s menstruation changes after surgery for ovarian cysts, there may be other reasons, so it is recommended that she consult a doctor in time, complete the relevant examinations, clarify the cause of the disease under the guidance of the doctor, and take standardized methods of treatment.