Gynecological cancer requiring management during pregnancy is rare, with an estimated incidence of 2 to 5 per 100,000 pregnancies in the first trimester. Balancing maternal and fetal health in these cases can be difficult, and management strategies differ from nonpregnancy cases. Management strategies are typically determined by maximizing benefit to the mother while minimizing harm to the fetus, considering the extent of the cancer, available treatment options for each type of cancer, and the gestational age of the fetus. This article is a guideline presenting the highest standard of evidence for the management of these cases, although the authors recognize that following these recommendations is not always possible in all areas of the world. These guidelines address imaging, pathology, surgery, medical oncology, obstetrics, radiation therapy, psychology, patient perspective, and pediatric follow-up for ovarian, cervical, and vulvar cancers during pregnancy.The guidelines in this article were developed using the European Society of Gynecological Oncology (ESGO) via the ESGO Guideline Committee. This consists of a multidisciplinary international development group that uses scientific evidence and expert consensus, as well as an external international review process. A systematic review was performed as part of the creation of these guidelines, including relevant studies published between January 2014 and June 2024. In cases where evidence was unclear, professional experience and expertise were used to fill the gap.General guidelines included discussing treatment with a multidisciplinary team, patient and partner counseling being a priority (including diagnostic and treatment plans, potential alternatives, risks and benefits, and side effects), workup and treatment being conducted at a specialized center, patients receiving care as close as possible to nonpregnant patients, taking into account individual modifications as necessary, prioritizing research with these cases, and registration of all cancer cases during pregnancy. The incidence of cancer during pregnancy is not decreasing, and thus, practitioners should be aware of these possible complications of pregnancy. Recommendations include investigating symptoms of cancer immediately and thoroughly, as well as preserving the pregnancy because pregnancy does not worsen the prognosis of gynecological cancers.Imaging guidelines include ultrasound examination for diagnosis, with the reassurance of its safety during pregnancy, magnetic resonance imaging (MRI) for inconclusive ultrasound examination, referral to an experienced radiologist, repeated ultrasound examination for management planning, using ultrasound to evaluate patient response to neoadjuvant chemotherapy, and avoiding the use of gadolinium-based contrast agents, using diffusion-weighted MRI instead. In addition, the use of a lead apron for shielding is not recommended.The recommendations surrounding pathology include recording all relevant information on the pathology request form, referral for specialist opinion, and submission of the placenta for pathological examination after delivery. Surgical recommendations include locoregional anesthesia as a preferred method over general anesthesia and using a left lateral tilt of at least 15 degrees after 20 weeks of gestation. If procedures cannot be postponed, they should be performed during pregnancy even with an elevated risk to the fetus, though trauma to the uterus should be avoided. Minimally invasive procedures are preferred during pregnancy, when possible, though there is little evidence surrounding safe lengths and abdominal pressures; thus, surgical times and abdominal pressure should be minimized.Medical oncology guidelines include assessment of maternal and fetal health before each chemotherapy cycle, choosing a chemotherapy regimen based on cancer type, adapting standard treatment due to anticipated fetotoxic effects, and timing of chemotherapy to be after 12 weeks of gestation and before 35 weeks of gestation. In terms of obstetrics, it is recommended to encourage the use of compression stockings or devices during surgery and prophylactic low-molecular-weight heparin both after surgery and after delivery. Preterm birth should be avoided if possible, and delivery should be timed 2 weeks after the last course of chemotherapy if possible. If preterm delivery is expected, corticosteroids should be administered for fetal lung development in accordance with standard care recommendations. Cesarean delivery is recommended in cases of vulvo-vaginal cancer in situ and invasive cervical cancer, and vaginal delivery can be considered in cases where cancer has been completely removed or is restricted to the ovaries.The effects of radiation should be considered in a risk/benefit assessment for this therapy during pregnancy, and pelvic or groin radiation therapy should not be performed if pregnancy preservation is desired. Limited delay of radiation therapy should be considered if it allows for standard treatment, but minimizing fetal exposure can be considered as well in urgent cases. If pregnancy preservation is not desired, radiation therapy in combination with feticide or uterine evacuation can be proposed.Oncopsychologists should be included in the multidisciplinary team managing cases of gynecological cancer in pregnancy, and regular screening should be performed along with support offered at every stage of treatment during and after pregnancy. Patients and their partners should be included in treatment decisions and educated and consulted about their care. Long-term monitoring is recommended for children exposed to chemotherapy or radiation in utero, including assessments of hearing, cardiotoxicity, and neurodevelopmental delays.