Exploring new frontiers in oncofertility preservation: a case of ovarian stimulation during pregnancy

The standard treatment for Pregnancy-Associated Breast Cancer (PABC) includes surgery and neoadjuvant chemotherapy, which can impair fertility, emphasizing the critical need for fertility preservation in these patients. This case report discusses a breast cancer patient who was found to be pregnant shortly after starting treatment. Despite the pregnancy and increased levels of βHCG and progesterone, the ovarian stimulation cycle yielded a satisfactory number of mature oocytes and high-quality embryos.

A 40-year-old woman, G1Ab1 (Gravida1Abortion1), who was diagnosed with Invasive Ductal Carcinoma with negative receptors (Estrogen Receptor, Progesterone Receptor, and Human Epidermal Growth Factor Receptor 2) was referred to the oncofertility unit of the Royan Infertility Center for fertility preservation prior to the commencement of chemotherapy. Following necessary consultations and procedures, and confirming a negative pregnancy test, a random start letrozole-based protocol was initiated for ovarian stimulation. During the cycle, a positive pregnancy test was encountered. Despite the positive test, the cycle continued, and on day 13 of the cycle, triggering was performed with a GnRH agonist. A puncture was performed 36 h later, yielding 12 oocytes and 8 embryos.

This case highlights the feasibility of adapting random-start ovarian stimulation protocols during pregnancy, warranting further investigation in similar clinical scenarios.