Advanced age woman with diminished ovarian reserve obtained live birth following a zero pronuclei-derived four-cell frozen-thawed embryo transfer on day 4: a case report.

Objective: Advanced maternal age and diminished ovarian reserve (DOR) are challenges in infertile patients for fertilization-embryo transfer (IVF-ET). This study aimed to investigate the pregnancy outcomes of women with advanced age and DOR undergoing low-quality embryo transfers.

Case Report: We report a rare case of successful pregnancy resulting from a zero pronuclei (0PN)-derived four-cell embryo transfer on day 4 (D4). An advanced age patient with DOR underwent five unsuccessful embryo transfers. A successful outcome was achieved when the patient underwent a hormone replacement FET cycle and received 0PN-derived four-cell frozen-thawed cleavage embryo transfer on D4. Fourteen days after the transfer, her serum β-human chorionic gonadotropin level was 575.3 mIU/mL. Subsequent prenatal examinations were normal, and the patient delivered a full-term healthy baby girl by caesarean section. Achieving a successful pregnancy after 0PN-derived four-cell frozen-thawed embryo transfer on D4 is rare. This increasingly exhibits significance for advanced age patients with DOR.

Conclusion: Selectively transferring embryos with slow growth but low fragments and no evident damage is beneficial for advanced age patients with DOR. For these individuals, obtaining embryos is challenging. Therefore, a personalized embryo transfer strategy should be considered to increase the possibility of pregnancy.