Influence of assisted hatching on pregnancy outcomes in women with poor ovarian response: An RCT

Advances in assisted reproductive technology have led to improved outcomes through various innovations. The embryo must hatch from its acellular glycoprotein-based outer layer, the zona pellucida, before it can be implanted. Assisted hatching (AH) is a technique proposed to enhance embryo implantation.

This study aimed to evaluate the efficacy of AH in improving pregnancy outcomes among women with poor ovarian response (POR) undergoing in vitro fertilization/intracytoplasmic sperm injection.

A randomized controlled trial was conducted involving 170 women with POR (POSEIDON groups 3 and 4) undergoing in vitro fertilization/intracytoplasmic sperm injection at the Yazd Reproductive Sciences Institute, Yazd, Iran from December 2023-June 2024. Participants were randomly assigned to either the hatching group or the control group. Clinical pregnancy, chemical pregnancy, ongoing pregnancy, and miscarriage rates were compared between the 2 groups.

No significant difference was observed between the hatching and control group in terms of chemical pregnancy (24.4% vs. 17.3%. p = 0.271), clinical pregnancy (23.1% vs. 14.8%, p = 0.183), ongoing pregnancy (16.7% vs. 11.1%, p = 0.310), and miscarriage rates (27.8% vs. 25.0%, p = 0.866). However, a significant difference was observed in the frozen embryo transfer subgroup, with the hatching group demonstrating significantly higher rates of ongoing and clinical pregnancies compared to the control group.

While AH did not demonstrate overall benefits in improving pregnancy outcomes in women with POR, it may enhance the chances of ongoing and clinical pregnancy in frozen embryo transfer cycles.