ASA 81 mg vs 162 mg During Frozen Embryo Transfer (FET)

Retrospective Study to Assess if Aspirin 162 mg is Better Than 81 mg for Embryo Transfer Outcomes

The use of low dose aspirin is recommended for high risk patients to reduce the risk of pre-eclampsia, placental abruption and antepartum hemorrhage. Recent studies have shown that in a specific population, the use of low dose aspirin might reduce the risk of preterm birth in pregnant women with singleton pregnancy. In June 2022, clinique ovo started implementing the use of Aspirin 162 mg instead of 81 mg in the frozen embryo transfer cycles based on recent study outcomes. The use of Aspirin 162 mg might have additional benefits on the embryo transfer outcomes by decreasing the miscarriage. Moreover this can be continued until late in pregnancy without adverse effects.

Inclusion Criteria:

• Women taking aspirin 81 mg or 162 mg prior to an autologous embryo transfer
• Age < 40 years old
• Embryo transfer cycle done at clinique ovo

Exclusion Criteria:

• Egg or embryo recipient
• History of recurrent miscarriages, defined as ≥ 3 consecutive losses
• Patients that needed Viagra, PRP or other modalities to improve their endometrial thickness
• Uterine factor infertility
• Abnormal hormonal profiles
• Stimulated embryo transfer cycles
• History of recurrent implantation failure defined as failed ≥ 2 euploid embryos transfer or ≥ 3 blastocysts