Effect of Cervical Mucus Quantity at Time of Embryo Catheter Transfer on IVF Pregnancy Outcomes

Abstract

BACKGROUND: PRemoval of cervical mucus at the time of embryo transfer has been associated with increased pregnancy rates. Previous reports focus on presence or absence of mucus. It is unknown if this association is due to plugging of the catheter, adherence of the embryos to the catheter or a marker of potential pathogens in the cervix. OBJECTIVE(S): To determine the relationship between amount of cervical mucus on the transfer catheter and embryo transfer outcomes. MATERIALS AND METHOD(S): A retrospective analysis was performed for all IVF embryo transfers conducted between January 2000 and December 2009. Included subjects were less than thirty five years of age and had cervical mucus documented at time of embryo transfer. Cervical mucus was documented by the embryologist at time of transfer as none, minimal, or significant. 2779 total embryo transfers occurred during the study period: 214 transfers had cervical mucus, of which 148 had minimal mucus and 66 had significant mucus. The two groups (minimal/significant) were compared and analyzed using JMP 8.0. Chi Square and Odds Ratios were performed. RESULT(S): 47 percent of subjects with significant mucus became pregnant compared to 61.5 percent of subjects with minimal mucus. Comparison of pregnancy rates between significant mucus versus minimal mucus yielded a Chi Square of 0.048 and Odds ratio of 1.82 (1.003 – 3.238). CONCLUSION(S): The quantity of cervical mucus documented at time of embryo transfer significantly affected pregnancy rate (P < 0.048). Patients were 1.8 times more likely to become pregnant when minimal cervical mucus was present at the time of embryo transfer versus significant. This difference found in pregnancy rates between significant cervical mucus and minimal cervical mucus demonstrates the importance of removing cervical mucus at the time of embryo transfer. Future studies addressing cervical mucus effect on IVF outcomes should focus on quantity in addition to the presence or absence of cervical mucus. SUPPORT: None