The impact of endometriosis on embryo morphokinetics: embryos from endometriosis patients exhibit delayed cell cycle milestones and decreased blastulation rates.

ABSTRACT

PURPOSE: To compare morphokinetic parameters in embryos obtained from women with and without endometriosis. METHODS: We evaluated a total of 3471 embryos resulting from 434 oocyte retrievals performed at a single academic center. One thousand seventy-eight embryos were obtained from women affected by endometriosis and 2393 came from unaffected controls. All embryos were cultured in a time-lapse incubator chamber for up to 6 days. IVF cycle outcomes and morphokinetic parameters collected prospectively were retrospectively reviewed. RESULTS: Morphokinetic data suggest that embryo development is impaired in embryos obtained from women with endometriosis (EE). EE were slower to achieve the 2-8 cell stages compared to control embryos (CE) (p < 0.001); additionally, time to compaction was delayed compared to CE (p = 0.015). The timing of late developmental events, including morulation and blastulation was also delayed in the endometriosis cohort (p < 0.001). In addition to demonstrating delayed cell cycle milestones, EE were less likely than controls to progress to morula, blastocyst, and expanded blastocyst stages (p < 0.001). Furthermore, a smaller proportion of embryos in the endometriosis group fell into optimal kinetic ranges for cc2 (p = 0.003), t5 (p = 0.019), tSB (p < 0.001), and tEB (p = 0.007). There were no significant differences in clinical pregnancy or live birth rates between groups. CONCLUSION: Embryos from endometriosis patients demonstrate impairments in both early and late developmental events, and progress to the morula, blastocyst, and expanded blastocyst stages at lower rates than control embryos. Despite these differences, IVF outcomes are similar for patients with and without endometriosis.