The impact of paternal factors on cleavage stage and blastocyst development analyzed by time-lapse imaging—a retrospective observational study

Abstract

Purpose Various time-lapse studies have postulated embryo selection criteria based on early morphokinetic markers. However, late paternal effects are mostly not visible before embryonic genome activation. The primary objective of this retrospective study was to investigate whether those early morphokinetic algorithms investigated by time-lapse imaging are reliable enough to allow for the accurate selection of those embryos that develop into blastocysts, while of course taking into account the correlation with the type of injected spermatozoa. Methods During a period of 18 months, a total of 461 MII oocytes from 43 couples with severe male factor infertility and previous Bexternal^IVF failures after cleavage-stage embryo transfer (ET) were fertilized by intracytoplasmic morphologically selected sperm injection (IMSI). Thereof, 373 embryos were monitored in a time-lapse incubator until ET on day 5. Blastocyst outcome in combination with three previously postulated MKc (cc2: t3-t2, 5-12 h; t3, 35-40 h; t5, 48-56 h) and the morphology of the selected sperm were analyzed. Results A significant increase in the rate of blastocysts (54.0 vs. 36.3 %; P<0.01) and top blastocysts (25.3 vs. 10.8 %; P<0.001) was observed in the group of those meeting all three morphokinetic criteria (MKc3). However, MKc3 were only met in 23.3 % of all embryos. Moreover, TBR was influenced by the type of injected spermatozoa. In both groups, TBR decreased dramatically (MKc3, 35.0 vs. 17.0 %; MKc<3, 14.2 vs. 8.4 %) when class II/III sperm instead of class I were injected. Conclusion Early morphokinetic parameters might give some predictive information but fail to serve as a feasible selective tool for the prediction of blastocyst development given the influence of the type of spermatozoa injected.

Are blastocyst aneuploidy rates different between fertile and infertile populations?

“…This may suggest that if these patients and their arrested embryo cohorts were included, it may further affirm our findings. Our finding that patients with an indication of male factor infertility having significantly fewer blastocysts available for biopsy than maternal age-matched cohorts with different indications has been previously observed in both donor and autologous oocytes [14,15] and may be related to the paternal contribution to transcription after the 8-cell stage [16].…”

High rates of aneuploidy, mosaicism and abnormal morphokinetic development in cases with low sperm concentration

“…Abnormal sperm parameters and chromatin alteration affect the normal embryo kinetics in ICSI program. Several studies have examined the morphokinetic development of embryos in SMF cases [33][34][35][36][37]7]. We, too, evaluated the morphokinetic development of embryos, but, in addition, investigated any possible correlation between morphokinetics and chromosomal status in SMF cases.…”

IMSI procedure improves clinical outcomes and embryo morphokinetics in patients with different aetiologies of male infertility

“…It has been shown that IMSI could improve the IVF results in patients with previous ICSI failures. The pregnancy rate was shown to increase in cases with more than two failed ICSI attempts, also in female infertile with unexplained reasons for failure after ICSI with normal spermatozoa (Kim et al, ; Leandri et al, ; Neyer et al, ).…”