This prospective, observational study investigated the incidence of irregular cleavage (IRC) among human embryos and its influence on IVF treatment outcomes. It included 1001 women who underwent 1976 assisted reproduction treatments during 2016–2021 in a single IVF clinic. Embryo morphokinetics were analyzed and evaluated for the association between IRC and women’s characteristics, treatment characteristics, and pregnancy outcomes. The incidence of IRC was 17.5% (1689/9632 embryos). Of these, 85% of the embryos had one IRC, 15% had multiple IRC and 35% of IRC events occurred during the embryo’s first cell cycle. IRC embryos were found to correlate with male factor (p = 0.01) and higher ICSI rate (p = 0.01). Age, BMI, parity, basal FSH level, stimulation protocol, and number of retrieved oocytes did not differ between groups. Embryos with early IRC or more than one IRC had lower blastulation rates (p = 0.01 for each). Fresh cycles with IRC embryos had a lower clinical pregnancy rate (p = 0.01) and embryos with early IRC had a lower live birth rate (p = 0.04) compared to embryos without IRC. Frozen transfer cycles of blastocyst embryos, with or without IRC, had comparable results. In conclusion, the number of abnormal cleavage events and their timing are important factors in the prognosis of the developing human embryo.

This prospective, case-control study evaluated the impact of obesity on oocyte quality based on mtDNA expression in cumulus cells (CC), and on bone morphogenetic protein 15 (BMP-15) and heparan sulfate proteoglycan 2 (HSPG2) in follicular fluid (FF). It included women 18 to <40 years of age, divided according to BMI < 24.9 (Group 1, n = 28) and BMI > 25 (Group 2, n = 22). Demographics, treatment, and pregnancy outcomes were compared. The mtDNA in CC, BMP-15, HSPG2, the lipid profile, the hormonal profile, and C-reactive protein were evaluated in FF and in blood samples. The BMP-15 levels in FF and the mitochondrial DNA in CC were higher in Group 1 (38.8 ± 32.5 vs. 14.3 ± 10.8 ng/mL; p = 0.001 and 1.10 ± 0.3 vs. 0.87 ± 0.18-fold change; p = 0.016, respectively) than in Group 2. High-density lipoprotein levels in blood and FF were higher in Group 1 (62 ± 18 vs. 50 ± 12 mg/dL; p = 0.015 and 34 ± 26 vs. 20.9 ± 7.2 mg/dL; p = 0.05, respectively). Group 2 had higher blood C-reactive protein (7.1 ± 5.4 vs. 3.4 ± 4.3 mg/L; p = 0.015), FF (5.2 ± 3.8 vs. 1.5 ± 1.6 mg/L; p = 0.002) and low-density lipoprotein levels (91 ± 27 vs. 71 ± 22 mg/dL; p = 0.008) vs. Group 1. Group 1 demonstrated a trend toward a better clinical pregnancy rate (47.8% vs. 28.6%: p = 0.31) and frozen embryo transfer rate (69.2% vs. 53.8; p = 0.69). Higher BMI resulted in lower BMP-15 levels and reduced mtDNA expression, which reflect decreased oocyte quality in overweight women.

This retrospective cohort study assessed the association between nuchal cord and adverse outcomes during vacuum-assisted delivery (VAD). Women with singleton pregnancies, 34–41-weeks gestation, who underwent VAD, from 2014 to 2020 were included. The primary outcome was umbilical cord pH ≤ 7.1. Secondary outcomes were neonatal intensive care unit admission, Apgar scores, pH < 7.15, subgaleal hematoma, shoulder dystocia and third/fourth-degree perineal tear. Outcomes were compared between neonates with (1059/3754, 28.2%) or without (71.8%) nuchal cord after VAD. No difference in cord pH ≤ 7.1 was found between groups. The nuchal cord group had a lower rate of nulliparity (729 (68.8%) vs. 2004 (74.4%), p = 0.001) and higher maternal BMI (23.6 ± 4.3 vs. 23.1 ± 5, p = 0.017). Nuchal cord was associated with higher rates of induction (207 (19.5%) vs. 431 (16%), p = 0.009) and lower birthweights (3185 ± 413 vs. 3223 ± 436 g, p = 0.013). The main indication for VAD in 830 (80.7%) of the nuchal cord group was non-reassuring fetal heart rate (NRFHR) vs. 1989 (75.6%) controls (p = 0.004). The second stage was shorter in the nuchal cord group (128 ± 81 vs. 141 ± 80 min, p < 0.001). Multivariate regression found nulliparity, induction and birthweight as independent risk factors for nuchal cord VAD. Although induction and NRFHR rates were higher in VAD with nuchal cord, the rate of umbilical cord acidemia was not.

Background: In this research, we retrospectively studied the influence of the IVF vs. the ICSI technique on embryo morphokinetics by means of a time-lapse incubator in fresh cycles. Methods: A total of 2645 treatment cycles resulting in ovum pick-up of 11,471 fertilized oocytes were included in the research from 2018 to 2022. The embryos were grouped according to IVF or ICSI. Embryonic development was monitored using a time-lapse incubator, and they were transferred on day 3 or 5. Results: The embryos in the ICSI group developed faster and had less fragmentation. However, fewer 2PNs were achieved and more embryos were discarded compared to IVF. When sibling oocytes treated with either IVF or ICSI were analyzed, we found that ICSI resulted in quicker development and higher KIDScores. Discussion: The anovulation and PCOS subgroups were the primary contributors to the high KIDScores in sibling oocytes, indicating that ICSI might have beneficial effects on oocyte factors, similar to the positive results it provides when male factors are involved. Conclusions: Women with PCOS undergoing IVF had better results when ICSI was used compared to spontaneous IVF. This study reveals that ICSI is superior to IVF in female factor infertility.

This study investigates the incidence of irregular cleavage (IRC) among human embryos and their influence on IVF treatment outcomes. This study was designed as a prospective observational study in a single-centre IVF clinic including 1,001 women who underwent 1,976 assisted reproduction treatments during 2016–2021. Morphokinetics of embryos was analysed and evaluated for the association between IRC and women’s characteristics, treatment characteristics, and pregnancy outcome. We found IRC incidence to be 17.5% (1,689/9,632 embryos). Of these, 85% embryos had one IRC, and 15% had multiple IRC. 35% of IRC events occurred during the embryo's first cell cycle. IRC embryos were found to correlate with male factor (p = 0.01) and higher ICSI rate (p = 0.01). Age, BMI, parity, basal FSH level, stimulation protocol and number of retrieved oocytes did not differ between groups. Embryos with early IRC or more than one IRC event had lower blastulation rate (p = 0.01 and p = 0.01, respectively). Fresh cycles with IRC embryos had a lower clinical pregnancy rate (p = 0.01), and early IRC embryos had a lower live birth rate (p = 0.04) compared to embryos without IRC. Frozen embryo transfer (FET) cycles of blastocyst embryos, with and without IRC, had comparable results. In conclusion, number of abnormal cleavage events and their timing are of great importance for the prognosis of the developing human embryo.