BNT162b2 Covid-19 vaccine does not affect fertility as explored in a pilot study of women undergoing IVF treatment.

BACKGROUND: The COVID-19 pandemic spreads worldwide, causing devastating consequences. BioNTech and Pfizer's BNT162b2 vaccine was one of the first vaccines to receive emergency-use authorization. However, its impact on women's fertility has not been primarily assessed leading to spread of unfounded rumors, causing vaccine hesitancy. We investigate the possible impact of BNT162b2 COVID-19 vaccine on in vitro fertilization (IVF) outcomes. METHODS: We compared data from 42 women undergoing their first IVF following 2 doses of BNT162b2 vaccination to 42 unvaccinated women undergoing their first IVF. The first outcome consisted of the pregnancy based on first hCG value; secondary outcomes were IVF cycle outcomes. A second analysis was done on 29 paired patients from both groups based on age, FSH, and the indication for IVF. RESULTS: We report different levels of the pregnancy formation; oocyte's development: numbers of oocytes retrieved (9.3±6.8 vs. 11.5 ± 7.9, p=0.19) and matured (6.9±4.8 vs. 9.1 ± 6.6, p=0.14), and embryonal stage: fertilization rates (64.1±26.6 vs. 66.3±23.3, p=0.14), the quantity (4.3 ± 3.2 vs. 5.7±4.4, p=0.23) and qualities of embryos (good/fair/poor) at day 3 were comparable. The analysis showed no significant difference between the groups, and the odds for pregnancy were similar (OR=0.9, 95% CL[0.3-2.8] p.value 0.833). CONCLUSIONS: From our results, this vaccine does not affect IVF performance and outcomes from the early stage of oocyte development through to the early beginning of pregnancy; therefore, it seems that the BNT162b2 vaccine does not compromise women's fertility.

Association between birth weight and head circumference and obstetric anal sphincter injury severity.

OBJECTIVE: To identify risk factors for increasing severity of OASI and evaluate its possible correlation with two known risk factors-birth weight (BW) and neonatal head circumference (HC). METHODS: We performed a retrospective cohort study at a university affiliated hospital between 2003 and 2019. We compared five groups of patients - according to presence and degree of perineal laceration - 3a, 3b, 3c and 4 and patients without OASI. Additionally, four parameters were defined to assess their relation to the severity of OASI: (1) BW ≥ 90th and HC < 90th percentiles; (2) BW < 90th and HC ≥ 90th percentile; (3) BW and HC ≥ 90th percentile and (4) BW and HC < 90th percentiles. RESULTS: During the study period, 150,221 deliveries were evaluated. Parturients were allocated according to OASI severity - 455 patients had a 3rd (3a, 3b or 3c) or 4th degree perineal tear, while 110,966 patients had no OASI. Allocation to subgroups according to offspring anthropomorphic measures showed that as fetal size parameters increased, the rate of more severe tears increased, particularly in women delivering neonates with HC ≥ 90th percentile. Multinomial regression analysis was performed for each 3rd degree OASI subgroup. This analysis demonstrated the odds for OASI gradually increase with tear severity for BW ≥ 90th percentile and the combined BW and HC ≥ 90th percentile parameters, as compared with neonates with HC and BW < 90th percentile. CONCLUSIONS: Birth weight and head circumference above the 90th percentile are correlated with increased degree of OASI severity.

Obstetric anal sphincter injury in adolescent mothers.

BACKGROUND: Obstetric anal sphincter injury (OASI) is a debilitating complication of vaginal delivery which has yet to receive ample attention in adolescents. The aim of this study was to describe risk for OASI in adolescent mothers compared to adults. We further attempted to compare risk factors for OASI between these two age groups. METHODS: We performed a retrospective cohort study between 2003 and 2019. Primiparous women who delivered vaginally, 21 years and younger were compared to women ages 26-35. Excluded were preterm, multifetal, non-vertex, cesarean deliveries as well as intrauterine fetal death. Rate of OASI as well as obstetric and labor characteristics of women with OASI, were compared between groups. Finally, risk factors were assessed for each group separately. Univariate and multivariate logistic regression model were performed. RESULTS: Final analysis was performed on 5113 nulliparous adolescents and 13,845 nulliparous in the 26-35 age group. Allocation to study groups was according to OASI - Sixty-seven adolescents (1.3%) had a 3rd or 4th degree perineal tear and were defined as the OASI group, while 5046 patients (98.7%) did not have such a tear. In the adult group, 199 out of 13,845 patients (1.4%) were diagnosed with OASI. Occurrence of OASI did not differ between groups (p = 0.510). Comparison of women with OASI in the adolescent group vs. adult group found differences with regard to operative vaginal delivery, (20.9% vs. 36.2%, respectively; p = 0.023) and meconium stained amniotic fluid (9.1% vs. 21.3%, respectively; p = 0.027). Following multivariate analysis the only parameter independently associated with OASI in the adolescent age group was head circumference ≥ 90th percentile with an adjusted odds ratio of 3.08 (CI 1.48-6.38, p = 0.003). In the adult group the similar analysis revealed operative vaginal delivery (OR = 2.44, CI 1.72-3.47, p < 0.001) and a birthweight≥90th percentile (OR = 2.23, CI 1.19-4.18, p = 0.012) to be independent risk factors for OASI. CONCLUSION: Adolescents have similar risk for OASI compared to adults but differ in risk factors leading to OASI. Head circumference ≥ 90th percentile was found to be associated with OASI in this age group.

Obstetric anal sphincter injury following previous vaginal delivery.

INTRODUCTION AND HYPOTHESIS: Obstetric anal sphincter injury (OASI) is a debilitating complication of vaginal delivery. The aim of this study was to identify risk factors for OASI in women with a previous vaginal delivery. We further attempted to detect specific risk factors for severe OASI in this subgroup. METHODS: We conducted a retrospective cohort study between 2003 and 2019. The study group included women who had a singleton, live, vertex, vaginal delivery at term and who also had at least one previous vaginal delivery. The control group included women with at least one previous vaginal delivery without OASI. General medical history, obstetric history, and ante-, intra- and post-partum data were collected and compared between groups. RESULTS: Following implementation of the inclusion criteria, 79,176 women were included. Allocation to study groups was according to OASI occurrence: 135 patients (0.2%) had a third- or fourth-degree perineal tear, while 79,041 patients (99.8%) had no such injury. Multivariate analysis revealed that one previous vaginal delivery, birthweight ≥ 3900 g (90th percentile), vacuum-assisted vaginal delivery and episiotomy were associated with increased risk of OASI. Comparison of more severe OASI (3C and 4th-degree) cases to the control group showed similar results with the addition of prolonged second stage and younger age to risk factors associated with severe OASI while episiotomy was no longer significant. CONCLUSION: In women with a previous vaginal delivery, one vs. two or more previous vaginal deliveries, increased birthweight, vacuum-assisted vaginal delivery and episiotomy are risk factors for OASI.