This multicenter retrospective cohort study assesses the effect of high paternal DNA fragmentation on the well-being of the woman during pregnancy and the health of the newborn delivered. It was performed with clinical data from 488 couples who had a delivery of at least one newborn between January 2000 and March 2019 (243 used autologous oocytes and 245 utilized donated oocytes). Couples were categorized according to sperm DNA fragmentation (SDF) level as ≤15% or >15%, measured by TUNEL assay. Pregnancy, delivery, and neonatal outcomes were assessed. In singleton pregnancies from autologous cycles, a higher but non-significant incidence of pre-eclampsia, threatened preterm labor, and premature rupture of membranes was found in pregnant women from the >15%SDF group. Additionally, a higher proportion of children were born with low birth weight, although the difference was not statistically significant. After adjusting for potential confounders, these couples had lower odds of having a female neonate (AOR = 0.35 (0.1–0.9), p = 0.04). Regarding couples using donor’s oocytes, pregnancy and neonatal outcomes were comparable between groups, although the incidence of induced vaginal labor was significantly higher in the >15% SDF group (OR = 7.4 (1.2–46.7), p = 0.02). Adjusted analysis revealed no significant association of elevated SDF with adverse events. In multiple deliveries from cycles using both types of oocytes, the obstetric and neonatal outcomes were found to be similar between groups. In conclusion, the presence of an elevated SDF does not contribute to the occurrence of clinically relevant adverse maternal events during pregnancies, nor does it increase the risk of worse neonatal outcomes in newborns. Nevertheless, a higher SDF seems to be related to a higher ratio of male livebirths.

Background: Concomitant with delays in childbearing, concerns have been raised of whether advanced paternal age is associated with adverse reproductive outcomes, but the evidence is controversial in part due to the uncertain threshold in which to consider advanced paternal age and confounding maternal factors. This retrospective study aimed to evaluate the effect of paternal age on reproductive outcomes related to the pregnancy and perinatal health of the offspring. Methods: We retrospectively evaluated 16,268 cases of patients who underwent IVF or ICSI (using autologous sperm and donated oocytes, between January 2008 and March 2020, at Spanish IVIRMA clinics. Patients were divided based on paternal age at conception [≤30 (n = 204), 31–40 (n = 5752), and >40 years (n = 10,312)], and the differences in obstetrical and perinatal outcomes were analyzed by descriptive analysis, followed by univariate and multivariate analysis. Results: Fathers 31–40 and >40 years old were associated with lower odds of caesarean delivery [AOR 0.63 (95% CI, 0.44–0.90; p = 0.012) and AOR 0.61 (95% CI, 0.41–0.91; p = 0.017), respectively] and longer pregnancies [ARC 5.09 (95% CI, 2.39–7.79; p < 0.001) and ARC 4.54 (95% CI, 1.51–7.58; p = 0.003), respectively] with respect to fathers ≤30 years old. Furthermore, fathers aged 31–40 years old had lower odds of having a female infant (AOR, 0.70; 95% CI, 0.49–0.99; p = 0.045) than those ≤30. The rest of obstetrical and perinatal outcomes, which we deemed more medically-relevant as they were considered serious for health, were comparable between groups with our adjusted model. Conclusions: Despite this hopeful message to fathers of advanced paternal age, future studies should consider the short- and long-term outcomes of the offspring and try to better elucidate the associations of advanced paternal age with reproductive outcomes and the molecular mechanisms underlying the observed associations.

Background: In recent years, there has been an evident delay in childbearing and concerns have been raised about whether this increase in age affects reproductive outcomes. This study aimed to evaluate the effect of paternal age on obstetrical and perinatal outcomes in couples undergoing in vitro fertilization or intracytoplasmic sperm injection using autologous sperm and oocytes. Methods: This retrospective study evaluated obstetrical and perinatal outcomes from 14,125 couples that were arbitrarily divided into three groups according to paternal age at conception: ≤30 (n = 1164), 31–40 (n = 11,668) and >40 (n = 1293). Statistics consisted of a descriptive analysis followed by univariate and multivariate models, using the youngest age group as a reference. Results: The study showed significantly longer pregnancies for the fathers aged 31–40 compared to ≤30 years. However, there were no significant differences for the type of delivery, gestational diabetes, anaemia, hypertension, delivery threat, premature rupture of membranes, preterm birth, very preterm birth, and the neonate’s sex, weight, low birth weight, very low birth weight, length, cranial perimeter, Apgar score and neonatal intensive care unit admission. Conclusion: Despite our promising results for older fathers, as paternal age was not associated with clinically relevant obstetrical and perinatal outcomes, future well-designed studies are necessary as it has been associated with other important disorders.

Obesity is a multifactorial disease present worldwide and correlated with hormonal alterations that may cause a decrease in reproductive outcomes and seminal quality. However, the specific mechanisms involved are unknown. This led us to examine the relationship between paternal body mass index (BMI) and clinical reproductive outcomes by evaluating the cumulative live birth rates (CLBRs) per number of embryo transfers (ETs), embryos replaced (EmbRs), and oocytes used (OUs) in consecutive treatments until achieving the first newborn. A retrospective study was performed, and Kaplan–Meier survival curves were created to observe CLBRs with regard to the paternal BMI, adjusted by relevant confounders through Cox regression models. The participants were couples undergoing intracytoplasmic sperm injection (ICSI) and ET in Spanish IVIRMA clinics using autologous gametes. The cohort was subdivided based on paternal BMI: normal (18.5–24.99 kg/m²) (N), overweight (25–29.99 kg/m²) (OV), or obese (≥30 kg/m²) (OB) patients. A total of 4750 ICSI cycles were included, encompassing 49,485 mature oocytes, 23,963 blastocysts, and 3048 ETs. When calculating CLBRs based on the number of ETs carried out until live birth was achieved, no statistically significant differences were found (p = 0.72). After adjusting for maternal age and BMI, female infertility diagnosis, the use of preimplantation genetic testing, and the number of ETs, Cox regression showed that there were no statistically significant differences between the BMI groups (HR: 0.94 [95% CI: 0.7–1.2]; p = 0.59). When calculating CLBRs considering EmbRs, there was a similarity between the BMI groups (p = 0.57). However, there were no statistically significant differences in the adjusted Cox regression (HR: 0.93 [95% CI: 0.7–1.2]; p = 0.51). Finally, when calculating CLBRs considering OUs, the results were comparable among BMI subgroups (p = 0.75), and there were no statistically significant differences with adjusted Cox regression (HR: 0.95 [95% CI: 0.8–1.2]; p = 0.66). In conclusion, paternal BMI was not associated with clinical reproductive outcomes when considering the ETs, EmbRs, or OUs needed to reach the first liveborn (LB).