부산대학교 도서관

Background: Many studies have considered maternal age as a determinant factor for success in assisted reproductive technologies (ART), but the potential role of paternal age on neonatal outcomes has been overlooked. This study aimed to explore the association between paternal age and birthweight in frozen embryo transfer (FET) cycles. Methods: This retrospective study involved singleton live births born to women undergoing frozen embryo transfer from January 2013 to December 2017 at a tertiary care center in Shanghai, China. The paternal age was classified into four categories: ≤ 30, 31–35, 36–40, and ≥ 41 years. The group consisting of respondents with paternal age of 31–35 was set as the reference group. Singleton birthweight was the primary outcome measure. Z-scores were calculated according to gestational age and newborn gender on birthweight based on the national birthweight reference. Multivariable linear regression analysis was performed to reveal the relationship between paternal age and newborns' birthweight after considering several potential confounders. Results: Exactly 9765 women who fulfilled the inclusion criteria were enrolled. No significant difference was found on mean birthweight (P = 0.082) and gestation-adjusted Z-scores (P = 0.569) among paternal age categories. The reference group and the group with aged 36–40 years had the highest mean birthweight and Z-scores, respectively (3350.2 ± 467.8 g, 0.36 ± 1.00). A decline in mean birthweight with paternal age was observed, and the group over 40 years had the lowest value of 3309.4 ± 474.3 g, but the difference was not statistically significant. In multivariate analyses, the adjusted odds of very low birthweight (LBW), LBW, and high birthweight in the reference group did not significantly differ with the three other groups. After correcting several potential confounders, no significant correlation was observed between paternal age and neonatal birthweight (P = 0.289). Conclusion: Paternal age was not associated with mean birthweight and gestational age- and gender-adjusted birthweight (Z-scores) of singletons among women who became pregnant in FET cycles. Plain English summary: Currently, many couples delay childbearing until after the age of 40. The natural decline of fertility of elderly couples forces them to utilize assisted reproductive technology. Although males continuously produce sperm throughout their entire life, their sperm quality decreases, changes occur in reproductive hormones, the incidence of de novo mutations increases, and negative behavioral choices could cause a decline in males' fertility potential after the age of 40. Due to their age women may also face fertility issues that have an impact on pregnancy and childbirth. This study only included couples who had successfully given birth in frozen embryo transfer cycles. Considering that birthweight is an important indicator of neonatal health, we explored the association between paternal age and singleton birthweight. Our study found that paternal age is not associated with mean birthweight and gestational age- and gender-adjusted birthweight (Z-scores) of singletons in FET cycles, showing chances of successful pregnancy in couples over 40 years of age have improved. [ABSTRACT FROM AUTHOR]