麻豆传媒

Increasing paternal age did not worsen pregnancy outcomes among couples undergoing in vitro fertilization (IVF), according to a retrospective study.

Compared with couples with younger paternal ages during IVF, those with advanced paternal ages (48 and older) did not experience lower live birth rates (adjusted OR [aOR] 1.07, 95% CI 0.80-1.44), reported Nahid Punjani, MD, MPH, of Weill Cornell Medicine in New York.

Advanced paternal age was also not associated with reduced implantation rates (aOR 1.00, 95% CI 0.78-1.29) or pregnancy rates (aOR 1.01, 95% CI 0.78-1.33), Punjani said during a virtual presentation at the American Society for Reproductive Medicine annual meeting.

In the initial analysis, implantation, clinical intrauterine pregnancy, and live birth rates decreased among women ≥37 years, as paternal age increased. Couples consisting of both an older woman and an older man had lower chances of implantation (OR 0.59, 95% CI 0.46-0.74), clinical intrauterine pregnancy (OR 0.55, 95% CI 0.43-0.71), and live birth (OR 0.54, 95% CI 0.41-0.71). After adjustment for continuous female age, none of these findings were significant. Advanced paternal age had no effect on any IVF outcomes in the younger women groups.

The researchers also found that couples with advanced paternal ages did not face higher rates of pregnancy loss.

"We demonstrate that once adjusting for advanced maternal age, advancing paternal age has no impact on pregnancy or neonatal outcomes," Punjani said. "Further work is required to understand the long-term effects on offspring in these cohorts," he added.

The number of fathers over age 40 in the U.S. has doubled since 1970, Punjani noted, with the mean age increasing from 27 to 40. While there are currently no paternal biological limitations for conception, has shown an effect of advancing paternal age on IVF outcomes.

Punjani's group aimed to determine the impact of advanced paternal age on fertility treatment outcomes, including live birth, implantation, clinical intrauterine pregnancy, and pregnancy loss rates. The researchers reviewed all first autologous IVF cycles at a high-volume single center from 2013 to 2019. They excluded cycles if donor sperm was used, or if transfer did not occur on day 3 or day 5.

Couples were split into six groups categorized by both maternal and paternal ages. Maternal age was categorized by women <37 years and those ≥37 years. There were three younger women groups with increasing paternal age, and three older women groups with increasing paternal age.

The researchers adjusted for female age, the use of surgically retrieved sperm, severely low sperm count, and developmental age at the time of transfer.

The study included 6,704 couples, 83% of whom used intracytoplasmic sperm injection. Compared with the younger women groups, older women were more likely to have a male partner with a higher sperm count, and were more likely to use fresh sperm rather than frozen sperm. The number of mature eggs, however, was higher in the younger women groups (approximately 11 vs 7).

The study is limited by its retrospective design and reliance on data from a single center, Punjani noted. Additionally, because this study took place in a high-volume fertility center, he said that it's possible that participants had expected worse outcomes, which may limit generalizability.

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