New ESHRE findings: Paternal age and the risk of spontaneous miscarriage
The first systematic review and meta-analysis investigating the importance of paternal age has found that advanced paternal age beyond 40 years is significantly associated with an increased risk of spontaneous miscarriage when adjusted for maternal age, especially in the first trimester of pregnancy. Plenty of small individual studies had been carried out on this topic however by pooling the data in this meta-analysis study, statistical power was increased and therefore consolidated the conclusion that older fathers, independently of maternal age, do introduce a small but considerable risk for miscarriage in spontaneous and ART pregnancies.
It is common knowledge that since the 1970’s child bearing has been delayed and trends over the years have captured this steady rise. In the 1970’s couples were starting their families at 23, fast forward 50 years and we are in our 30’s. This delay in childbearing accounts for something as we know that as we age, the risk of miscarriage increases.
Advanced maternal age is known to impact female fertility and increase the risk of spontaneous miscarriage however now, this new research sheds some light on the importance of men’s ageing sperm and the genetic material required for embryo development. DNA integrity and the genetic make up of sperm is important as it provides 50% of the required genetic make-up for a new life. High levels of DNA fragmentation have been directly linked to recurrent miscarriage.
“Fathers between 40-44 years of age were 23% more likely to contribute to the incidence of spontaneous miscarriage before 20 weeks of gestation than their younger peers. Similarly, when the paternal age was over 45 years the risk for pregnancy loss before 20 weeks was increased by 43% and before 13 weeks by 74%.”
The Future
A new prospective case-control study (REMI III project) has commenced by the same researchers in order to assess the impact and predictive value of various paternal factors, including age and sperm DNA integrity, on recurrent pregnancy loss. The first results are expected later at the end of the year, with a follow up pending in 2025.