Irish women over 40 are three times as likely to miscarry than those in their 20s, it has been revealed.
The study by UCC researchers examined more than 50,000 expectant mothers over the 11-year period between 2005 to 2016.
During that time, the number attending maternity wards with early miscarriage sharply dropped by 19%.
The analysis found women over 40 are three times more likely to be hospitalised in the first 13 weeks of pregnancy than those under 25.
The authors of the paper, headed by Indra San Lazaro Campillo of the Pregnancy Loss Research Group at UCC’s Irish Centre for Fetal and Neonatal Translational Research, said the findings were “not surprising”.
The article said: “Advanced maternal age is one of the most studied and well-known factors associated with an increased risk of miscarriage.”
It also explained research shows more women in high-income countries are delaying getting pregnant.
It added: “A proportion of older women will have become pregnant following fertility treatment and this may also be associated with an increased risk of pregnancy loss.”
The study found women under 25 had a rate of miscarriage of 58 in 1,000 births.
Those between 25 and 29 had the lowest rate – 51 per 1000 – and women between 30 and 34 had a rate of 52 in 1,000.
The numbers increased significantly with age as women between 35 and 39 had a miscarriage rate of 74 in 1,000.
Figures rose sharply to 151 in every 1,000 pregancies in those over 40.
The study also found public patients had almost double the risk of being hospitalised with early miscarriage.
It also showed 1.2% of those who suffered an early miscarriage then required a blood transfusion compared to 0.6% for those with private health insurance cover.
The article added: “Previous studies have found an association between higher risk of pregnancy loss and economic disparities.
“A controversial but plausible factor that might have influenced this result is the delay in time taken to provide care to public patients compared to private patients.”
The study analysed the records of 50,538 hospitalisations in all acute maternity hospitals using the Hospital In-Patient Enquiry database.
