Study finds new link between miscarriage risk and maternal genes

TARTU, Estonia — Occurring in roughly 15 percent of clinical pregnancies, miscarriage is considered the most common complications an expecting mother can face. Now, a new study reports newly discovered connections between maternal genes and miscarriage risk.

Researchers from the Estonian Genome Center of the University of Tartu in Estonia conducted the study.

Physicians have been aware that miscarriage risk increases the older a woman becomes for quite some time. The reasons behind up to two-thirds of miscarriages however, are still unclear.

When it comes to the role of genes in determining a woman’s risk of miscarriage, earlier studies had found a loose connection of sorts between single maternal genetic variants and repeating miscarriages. However, those prior projects usually only included a small number of participants and ultimately yielded inconclusive results.

“Our study involved a large number of women whose gene variants were examined throughout the genome to find risk factors for sporadic or consecutive miscarriages,” explains first study author Triin Laisk, a Senior Research Fellow at the Estonian Genome Center, in a media release.

Which conditions can contribute to a miscarriage?

This new work performed in Europe shows that miscarriages are at least partially driven by genetic variations possibly caused by placental biology. Several seemingly unrelated health outcomes such as irritable bowel syndrome, depression, and asthma show a connection to miscarriages. Factors like smoking, general mental health, and overall well-being also seem to have a link in some way to miscarriages.

“Although previous studies have shown that miscarriage increases the risk of depression and cardiovascular diseases, the underlying reasons are unknown. However, genetic research will help us better understand what could be behind such associations,” Laisk says.

While this work only focused on the influence of maternal genes, study authors want to see more research in the future accounting for both paternal and fetal genomes.

“Although this study of maternal genetic variation shed some light on the causes of miscarriage, further research is definitely needed. In the future, we could know more about the biology behind a successful pregnancy and also about the long-term impact of miscarriage on overall health,” Laisk comments.

This study is actually just the starting point for a new international project studying these topics for years to come. For this initial round of research, the Estonian team gathered data on 420,000 women living all over the world.

“The results of this study illustrate the utility of large-scale biobank data for understanding this pregnancy complication,” Laisk concludes.

The study is published in Nature Communications.