Mothers with history of stillbirth, miscarriage pose higher risk of CHD in offspring: JAMA

China: A new study found that offspring born to mothers who had a previous SA or stillbirth, especially multiple episodes, or who had pre-pregnancy type 2 diabetes were more likely to be diagnosed with congenital heart disease (CHD). The findings of the study were published in The Journal of American Medical Association (JAMA) on 10th November 2021.

CHD is the most common congenital anomaly, with a global prevalence ranging from 9 to 18 per 1000 live births in 2017, resulting in 2.6 million deaths globally. CHD etiology is complex, and epidemiological studies have suggested that a genetic or environmental cause can be identified in 20% to 30% of CHD cases.

A team of researchers led by Honglei Ji conducted this study with the objective to look at the links between maternal pregnancy loss and CHD in offspring, as well as the role of maternal type 2 diabetes. 

In this study maternal history of SA, with frequency ranging from one or two to three or more episodes, as well as a history of single and multiple stillbirths were assessed. Overall CHD was identified through hospital diagnosis. The hazard ratio (HR) of CHD was calculated using Cox proportional hazard regression. Diabetes was investigated as a potential confounder and effect modifier.

Researchers discovered that a maternal history of SA and stillbirth were associated with increased risks of CHD in offspring of 16% and 49%, respectively, in this population-based cohort study of offspring born between 1977 and 2016. There was a dose-response relationship with a higher risk of CHD after multiple episodes of maternal SA or stillbirth. The link was strengthened further by maternal type 2 diabetes during pregnancy, with the risks of CHD increasing by 66% and 74%, respectively, among those with a history of SA and stillbirth. It was also discovered that prenatal type 2 diabetes exacerbated the effects of a mother's history of SA and stillbirth on CHD.

In conclusion, the findings of this cohort study add to the growing body of evidence that children of mothers with a history of SA or stillbirth are more likely to be diagnosed with CHD. The risk increased as the mothers had more episodes of SA or stillbirth. Furthermore, children had a much higher risk of CHD if their mothers had type 2 diabetes during pregnancy. These findings may aid in the identification of high-risk groups for detailed, cost-effective fetal heart assessments that facilitate prenatal diagnosis or early diagnosis after birth in order to improve perioperative outcomes for children with certain types of CHD.

Reference:

Ji, H., Liang, H., Yu, Y., Wang, Z., Yuan, W., Qian, X., Mikkelsen, E. M., Laursen, A. S. D., Fang, G., Huang, G., Miao, M., & Li, J. (2021). Association of Maternal History of Spontaneous Abortion and Stillbirth With Risk of Congenital Heart Disease in Offspring of Women With vs Without Type 2 Diabetes. In JAMA Network Open (Vol. 4, Issue 11, p. e2133805). American Medical Association (AMA). https://doi.org/10.1001/jamanetworkopen.2021.33805