In the last decade, the number of multiple pregnancies has increased globally, which medical professionals attribute to the widespread use of assisted reproductive technologies and the older age of mothers.
Previous studies, where researchers tracked women who gave birth to twins over several decades, did not show a higher long-term risk of cardiovascular diseases among them. However, specialists in obstetrics, gynecology, and reproductive sciences from the Robert Wood Johnson Medical School at Rutgers University (USA) noted that these findings diverge from the actual clinical experiences observed among patients with twins.
To investigate the issue, medical professionals examined data from a statistical database concerning 36 million women who gave birth in American hospitals between 2010 and 2020 and had no prior hospitalizations for vascular or heart diseases. For further analysis, the patients were divided into four groups, distinguishing between women with singleton and twin pregnancies, as well as those who had normal blood pressure during pregnancy and those who experienced hypertensive disorders.
In each group, the proportion of patients who were readmitted to the hospital within the first year after childbirth for any type of cardiovascular disease (CVD), including heart attack, heart failure, or stroke, was calculated.
The findings revealed that overall, the hospitalization rate for mothers of twins was 1105.4 per 100,000 births, which is one and a half times higher than that of women with a single child, at 734.1 per 100,000 births. Among mothers with normal blood pressure, those with twins were hospitalized due to CVD approximately twice as often as those who gave birth to one child.
The group with the highest hospitalization rates for heart diseases in the first year after delivery consisted of women with twins and hypertensive disorders during pregnancy. Their corresponding risk was found to be eight times higher than that of patients with a single child and blood pressure issues during pregnancy. For those who had one child and suffered from hypertension, the risk coefficient was 5.89.
Additionally, an analysis of mortality from all causes, including CVD, one year after childbirth revealed higher rates in the group of patients with singleton pregnancies and hypertension, compared to mothers of twins who also had blood pressure issues during pregnancy. According to medical experts, this may indicate reduced long-term risks for mothers of twins and the impact of additional negative variables on those who gave birth to one child.
In conclusion, the researchers urged their colleagues to take these identified risks into account when monitoring patients during pregnancy and after childbirth, as well as to provide more detailed information about them to women undergoing IVF and other similar procedures that increase the likelihood of multiple pregnancies. An article on this topic was published in the journal European Heart Journal.