Premature birth increases the risk of complications and health problems for babies. Now a new study published in the European Journal of Preventive Cardiology finds that a history of spontaneous preterm delivery may double the risk of heart disease, stroke, and other cardiovascular diseases (CVD) among women. Furthermore, premature birth appears “almost equally strong” ” as raised blood pressure, elevated lipid levels, overweight, smoking, and diabetes mellitus and an independent risk factor for CVD.
For the study, researchers performed a meta-analysis of ten large pregnancy cohort studies with sample sizes ranging from 3,706 to 923,686 women from five European countries (Denmark, Finland, Norway, Scotland, Sweden) and follow-up periods ranging from 12 to 35 years. Each study used a cohort design that assessed the association between spontaneous preterm birth and fatal or non-fatal ischaemic heart disease, stroke, or overall CVD.
Analysis of the data revealed that spontaneous preterm delivery increased the risk of fatal and non-fatal ischaemic heart disease by 38 percent and the risk of fatal and non-fatal stroke by 71 percent. Premature birth also more than doubled the risk of overall fatal and non-fatal cardiovascular disease.
Despite heterogeneity among the individual study results, the increased risks for women with a history of premature birth remained consistent when compared with women who gave birth full term.
Defined as delivery before 37 weeks of gestation, premature birth remains one of the most serious obstetric complications, affecting 12 to 13 percent of pregnancies in the United States and 5 to 11 percent in Europe. Approximately 15 million pregnancies annually end in premature birth worldwide, and more than one million newborn deaths occur as a result of complications of prematurity.
Approximately one-third of premature births in the United States and Europe occur for medical reasons such as preeclampsia and fetal growth restrictions. The remaining two-thirds occur spontaneously for reasons largely unknown.
The researchers in the present study note that classic CVD risk factors such as hypertension, high cholesterol, type 2 diabetes, and thrombosis often occur in women after spontaneous premature birth and may likely play a role in prematurity.
Comments lead author, Dr. Karst Y. Heida, a gynecology resident at the University Medical Center Utrecht:
“I don’t want to scare women who have a premature baby. But it’s important that we are aware of women who are at increased risk. We’re not saying that if you have a premature baby it means you’re going to have a cardiac event.”
Women who give birth prematurely should additionally “be encouraged to optimise modifiable risk factors to reduce their risk of future CVD.”
Adds Dr. Heida, “The pathways leading to the increased risk of developing CVD are not clear and there may be overlap with the different pregnancy complications.”
Another recent study found that fetal sex differences may partially account for premature birth, with women pregnant with boys at a higher risk of preterm delivery.
Impact of fetal gender on the risk of preterm birth: http://www.ajog.org/article/S0002-9378%2814%2901181-8/abstract
Premature delivery tied to heart risks in mother: http://well.blogs.nytimes.com/2015/02/11/premature-delivery-tied-to-heart-risks-in-mother/?_r=0
Women with a pregnancy history of spontaneous preterm delivery at higher risk of CVD: http://www.medicalnewstoday.com/releases/289201.php
Women with a pregnancy history of spontaneous preterm delivery found at higher risk of cardiovascular diseases: http://www.escardio.org/about/press/press-releases/pr-15/Pages/women-pregnancy-preterm-delivery-risk-cvd.aspx?hit=dontmiss
Premature Infant with CPAP: https://commons.wikimedia.org/wiki/File:Premature_infant_CPAP.jpg