Spontaneous preterm delivery linked to higher risk of cardiovascular disease

by Bruce Sylvester: Compared to women who deliver at full-term, women with a history of spontaneous preterm delivery appear to have a doubled risk of developing heart disease, stroke and other cardiovascular diseases, according to findings published on Feb. 10, 2015 in the European Journal of Preventive Cardiology.

The findings come from a new meta-analysis of ten “high quality” cohort studies from five European countries (Denmark, Finland, Norway, Scotland, Sweden).

As background, the authors noted that, preterm delivery is defined as delivery before 37 weeks. Approximately one-third of such early deliveries are medically explicable. A precise explanation for the remaining spontaneous preterm deliveries, “remains unknown in many cases,” said the investigators.

Sample sizes of each study included in the meat-analysis ranged from 3,706 to 923,686, with follow-up of 12 to 35 years.

All of the studies were observational. The researchers in each study calculated the association between spontaneous preterm delivery and fatal or non-fatal ischemic heart disease, stroke or overall CVD.

In the meta-analysis, the investigators pooled and analyzed the data from the 10 studies.

They found that, compared to normal delivery, spontaneous preterm delivery was associated with an increased risk of fatal and non-fatal ischemic heart disease of 38% (HR/hazard ratio 1.38), an increased risk of fatal and non-fatal stroke of 71% (HR 1.71) and a doubled risk of overall fatal and non-fatal cardiovascular disease (HR 2.01).

Lead investigator, Karst Heida, MD, of the Department of Obstetrics at the University Medical Center, Utrecht, the Netherlands, noted that CVD risk factors like hypertension, high cholesterol, type 2  diabetes and thrombosis, often appear in women when they have a spontaneous preterm delivery.

The authors emphasized that the results from meta-analysis provides a quantitative estimate of risk, but no explanation of the risk.

Heida added that there is not yet enough evidence to include spontaneous preterm delivery in the accepted cardiovascular risk charts or in the standard prevention guidelines. But he noted that a history of spontaneous preterm delivery may identify a woman who is at an increased risk of CVD and that such a woman, “should be encouraged to optimise modifiable risk factors to reduce their risk of future CVD.”