Risk of Preterm Birth Discovered for Women with Short Intervals Between Pregnancies

It turns out that women who have short intervals between pregnancies may be more likely to see a decrease in the length of following pregnancies. The findings reveal how having two pregnancies with a break of less than 18 months could impact future child bearing.

In order to learn a bit more about how a short interpregnancy interval (IPI) might impact women and future pregnancies, the researchers examined birth records from the Ohio Department of Health. In all, they looked at 454,716 live births from women with two or more pregnancies over a six year period. They then looked at the influence of inadequate birth spacing on the duration of the subsequent pregnancy.

So what did they find? It turns out that mothers with shorter IPIs were more likely to give birth prior to 39 weeks gestation when compared to women who had a longer time between pregnancies. In fact, following a short IPI of less than 12 months, about 53.3 percent of women had delivered before 39 weeks compared to 37.5 percent of women with an optimal IPI.

That's not all the researchers found, either. Women who had a shorter duration between pregnancies were also more likely to have a preterm birth before 37 week gestation.

"Short interpregnancy interval is a known risk factor for preterm birth; however, this new research shows that inadequate birth spaces is associated with shorter overall pregnancy duration," said Emily DeFranco, one of the researchers, in a news release. "This study has potential clinical impact on reducing the overall rate of preterm birth across the world through counseling women on the importance of adequate birth spacing, especially focusing on women known to be at inherently high risk for preterm birth."

The findings reveal the importance of educating women on optimal IPI. Inadequate birth space is associated with more adverse pregnancy outcomes, including preterm birth. Having at least 18 months or more between pregnancies can reduce the risk of these adverse outcomes, and leads to the likelihood of a safer pregnancy.

The findings are published in the journal BJOG: an International Journal of Obstetrics and Gynaecology.