The chance of having a premature baby is linked to the length of time between pregnancies in Latina women, according to a new study.
Research findings by a University of California San Francisco team show that Latina women with short interpregnancy intervals--18 months or less between the delivery of one infant and the following conception-- are at greater risk of premature birth than white women.
Elena Fuentes-Afflick, MD, UCSF assistant professor of pediatrics who treats patients at San Francisco General Hospital Medical Center, presented the study results today (Monday, May 3) in San Francisco at the annual meeting of the Pediatric Academic Societies.
The study is among the first to look specifically at the relationship between interpregnancy interval and prematurity in Latina women, according to Fuentes-Afflick.
"The strong association between these two factors in this ethnic group was a surprise, but it does present a clear recommendation. To insure the optimum health of the baby, Latina women should wait 18 months or longer between the birth of one child and conception of another baby," she said.
The study was based on 1991 birth information from the database of the U.S. National Center for Health Statistics. Data for a group of 150,000 Latina women of Mexican-origin was compared to a corresponding group of white women. Women ranged in age from 11 to 49 years.
The researchers looked at three classifications of a short interpregnancy interval: extremely short (under six months); very short, (6-11 months); and moderately short (12-17 months). An intermediate interpregnancy interval was defined as 24-29 months.
Study findings showed:
- Among Latinas, women with a short interval--of any length--were much more likely to give birth to a very premature (23-33 weeks) or moderately premature (33-37 weeks) baby than women with an intermediate interval. (A full-term baby is born at 38-42 weeks.)
- Latina women were twice as likely as white women to have an extremely short interval.
- Both Latina and white women in the short interval classifications were younger, less educated, and had less prenatal care than their counterparts who had intermediate interpregnancy intervals.
- There was no association between short intervals and premature birth among white women.
"As medical researchers looking at this subject, we need to conduct additional studies to determine the effects of behavior and/or biology on the outcomes and how we can turn them around," said Fuentes-Afflick. "We think it may be more behavioral and if so, the good news is that behavior can be changed." Study co-investigator was Nancy Hessol, MSPH, an epidemiologist in the UCSF Department of Medicine.
The research was supported by a grant from UC Mexus, a University of California research unit that focuses on U.S.-Mexico issues and people of Mexican descent.