Rise in abdominal birth defect among newborns

Incidence of gastroschisis among newborns appears to be on the rise, with the proportion of babies born with the rare defect almost doubling since 1995, new research shows.

Researchers reviewed the prevalence of the defects among millions of live births during an 11-year-period in the United States, using data from the National Birth Defects Prevention Network.

Though the study authors were unable to substantiate why the rate of the birth defect appears to be increasing,  there is evidence to suggest that the defect is more likely to be found in the children of teen mothers. Additionally, a mother’s contact with specific chemicals may be linked to the defect, though this is not definitive.

Children born with the defect require immediate surgery and while most survive, infants with the defect can develop problems with growth and development.

For the study, researchers evaluated 4713 cases of the disorder that were detected in 15 states from 1995 to 2005. Though the disorder is rather rare, during the study period, the number of cases rose from 2.3 out of every 10,000 live births in 1995 to 4.4 out of every 10,000 live births by 2005.

Age appears to play a role, as the rise in gastroschisis mostly impacted mothers younger than age 25, especially those under 20 years; conversely, women who had babies in their 30s did not see an increased risk of having babies with such a defect.

Study authors noted that mothers who had babies in their early 20s had a 5.8% increase each year of delivering a child with gastroschisis. For these mothers in particular, the gastroschisis rate jumped from 4 of every 10,000 babies in 1995 to 7 in 10,000 babies in 2005.  There was a 6.8% annual increase in the proportion of babies with gastroschisis born to teen mothers.

For mothers under age 20, in 1995 the rate of babies born to them with gastroschisis was 8 per every 10,000; in 2005, the number skyrocketed to 15 out of every 10,000 babies.

Mothers who were non-Hispanic black had the lowest risk of a gastroschisis-affected pregnancy (prevalence ratio 0.42, 95% confidence interval [CI] 0.37-0.48). Hispanic mothers followed (prevalence ratio 0.86, 95% CI 0.81-0.92) and non-hispanic white mother had even bigger risks. Asian and Native American saw no change in the number of gastroschisis cases during the study period. The study did not find any significant variation in prevalence of gastroschisis in either newborn sex.

Researchers do not yet have conclusive evidence as to what is causing the numbers to climb.

The lead author, Russell Kirby, a professor at the University of South Florida, suggests that nutrition may play a role in the increase, specifically the impact of certain vitamins and minerals on fetal growth. But current research does not yet verify such a link.

Currently, researchers are looking at the rates of gastroschisis since 2005.

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