A study published on June 6 in JAMA Pediatrics reveals that staying a week longer in the womb increases a baby’s intelligence. University of Florida researchers find that babies born at 41 weeks are more likely to be considered as gifted and get higher test scores than babies born at 40 weeks’ gestation, but their intelligence comes at a price.

While the study says that longer gestation increases cognitive ability, it also increases the risk of babies having physical disabilities. These suggest that 40 weeks is still the safest time for babies to be delivered in uncomplicated pregnancies.

The researchers linked 1994 and 2002 births in Florida with public school records from 1998 to 2013. They believe that increased intelligence stems from the extra week of uninterrupted brain maturation.


Newborn crying. Credit: Evan-Amos

Babies born at the 41st week of gestation were 2.8 percent more likely to be classified and 3.1 percent less likely to have poor cognitive assessments, scoring 10 more points on each section of SAT. On the other hand, these late-term babies were 2.1 percent more likely to suffer from physical disabilities, which include speech problems, sensory disorders, and bone disorders, which result to more hospitalization.

The babies that greatly benefited from staying one more week in the womb were the children of women who did not complete high school. The late-term babies of women with low level of education were 7.6 percent more likely to be gifted and 4.2 percent less likely to experience cognitive problems. Still, these babies are 5.1 percent more likely to suffer from physical disabilities than the full-term babies of women with low education levels.

Despite the other factors that could have played a role in the results, the researchers claim that their study established the clear relationship between longer gestation and better academic performance. The team asserts that the findings are not intended to encourage women to intentionally lengthen their pregnancy.