"Long before it's in the papers"
January 27, 2015


Mom’s obesity may affect unborn child’s brain

Feb. 11, 2013
Courtesy of the Society for Maternal-Fetal Medicine
and World Science staff

Obes­ity in a preg­nant moth­er may lead to ab­nor­mal brain de­vel­op­ment in the fe­tus, sci­en­tists are warn­ing, based on a find­ing of ab­nor­mal pat­terns of ge­net­ic ac­ti­vity in such fe­tuses.

Al­though the im­plica­t­ions are un­clear, sci­en­tists called the find­ings a po­ten­tially ma­jor con­cern, giv­en that an es­ti­mat­ed one in three U.S. wom­en are obese at con­cep­tion. Re­search­ers from Tufts Med­i­cal Cen­ter in Bos­ton plan to pre­s­ent the find­ings on Feb. 15 at the So­ci­e­ty for Maternal-Fetal Medicine’s an­nu­al meet­ing in San Fran­cis­co.

“Women won’t be sur­prised to hear be­ing obese while preg­nant can lead to obes­ity in the child,” said An­drea Ed­low, lead au­thor of the stu­dy. “But what might sur­prise them is the po­ten­tial ef­fect it has on the brain de­vel­op­ment of their un­born child.”

The study ex­am­ined the fe­tal de­vel­op­ment of 16 preg­nant wom­en, eight obese and eight lean. As early as the sec­ond tri­mes­ter, obese wom­en’s fe­tuses were found to have dif­fer­ent pat­terns of gene ac­ti­vity, sug­ges­tive of ab­nor­mal brain de­vel­op­ment.

Dur­ing gesta­t­ion, fe­tuses go through apop­to­sis—a nor­mal pro­cess of pro­grammed “sui­cide” by cer­tain brain cells. This con­sti­tutes a sort of prun­ing, a clear­ing out out space for new growth, said Di­ana Bianchi, sen­ior au­thor of the study and ex­ec­u­tive di­rec­tor of the Moth­er In­fant Re­search In­sti­tute at Tufts.

Fe­tus­es of obese wom­en had ge­net­ic ac­ti­vity in­di­cat­ing de­creased apop­to­sis, an im­por­tant part of nor­mal fe­tal brain de­vel­op­ment, she ex­plained. It’s un­clear what ef­fect this will ul­ti­mately have on the de­vel­oped brain, she added, but she said ma­ter­nal obes­ity is a rap­idly grow­ing prob­lem in the Un­ited States and has been as­so­ci­at­ed with in­creased rates of au­tism and al­tered ap­pe­tite regula­t­ion.

Bianchi and Ed­low say their next step will be to use lab­o­r­a­to­ry mice to fur­ther study the obs­erved ge­net­ic dif­fer­ences.

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Obesity in a pregnant mother may lead to abnormal brain development in the fetus, scientists are warning, based on a finding of abnormal patterns of genetic activity in such fetuses. Although the implications are unclear, scientists called the findings a potentially major concern, given that an estimated one in three U.S. women are obese at conception. Researchers from Tufts Medical Center in Boston plan to present the findings on Feb. 15 at the Society for Maternal-Fetal Medicine’s annual meeting in San Francisco. “Women won’t be surprised to hear being obese while pregnant can lead to obesity in the child,” said Andrea Edlow, lead author of the study. “But what might surprise them is the potential effect it has on the brain development of their unborn child.” The study examined the fetal development of 16 pregnant women, eight obese and eight lean. As early as the second trimester, obese women’s fetuses were found to have different patterns of gene activity, suggestive of abnormal brain development. During gestation, fetuses go through apoptosis—a normal process of programmed “suicide” by certain brain cells. This constitutes a sort of pruning, a clearing out out space for new growth, said Diana Bianchi, senior author of the study and executive director of the Mother Infant Research Institute at Tufts. Fetuses of obese women had genetic activity indicating decreased apoptosis, an important part of normal fetal brain development, she explained. It’s unclear what effect this will ultimately have on the developed brain, she added, but she said maternal obesity is a rapidly growing problem in the United States and has been associated with increased rates of autism and altered appetite regulation. Bianchi and Edlow say their next step will be to use laboratory mice to study the genetic differences in more detail.