Short Mom, Short Pregnancy

Pregnancy length and birth weight may be influenced by mother's height

Moms-to-be who typically occupy the front row in group photos may have different pregnancy outcomes than taller women.

A new study found that shorter mothers tended to have shorter pregnancies. They also had smaller babies and an increased risk for early delivery.

"Our finding shows that a mother's height has a direct impact on how long her pregnancy lasts," said lead study author Louis Muglia, MD, PhD, co-director of the Perinatal Institute at Cincinnati Children's Hospital Medical Center, in a press release. "The explanation for why this happens is unclear but could depend not only on unknown genes but also on a woman's lifetime of nutrition and her environment."

Dr. Muglia and colleagues from the March of Dimes Prematurity Research Center Ohio Collaborative analyzed data on 3,485 Nordic women and their babies.

They found that women’s height may influence the length of pregnancy. Women who were shorter were more likely to deliver early.

The March of Dimes reports that 450,000 babies are born too early in the US each year. Babies born early have a higher risk of breathing problems, vision loss, cerebral palsy and intellectual delays.

A mother’s height is often genetically determined. The baby’s birth length and weight are likely influenced by genes the parents transmit to the baby, Dr. Muglia and team said.

"A major goal of the nationwide network of March of Dimes prematurity research centers is identifying genes that govern fetal growth and length of pregnancy. That a woman's height influences gestational length, independent of the genes she passes on that determine fetal size, is a major finding by our research networks, and the first of what we expect to be many genetic contributions," said Joe L. Simpson, MD, March of Dimes senior vice president for Research and Global Programs, in a press release.

This study was published in the August issue of PLOS Medicine.

This research was funded by the March of Dimes, National Institutes of Health, several private foundations and hospitals, Norwegian Research Council, Swedish Medical Society, Swedish Government Grants to Researchers in the Public Health Service, European Community’s Seventh Framework Programme, ENGAGE Consortium, European Research Council and University of Bergen.

Dr. Muglia and team disclosed no conflicts of interest.