WHITE PLAINS, N.Y., Aug. 18, 2015 - Shorter mothers have shorter pregnancies, smaller babies, and higher risk for a preterm birth. New research has found that a mother's height directly influences her risk for preterm birth. 
 
 Investigators at the March of Dimes Prematurity Research Center Ohio Collaborative looked at 3,485 Nordic women and their babies, and found that maternal height, which is determined by genetic factors, helped shape the fetal environment, influencing the length of pregnancy and frequency of prematurity. In contrast, birth length and birth weight are mainly influenced by transmitted genes. Preterm birth is the number one killer of newborns in the United States and serious gaps exist between racial and ethnic groups. 
 
 More than 450,000 babies are born too soon in the U.S. and the national preterm birth rate is worse than many other high-resource countries, the March of Dimes says. Worldwide, 15 million babies are born preterm, and more than one million die due to complications of an early birth. Babies who survive an early birth face serious and lifelong health problems, including breathing problems, jaundice, vision loss, cerebral palsy and intellectual delays. 
 
 "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 Leigh Simpson, MD, March of Dimes senior vice president for Research and Global Programs. 
 
 "The innovative, team-based model of our prematurity research centers is critical to understanding the unknown causes or preterm birth. This new finding adds one small piece toward solving the much larger puzzle of preterm birth," says Dr. Jennifer L. Howse, president of the March of Dimes. 
 
 The March of Dimes is raising $75 million to support its five prematurity research centers. These unique, transdisciplinary centers bring together the brightest minds from many diverse disciplines -- geneticists, molecular biologists, epidemiologists, engineers, computer scientists, and others -- to work together to find answers to prevent premature birth. In addition to the Ohio Collaborative, the March of Dimes has established research centers at Stanford University School of Medicine in California, at the University of Pennsylvania, at Washington University in St. Louis, and at the University of Chicago, Northwestern University and Duke University. 
 
 "Our finding shows that a mother's height has a direct impact on how long her pregnancy lasts," said Louis Muglia, MD, PhD, the primary investigator of the Ohio Collaborative, and co-director of the Perinatal Institute at Cincinnati Children's Hospital Medical Center. "The explanation for why this happens is unclear but could depend not only on unknown genes but also on woman's lifetime of nutrition and her environment." 
 
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 The research paper, "Assessing the Causal Relationship of Maternal Height on Birth Size and Gestational Age at Birth: A Mendelian Randomization Analysis," was published online Aug. 18 by PLoS Medicine. 
 
 The March of Dimes works to improve the health of babies by preventing birth defects, premature birth and infant mortality. The March of Dimes is the leading nonprofit organization for pregnancy and baby health. For the latest resources and information, visit marchofdimes.org or nacersano.org. Visit prematurityresearch.org for more information about the research centers. Find us on Facebook and Twitter. ||||| The obesity epidemic is unrelenting, especially among women. A study released this week found that more women than men are now affected by the disease, while the reverse was true just two years ago. The condition is associated with a wide variety of health risks, from chronic diseases to reproductive problems — and in a new study published June 7 in PLOS Medicine, researchers from the Karolinska Institutet in Sweden found that gaining weight between pregnancies further complicates mothers’ and infants’ health. 
 
 Already, research suggests that women who are overweight and obese during pregnancy face greater risk of certain complications, including gestational diabetes and preeclampsia. Infants born to obese women, on the other hand, sometimes score lower on the Apgar test, which is given no more than five minutes after babies are born to determine if they have breathing or heart trouble. While low scores can’t predict the future health of a child, they are commonly caused by asphyxia, a slippery slope that leads to additional adverse outcomes. 
 
 Maternal obesity increases newborns' risk for adverse outcomes. Pixabay 
 
 The researchers were interested to learn more about the ways a woman’s body mass index (BMI) could influence these complications and outcomes. They specifically looked at women’s BMI between their first and second pregnancies using data from the Swedish Medical Birth Register and any asphyxia-related outcomes: neonatal seizures and meconium aspiration syndrome, a severe breathing condition. Researchers also analyzed demographic information for more than 500,000 mothers who had their first and second live births between January, 1992, and December, 2012, including Apgar test scores and mothers’ and infants’ measurements and proportions. 
 
 Essentially, lead author Martina Persson and her team calculated weight gain and risks in two ways: one, they looked at low scores and asphyxia-related morbidities; and two, they looked at risks of these outcomes per every unit increase in a mother’s BMI. 
 
 The results showed an increased risk for all adverse outcomes in infants whose mothers’ BMIs increased by 2 units or more between pregnancies; 6 pounds is about one BMI unit for a woman of average height. These risks were more pronounced in women who started their first pregnancy at normal weight — a BMI of less than 25 — and then gained weight. 
 
 On the other hand, the increase in risk was less pronounced in women who were overweight and obese during early pregnancy. Persson and her colleagues speculate this may reflect the ways metabolism adapts to increased fat mass over time, meaning overweight women in early pregnancy might accumulate less fat in pregnancy than underweight and normal weight women. 
 
 To the researchers’ knowledge, this is the first time a study has assessed these particular risks and how they are influenced by change in weight over time. 
 
 It’s a strong study in that it analyzes a large number of births, exposures, and outcomes; however, the authors did not have information on gestational weight gain and do not know when exactly women gained weight between their first and second pregnancies. The distribution of fat may differ if weight is gained during or after pregnancy, they said. 
 
 Even so, they believe the findings are significant and could influence public health initiatives. 
 
 “Given the high prevalence of maternal overweight and the possible long-term consequences of birth asphyxia, our results have substantial public health relevance, as even modest weight increases in normal weight women may impact offspring outcomes on a population level,” the researchers concluded. Encouraging women to normalize BMI before pregnancy and to avoid weight gain between pregnancies, they said, would likely help improve infant health. 
 
 Source: Persson M, Johansson S, Cnattingius S. Interpregnancy Weight Change and Risks of Severe Birth-Asphyxia-Related Outcomes in Singleton Infants Born at Term: A Nationwide Swedish Cohort Study. PLOS Medicine. 2016.
– The height and weight of a newborn baby is largely governed by his or her own genes, but it's the height of the mother that's giving researchers a telltale sign, reports the Telegraph. Specifically, shorter women have shorter pregnancies and thus more premature babies, report investigators at the March of Dimes Prematurity Research Center Ohio Collaborative in the journal PLOS Medicine. The team analyzed 3,485 Nordic women and their babies, and found that a woman's height actually shapes the fetal environment, thereby influencing the length of her pregnancy. This has broad health implications around the world, where 15 million babies are born prematurely every year and more than 1 million of them die due to complications of early birth—which include breathing problems, vision loss, and intellectual delays, report researchers in a press release. "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," one researcher says. (Premature birth is now the world's top killer of children under 5.)