Posted: Aug 15, 2013 12:05 AM by MICHELLE CASTILLO - CBS News
A mother's obesity may not only harm her health: It may cut the life of her children short.
Children of pregnant mothers who were overweight or obese were significantly more likely to die before the age of 55 than those born to normal-weight moms, a Scottish study reveals.
"This study highlights the importance of weight management in mothers and their offspring," author Dr. Sohinee Bhattacharya, a lecturer at the University of Aberdeen in Scotland, said to the Telegraph. "We need to find out how to help young women and their children control their weight better so that chronic disease risk is not transmitted from generation to generation."
Researchers from the University of Edinburgh looked at 28,540 mothers and 37,709 of their children. All the kids were born in 1950 and later, and were aged 34 to 61 by 2011.
During a prenatal checkup, the mothers' weights and heights were recorded, and their body mass index (BMI) -- a ratio of height and weight -- was recorded. About 21 percent of the mothers in the study were classified as overweight (which meant they had a BMI between 25 and 29.9), and 4 percent were considered obese (BMI of 30 or over).
During the study, 6,551 of the children died before the age of 55. The leading causes of death were heart disease and cancer.
Children whose mothers were obese at birth had a 35 percent higher chance of dying by 2011 than those who were born to normal-weight mothers. Having an overweight mother increased the chance of an early death by 11 percent.
In addition, offspring of obese mothers had a 29 percent higher chance of being admitted to the hospital because of a heart problem. Overall, only 8 percent of the children had been admitted due to that reason.
The study appeared in BMJ on Aug. 13.
The authors believe that many factors may have contributed to the increased death risks in offspring of obese moms. Their genes may be more predisposed to earlier deaths, or their mother's poor eating habits may have influenced their post-natal lives.
In an accompanying editorial, Pam Factor-Litvak, associate professor of epidemiology at Columbia University in New York, wrote that weight issues for women of childbearing age has been an issue that has grown over the last two decades.
Factor-Litvak pointed out that being overweight or obese while pregnant has been connected to increased rates of pre-eclampsia (high blood pressure and large quantities of protein in the urine of pregnant women), gestational diabetes and death. Babies are also at a higher risk of being larger than average at birth and also have an increased chance of being obese later in life.
While Factor-Litvak said the study lacked information on the early environment for newborns and how much of a role parental obesity played on the weight of the child, she said that if the study's findings were true, it shows the importance of weight control before and during pregnancy. Not only should women continue to exercise during pregnancy, they should make lifestyle changes long before they decide to have children.
The Institute of Medicine recommends that women who have a normal weight during pregnancy gain 25 to 35 pounds during gestation. Underweight women should gain 28 to 40 pounds, and overweight women should gain 15 to 25 pounds. Obese women should only gain 11 to 20 pounds.
"The results of studies of maternal obesity and offspring outcomes suggest that interventions should begin before pregnancy," she wrote.
Shinga Feresu, an associate professor at Indiana University School of Public Health, added to HealthDay that health conditions like diabetes, kidney disease and high blood pressure could also have influenced the results. The researchers did not collect data on these from either the mother or child.
However, she reached the same conclusion as Factor-Litvak.
"Women who are obese need to reduce their weight to a healthy level before they become pregnant," Feresu concluded. "They will have a much healthier baby, with reduced risk of long-term disease and premature death."
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