Maternal size and weight gain before and during pregnancy are associated with adiposity and cardio-metabolic risk factors in adult offspring, according to a paper by Israeli and US researchers online in Circulation.
"Whether this predicts even worse outcomes for the next generation, given the rising trends in obesity, is unknown, yet the possibility is concerning," lead author Dr Hagit Hochner told Reuters Health by email.
Dr Hochner of Hebrew University-Hadassah Medical Centre in Jerusalem and colleagues studied 1400 young adults born in that city who had reached the age of 32 years.
They used data from that birth cohort to look for associations of maternal pre-pregnancy body mass index (mppBMI) and gestational weight gain with a range of cardio-metabolic risk factors in the now-adult offspring.
Gestational weight linked with child adiposity
Independently of gestational weight gain and confounders, greater mppBMI was significantly associated with higher offspring BMI, waist circumference, systolic and diastolic blood pressures, and insulin and triglyceride levels and with lower levels of high-density lipoprotein cholesterol (HDL).
Adults whose mothers were in the upper quartile of mppBMI (24.6 or more) they had a mean BMI that was almost five points higher than the mean BMI in adults whose mothers' mppBMI was 21 or less. Furthermore, their waist circumference was 8.4 cm greater, their triglycerides were 1.4mg/dL higher, and their HDL was 3.8mg/dL lower.
Gestational weight gain was also positively associated with offspring adiposity. Compared to offspring of mothers who gained less than 9 kg, adults whose mothers gained more than 14 kg had a BMI that was 1.6 points higher and a waist circumference that was 2.4 cm greater.
The findings may "have implications for risk-reduction interventions," Dr Hochner said. "Prevention of overweight and obesity among individuals exposed to an early obesity-promoting environment may decrease subsequent cardio-metabolic risks related to this early exposure. Clinical trials are warranted to explore this possibility."
Moderate pregnancy weight reduces obesity risk
Current US Institute of Medicine guidelines suggest that women with a normal weight for their height (BMI of 18.5 to 24.9) should gain 11 to 15kg during pregnancy. Overweight women (BMI of 25 to 29.9) should gain 6to 11.5kg. Obese women (BMI over 30) should limit their gain to 5 to 9kg.
Dr Matthew W. Gillman, who wrote an editorial that was published with Dr Hochner's paper, told Reuters Health by email, "Several ongoing randomised controlled trials are addressing the question, 'How can women avoid excessive gestational weight gain?'"
Dr Gillman, of Harvard Medical School and Harvard Pilgrim Health Care Institute in Boston, added "It will be crucial to follow up the children (to) determine if, as observational studies suggest, moderating weight gain during pregnancy reduces their risk for obesity and cardiovascular consequences."
"Future studies," he added, "will benefit by looking more deeply into the maternal and foetal components of weight gain, with the goal of more individualised approaches to the health of pregnant women and their children."
(David Douglas, Reuters Health, March 2012)