Women who are obese during pregnancy may die earlier or have an increased risk of heart problems later in life, according to a new study in the United Kingdom.
“What is surprising is that a measurement of obesity in pregnancy when women are young is a marker of risk for later cardiovascular disease and mortality,” said senior author Rebecca M. Reynolds of the Queen’s Medical Research Institute of the University of Edinburgh.
In a previous study, Reynolds and her coauthors also linked maternal obesity to increased risk of premature death among the women’s adult children.
It’s possible that being obese when a woman is relatively young - in this case, reproductive age – is a sign that her cardiovascular system is already under strain, the study team writes in Hypertension. Metabolism changes during pregnancy might add to that strain, they speculate.
As one in five women in the U.K. is obese, pregnancy could be a good time to identify and reduce obesity, the authors point out.
The researchers used maternity records from more than 18,000 women who gave birth to their first child between 1950 and 1976 in Scotland, and followed them for an average of 50 years by tracking deaths and causes of death in a Scottish database of death records.
They divided the women based on whether they were underweight, normal weight, overweight or obese at their first prenatal visit.
Women who were obese during pregnancy were about 30 percent more likely to have died during follow-up than those who were normal weight, even after accounting for factors like smoking, socioeconomic status and preeclampsia, a condition involving high blood pressure during pregnancy.
Overweight and obese mothers were 6 percent and 26 percent, respectively, more likely than normal weight mothers to be admitted to the hospital for a heart problem, like heart attack.
Women who did not have children were not included in the study, so it remains unknown whether an obese woman who has children has better or worse outcomes than one who does not, Reynolds told Reuters Health by email.
“We don't know whether pregnancy 'unmasks' problems earlier for women i.e. pregnancy acts as a 'stressor',” she said.
Likewise, they do not know if women who are obese during pregnancy may be unhealthier at other points in their lives as well, Reynolds said.
“We know that obesity is a risk factor for heart disease and early mortality and it is not surprising that obesity starting in the childbearing years would have repercussions for health later,” said Morgana Mongraw-Chaffin, a postdoctoral fellow in cardiovascular epidemiology at the University of California, San Diego.
“Obesity during pregnancy is associated with children being born large for gestational age and these children are more at risk for childhood obesity and diabetes later in life,” Mongraw-Chaffin, who was not part of the new study, told Reuters Health by email.
“Women who are planning pregnancy should aim for a healthy weight prior to conception,” Reynolds said.
“When women are pregnant they have a lot of contact with health care professionals including obstetricians and midwives,” she said. “This is a good opportunity to offer advice about a healthy lifestyle and healthy weight to prevent future adverse consequences for the women and their children.”