Heart Concerns Linked to Premature Delivery

Factors that affect a woman's reproductive health can also have an effect on her heart, new research shows.

The findings of the two studies were presented at a recent American Heart Association meeting.

Giving birth prematurely or delivering a small-for-gestational-age baby is associated with a later risk of cardiovascular disease in the mother.

A third study found that when women's ovaries were removed and the estrogen was not replaced through hormone therapy, a woman's overall risk of dying increased, as did her risk of dying of heart disease or stroke.

The first study looked for associations between gestational size, the timing of the birth, and the risk of cardiovascular disease in more than one million Swedish women who had given birth to their first baby after 1973. Only women who carried one baby during pregnancy were included in the analysis.

Effects Seen Later in Life

The researchers followed up with the women for an average of 16 years, but some for as long as 33 years.

They found that women who had delivered a small-for-gestational-age baby or a preterm baby had a higher risk of cardiovascular disease; women who had delivered both a small and preterm baby had a two to three times higher risk of cardiovascular disease later in life.

Dr. Erik Ingelsson, at the Karolinska Institute in Sweden, says the increased risk appears to be lifelong.

"It seems like having a premature or small-for-gestational birth infant is a risk factor for cardiovascular disease, and thus, it is even more important to pay attention to the risk factors that you can affect, i.e., smoking cessation, eat healthy, and avoid overweight and exercise more," says Dr. Ingelsson.

A second study, this one done with data from almost 435,000 births in Denmark, came to a similar conclusion. In this study, the births occurred from 1973 to 1983, and the data came from the mothers' medical records from 1977 to 2006.

More than 27,000 of the women had at least one preterm birth, and there were nearly 41,000 cases of cardiovascular disease in the whole study population.

The researchers found that women with a history of preterm birth had 40 percent higher odds of developing cardiovascular disease than women without such histories. Women who had more than one preterm birth had a threefold increased risk of dying from cardiovascular disease.

Study lead author Dr. Janet Catov, at the University of Pittsburgh School of Medicine, says, "We don't know exactly why the risks are increased. Our hypothesis is that these women may be coming into pregnancy a little bit different. It could be that what puts them at risk for preterm birth is also related to cardiovascular disease risk later."

But, she notes, the researchers cannot know the cause for sure from this data, only that there is an association.

Dr. Catov advised women who have had preterm births to talk with their physicians about their cholesterol levels and their cardiovascular risk factors.

Study Looks at Health after Ovary Removal

The third study looked at how having the ovaries removed (oophorectomy) at the time of a hysterectomy affected a woman's health. In this study of almost 30,000 women, 44 percent had a simple hysterectomy, which left their ovaries intact, while 56 percent had their ovaries removed along with their uterus.

After 24 years of follow-up, the researchers found that women who had their ovaries removed had lower rates of breast, ovarian, and total cancers.

However, the overall risk of dying (from any cause) was increased by 12 percent in these women, and the rates of heart disease and stroke were increased by 17 and 14 percent, respectively.

The risk of lung cancer jumped 26 percent higher in women whose ovaries were removed.

In women who did not use estrogen replacement therapy, the results were even more dramatic. All-cause mortality rose by 40 percent, and the risk of heart disease and stroke was twice as high.

Always consult your physician for more information.