Pregnancy pounds can boost cancer risk More than 38-pound gain can put breasts in danger

SAN FRANCISCO--In a new twist on the dangers of extra weight, astudy found that women who gain too much during pregnancy face anincreased risk of breast cancer later in life.

Doctors have long known that obesity increases a woman's chance ofbreast cancer. Staying slim is one of the few things a woman can dothat clearly lowers her risk.

But the latest study suggests that piling on the pounds duringpregnancy may be especially hazardous.

The study, presented Tuesday, found that women who put on morethan 38 pounds during pregnancy had a 40 percent increased risk ofdeveloping breast cancer after menopause. The risk before menopausewas no higher than usual.

Fat cells produce estrogen, and many believe the extra hormone iswhat puts overweight women at higher risk of breast cancer. Dr. LeenaHilakivi-Clarke, who directed the study, said that getting a burst ofestrogen during pregnancy may be especially bad.

"During times when the breast is rapidly developing, estrogenmight be particularly harmful. Pregnancy is one such period," shesaid.

Hilakivi-Clarke, a researcher at Georgetown University, presentedthe findings at a meeting in San Francisco of the AmericanAssociation for Cancer Research.

But Dr. Eugenia Calle, director of analytic epidemiology at theAmerican Cancer Society, questioned whether weight gain duringpregnancy is any worse than weight gain in general.

Many women fail to take off all the extra pounds after they givebirth. Calle said women who put on an extra 30 to 50 pounds duringadulthood face about double the usual risk of breast cancer afterthey reach menopause. "The message to women is to maintain theiryoung adult weight through life," she said.

Hilakivi-Clark said her team has not yet examined whether womenwho gain extra weight during pregnancy and then take it all off havean increased risk of later breast cancer.

Her study was based on a followup of 4,020 postmenopausal women inFinland, 185 of whom developed breast cancer at an average age of 58.The researchers checked medical records to see how much the womengained during pregnancy.

Guidelines from the Institute of Medicine say how much women needto put on depends on their body mass index, a widely used measure offatness.

A woman who is underweight should gain 28 to 40 pounds. One who isnormal weight should gain 25 to 35 pounds. Someone who is overweightshould add 15 to 25 pounds. And obese women should put on no morethan 15 pounds. AP