What’s the ideal pregnancy weight?

More women are starting their pregnancies heavier than ever before, U.S. health officials report.

In fact, in 2014, more than 50 percent of women were either overweight or obese at prepregnancy, a new report from the U.S. Centers for Disease Control and Prevention found.

“This is the first report to focus on prepregnancy body mass index (BMI) and unfortunately, it doesn’t look so great,” said lead researcher Amy Branum. She’s a statistician with the CDC’s National Center for Health Statistics.

All states, with the exception of Connecticut, New Jersey and Rhode Island, were included in the report, giving the biggest picture to date of what prepregnancy BMI looks like in the nation, she said.

Body mass index is a measure of body fat based on height and weight.

Increased prepregnancy overweight and obesity contribute to the obesity epidemic in the United States, Branum said.

“It does seem to jibe with what we see among all women in the U.S. population,” she added.

The report, released Aug. 5, found that in 2014 nearly 4 percent of women were underweight before becoming pregnant. About 46 percent of women started their pregnancies at a normal weight. But slightly more than one-quarter were overweight, and almost another quarter were obese, the report found.

Women under 20, Asian-American women, women with a college degree, women pregnant for the first time and women who paid for their own delivery were the least likely to be overweight before pregnancy, the researchers said.

Obese women were more likely to be older (over 40), black, American Indian or Alaska Native. They were also less likely to have a college degree and more likely to rely on Medicaid to pay for their delivery, Branum’s team found.

“The health implications of being overweight or obese are very real for pregnancy,” said Dr. Siobhan Dolan, a medical adviser to the March of Dimes.

Two major complications of being overweight or obese before and during pregnancy are high blood pressure and diabetes for the woman, Dolan said. These conditions can lead to problems such as early delivery and the need for a cesarean section, which can lead to complications for the mother and infant, she said.

Dolan advises all women to see a doctor before getting pregnant to help “become as healthy as you can prior to pregnancy. A lot of being healthy before pregnancy is prevention, and a healthy weight is part of prevention,” she said.

She also recommended that women with conditions such as high blood pressure and diabetes get them under control before the start of pregnancy.