Women who suffer physical or verbal abuse during pregnancy may be at risk of complications ranging from low birth weight to newborn death, a new study shows.

Moreover, researchers found, the women at greatest risk of complications may be least likely to report the abuse.

In a study of more than 16,000 women who gave birth at one Texas hospital, 5 percent said they had been verbally abused by a partner or family member during their pregnancy, while about 1 percent reported physical abuse, the investigators found.

Women who said they’d been verbally abused - defined as being “screamed or cursed at,” threatened with harm or insulted - were more likely to have a low-birthweight baby than women who reported no abuse. And among those who said they’d been physically abused, there was a heightened risk that the baby would die around the time of birth, according to findings published in the journal Obstetrics & Gynecology.

But it was the small number of women who refused to be interviewed for the study who had the highest rates of several complications - including premature delivery, low birthweight and the need for newborn intensive care. They were also the least likely to get prenatal care.

“We can only speculate that women who declined to be interviewed were abused and fearful of retaliation,” said the study’s lead author, Dr. Nicole P. Yost of the University of Texas Southwestern Medical Center in Dallas.

If that’s the case, she and her colleagues conclude in their report, “women who remain silent when questioned about the subject may, in fact, be speaking the loudest.”

Exactly what to do about the problem is unclear, Yost told Reuters Health, but doctors should “let women know we’re there for them.”

The American College of Obstetricians and Gynecologists recommends that obstetricians routinely screen pregnant women for domestic abuse, Yost pointed out. But at least one survey has found that many doctors don’t ask those questions, though they are more likely to when they suspect abuse.

The women in the current study all gave birth at Parkland Memorial Hospital, which specializes in serving low-income, uninsured patients, between 2000 and 2002. Each was asked whether she had suffered any verbal or physical abuse from a partner or family member during her pregnancy, and those who had were referred to a violence intervention center.

Among women who reported verbal abuse, 8 percent had a low-birthweight baby, compared with 5 percent of women who reported no abuse. And while there were few newborn deaths in the study, women who’d been physically abused did have a higher rate - 1.5 percent, versus 0.2 percent among non-abused women.

But it turned out that women who refused to be interviewed about domestic abuse - less than 1 percent of all those the researchers approached - had the poorest pregnancy outcomes.

Thirteen percent of these mothers had a low-birthweight infant, nearly three times the rate of women who reported no domestic violence. They also had the highest rates of preterm delivery and newborn intensive care in the study.

It’s unclear whether verbal and physical abuse directly cause poor pregnancy outcomes, or somehow indirectly lead to complications, according to Yost. More research, she said, is needed to answer those questions.

SOURCE: Obstetrics & Gynecology, July 2005.