A nationwide crackdown on drunken driving that starts tomorrow will feature sobriety checkpoints, saturation patrols and a multimillion-dollar advertising campaign.

It also will focus on women, who represent a growing percentage of drunken drivers, U.S. Transportation Secretary Ray LaHood said yesterday.

"Impaired driving is an issue that cuts across all segments of society and, sadly, the number of arrests of women driving under the influence is on the rise. This is clearly a very disturbing trend," Mr. LaHood said at a news conference in Washington, D.C.

He cited FBI statistics showing that arrests of women driving under the influence increased by nearly 30 percent from 1998 to 2007. Over the same period, DUI arrests of men decreased by 7.5 percent, although men still were arrested four times as often as women.

An analysis by the National Highway Traffic Safety Administration showed that the number of impaired women drivers involved in fatal crashes increased in 10 states last year, including Ohio and West Virginia, despite an overall decline of 9 percent in drunken driver crashes. In Pennsylvania, the number of female drunken drivers in fatal crashes declined from 67 in 2007 to 54 last year.

"Women are driving more like men and, unfortunately, have picked up some of their dangerous habits," said Barbara Harsha, executive director of the Governors Highway Safety Association, which is participating in the enforcement blitz.

Laura Dean-Mooney, president of Mothers Against Drunk Driving, said it was unclear why there has been an increase in the number of women arrested for impaired driving.

"What you're hearing more is that women are under more pressure, they're now perhaps the breadwinner because of the unemployment rate," she said.

"We need to make sure women understand that if you're a drinking driver, you're just as likely as a male to hit or kill or injure someone or perhaps even kill yourself."

The crackdown, which runs through Labor Day, is called "Drunk Driving. Over the Limit. Under Arrest."

Some 11,000 law enforcement agencies will take part. The effort features a $13 million national advertising campaign that began yesterday, augmented by state-funded ads, Ms. Harsha said.

"It involves every single state."

Last year, 11,773 people died nationally in crashes involving a driver whose blood alcohol level was 0.08 or higher. That represented a 9.7 percent decrease compared with 2007.

DUI deaths also declined in Pennsylvania, from 504 in 2007 to 496 last year. Those deaths made up 34 percent of crash fatalities in the state.

Still, the safety association said, the number of fatalities was "completely preventable."

August and September are among the worst times for drunken driving casualties, Ms. Harsha said.

In Pennsylvania, more than 600 municipal police departments, all state police troops and several university police forces are expected to take part in the crackdown, the safety association said. Pennsylvania Department of Transportation safety press officers are organizing events at colleges and high schools to publicize it.

PennDOT District 11, covering Allegheny, Beaver and Lawrence counties, will hold an event at Northgate High School tomorrow to announce the crackdown, which will feature "a lot of DUI enforcement" including roving patrols and checkpoints, said David Pritt, safety press officer.

The Governors Highway Safety Association yesterday also cited progress in the legislative war on drunken driving, saying three more states have enacted laws requiring first-time convicted DUI offenders to have alcohol ignition interlocks installed on their vehicles.

The devices measure blood alcohol content through a breath test before the car is allowed to start. Ten states now require them for all DUI offenders: Alaska, Arizona, Arkansas, Hawaii, Illinois, Louisiana, Nebraska, New Mexico, Utah and Washington.

Pennsylvania requires the devices for those convicted of a second or subsequent DUI.