Allyson Y. Schwartz remembers her early days in the Pennsylvania Senate during the 1990s, when her sons were in middle and high school. "It was a lot of evenings and weekends," said Schwartz, now U.S. representative from the 13th District, "and I would run home, eat dinner with them, and then run back out again."

At the time, Schwartz was only the third woman to serve in the state Senate. But these days, Schwartz's story is being played out by a record number of Capitol Hill congresswomen.

Three women gave birth during the 110th Congress, and as the 111th Congress takes its seats this month, another new baby is on the way - which brings the total number of moms raising young children and babies to 10, a group that includes single moms as well as the first unwed mother ever in Congress.

It's a paradigm shift from 1958, when Rep. Coya Knutson lost her bid for a third term largely due to a letter her husband released to the press, exhorting her to "go home and make a home for your husband and son. . . . "

Or, when Pat Schroeder of Colorado arrived in Washington in 1973 with a 2-year-old and a 6-year-old in tow - such an unusual scenario that Schroeder was asked how she intended to work in Congress and raise small children at the same time. She famously replied, "I have a brain and a uterus, and I use both."

Schroeder remained on Capitol Hill for 24 years, one of a small number of women - and a smaller number of mothers - who were in Congress during the heyday of the women's movement. But it wasn't until 1995 that Rep. Enid Greene of Utah gave birth in office (22 years after Yvonne Brathwaite Burke was the first to do so).

The pace has suddenly quickened: One congresswoman gave birth in 2007, two in 2008, and another is due this spring. Like Schroeder, all seem positioned for the long haul, as one is the vice chair of the House Republican Conference and three are members of House Speaker Nancy Pelosi's 30-Somethings, a coterie of 11 men and women members in their 30s and early 40s.

These women, making up a record-breaking 17 percent of the 111th Congress, are markedly different from their 20th-century predecessors, who were traditionally older than their male counterparts and less likely to have children under 18 living at home, according to Debbie Walsh, director of the Center for American Women and Politics at Rutgers University.

Many of the early congresswomen won their seats via the "Widow's Mandate" - appointment of a wife to fill her deceased husband's seat. In fact, Pennsylvania has sent three women to Congress by that route (and only seven women total to the Hill, to date, contributing to the state's poor ranking, 44th out of 50 states, for number of women in office).

That pattern began to shift in the 1970s when, for the first time, 48 percent of the women in Congress were elected on the basis of their own experience and the average age of congressional women dropped below 50.

According to Matt Wasniewski, historian and deputy chief of the Congressional Office of History and Preservation, every congressional election since 1992 has seen the arrival of, on average, 10 additional women on the Hill.

Those demographics have helped institute a number of mother-friendly changes on the Hill, including a nursing room and a day-care center - significant for an institution that didn't offer female senators a bathroom near the Senate floor until the 1990s. Says Schwartz, "Congress has not easily accommodated to change."

While no one is keeping statistics on the number of mothers in Congress, they seem to be constituting a mini-trend of their own. "It's a fascinating moment," said Walsh. "For men, the photo of the wife and the kids and the golden retriever is priceless. It shows they have a stake in the community. For women, they bring their kids on the campaign trail and the first question is, who's gonna take care of the kids if you're elected?"

That question was frequently raised to Alaska Gov. Sarah Palin when she was running for vice president on the Republican ticket. Sally Quinn, writing in the Washington Post, said, "When the phone rings at 3 in the morning and one of her children is really sick, what choice will she make?"

But female politicians say critics ignore how similar they are to other working mothers. "Like any working parent, I find it can be a challenge to balance family life with my work responsibilities," says Sen. Blanche Lambert Lincoln of Arkansas, who went on the campaign trail when her twin sons were 1.

Politics, after all, happens 24/7, says Schwartz, but it also can offer more adaptability for parents.

"My job does offer me a lot of flexibility that a lot of parents don't have," says Rep. Cathy McMorris Rodgers, who gave birth to son Cole in 2007. "I don't have to punch the clock, so I can carve out time to help meet Cole's needs."

Carving out time has, ironically, become more difficult with a female House speaker. Under Republican (and male) control, the House was in session Tuesday through Thursday, so most representatives left their families at home - then they'd return for a four-day weekend. But Pelosi has put the House on a Monday-through-Friday schedule, increasing the challenges for congressional parents who don't want to be away from their small children five of every seven days.

McMorris Rodgers and others are responding by settling in D.C. "We chose to buy the house [in Washington] so I could be close to the Capitol and still be with my family," the congresswoman says.

Moving families to Washington has long been a practice of the Senate, but it's unusual for House members, who must run for reelection every two years.

"Politics has a basic bias against families because of the two-year election cycle," says former Rep. Deborah Pryce of Ohio, first elected to Congress in 1993 when her daughter Caroline was 2. After Caroline died in 1999 of cancer and Pryce and her husband subsequently divorced, she adopted Mia in 2002, the same year she was elected chair of the House Republican Conference. "I promised myself I wouldn't raise her in D.C.," Pryce said. So Mia stayed behind in Ohio and Pryce commuted every week. Eventually, as Mia got older, "she needed me at home," so Pryce opted not to run for reelection in 2008.

Women still make up a minority of politicians on Capitol Hill, but consider the attitude shift since a male colleague said this to Rep. Millicent Fenwick during a debate about equal rights legislation: "I just don't like this amendment. I've always thought of women as kissable, cuddly and smelling good."

To which the redoubtable Fenwick replied, "That's the way I feel about men, too. I only hope for your sake that you haven't been disappointed as often as I have."