LOS ANGELES — First came love. Then came marriage.
And the baby carriage? Meh.
"Just the two of us is awesome," said Sara Tenenbein, a 30-year-old blogger and consultant living with her husband in Los Angeles. "Maybe we don't need to add more humans to the equation."
Not having children is still rare among married women like Tenenbein, but less so than it used to be, according to an analysis by the National Center for Family & Marriage Research at Bowling Green State University, which examined figures from the National Survey of Family Growth.
The percentage of married women ages 40 to 44 who had no biological children and no other kids in the household, such as adopted children or stepkids, reached 6 percent in the period between 2006 and 2010. That's a small but statistically significant jump since 1988, when only 4.5 percent of married women had no kids.
The increased numbers echo a wider trend over recent decades, as more American women have reached their 40s without bearing children. Federal statistics on older women suggest some found themselves unable to have children, while others chose not to have them. Some may still be planning to raise children later in life.
Most women who don't have children are not married _ and the vast majority of married women ultimately have kids, federal statistics show. In fact, the dropping marriage rate is one of the biggest forces behind increased childlessness, Arizona State University associate professor Sarah Hayford found.
But the uptick in childlessness among married women, albeit slight, is another sign of the evolving meaning of marriage, said Susan L. Brown, co-director of the National Center for Family & Marriage Research.
Marriage is slowly becoming less firmly hitched to child rearing, as ideas about why to wed have shifted, and rearing kids out of wedlock becomes more common. Putting off parenthood also has given married couples more time to weigh whether they want children at all.
"There's a resistance to parenthood being the default after marriage," Childless by Choice Project director Laura S. Scott said. "People are questioning it in ways that they didn't perhaps 30 or 40 or 50 years ago."
Growing up in Indiana, Kate Sherrill had assumed she would marry and have children. It was just what people did, she said. But when Sherrill had trouble meeting someone she connected with, she began rethinking what her life might look like. Did she want children? Was marriage important to her?
The Indiana librarian ultimately found love at a showing of "The Rocky Horror Picture Show." She and her husband, John House, didn't rule out having children when they married. But neither of them felt the pull of parenthood. Nine years later, that hasn't changed.
Sometimes they run into people who "can't seem to wrap their mind around it," said Sherrill, now 40. "They say, 'Oh, you couldn't have kids?' And we say, 'Uh, we don't know. We didn't try.'"
A Pew Research Center survey three years ago found that Americans rated love, lifelong commitment and companionship as more important reasons to wed than having children. Earlier Pew surveys found a shrinking percentage of adults who said children were very important to a successful marriage.
"We've moved away from the idea that the sole or even the primary purpose of marriage is to produce offspring," said Debra Mollen, associate professor of psychology at Texas Woman's University. Instead, "we want someone to share our lives with."
For stand-up comedian and writer Steve Hofstetter, growing up Jewish came with pressure to marry someone Jewish and have kids "to repopulate the Earth with Jews."
"From the time I was 13 years old I felt like I was John Connor trying to save civilization," Hofstetter joked, referring to a character in the "Terminator" movies. The 34-year-old met his wife _ Tenenbein _ through the Jewish dating web site JDate, but the two aren't planning to have children.
"We wouldn't have the life we wanted," Hofstetter said, "and we'd resent them."
Couples might also shy away from becoming parents because it has become a more intense job: Parents now spend more time and money on their children than they did decades ago, studies from the Pew Research Center and the journal Demography show.
Last year, more Americans agreed that "having children interferes too much with the freedom of parents" than in 1994 or 1988, according to the General Social Survey, a project of NORC at the University of Chicago.
Such worries loom especially large for the ambitious: In 1992, more than three-quarters of students graduating from the Wharton School of the University of Pennsylvania said they planned to have or adopt kids; less than half said the same in 2012, research published in the new book "Baby Bust" found.
Yet choosing not to have children is still the exception, not the rule.
Couples in groups for the proudly child-free still complain about stigma. Despite the demands of parenthood, the vast majority of Americans _ 90 percent _ either have children or want to have them, a recent Gallup poll showed.