Special Report: Pregnant & Over 40

had one at 40. was two days from the big 4-0 when she had hers. and were 44. was 45 and 48. was 47. is 41, and so is — the latest star to join this long and populated list of over-40 mothers. After years of rumors and public declarations of her maternal desires, the Oscar-winning beauty confirmed Tuesday that she was, in fact, expecting her first child with her 31-year-old model boyfriend , at the ripe ol’ — or is it young? — age of 41.

In the past few years, Hollywood actresses have been seemingly turning back the clock and getting pregnant closer to — and over — 40, the landmark age once deemed too old for children. So what gives? Is 40 really the new 30? Definitely, Sarah Michaud, Celebrity Baby Blog news editor, tells OK!. “I think it's part of the nationwide trend to delay marriage and, in effect, childbearing,” she says. “We're seeing many more announcements from 35 to 45-year-old celeb moms-to-be than we are from 20 to 35 year olds. Also, we're noticing many celebs are content with being married or engaged for longer periods of time before bringing children into the mix.”

And in many celeb moms’ cases, they were also content chasing their career goals, which, of course, means no diaper duty just yet. Needless to say, having kids during the prime of your career in showbiz is frowned upon. Some, such as Courteney and new mom — who turns 36 on Sept. 30 — have admitted to putting their livelihood first. “Many of these celebrities have been so focused on getting their career off the ground or keeping themselves in demand that they often place it above other wants they have, such as having children,” Sarah says. “Then they realize they don’t have much time remaining and get pregnant or begin treatments.”

Not that there’s anything wrong with career advancement. It is the 21st century after all. “Who could blame a gal for preferring to win an Academy Award over being elbow-deep in poopy Huggies?” Marcie Jones Brennan, author of Great Expectations: Baby’s First Year, tells OK!.

True, Halle can call herself the first African-American to win a Best Actress Oscar. All of the career focus and, hopefully, success pay off because “with older celebrity moms, they’re very often the main breadwinner of the relationship.” Salma’s fiancé, Yves-Saint Laurent owner and billionaire , might have something to say about that.

Natural fertility rates decline after the age of 35, Robin Elise Weiss, from About.com's Pregnancy Guide, tells OK!. “A woman who is 40 has about a five percent chance of conceiving in any given month. Even with IVF, that rate is about 10 percent because of the higher rate of abnormality in the eggs.” Unlike Marcia, some over-40 moms have not discussed whether or not they sought treatments. But regardless of medical intervention, more and more of them are getting knocked up, which may give the public false hope of conceiving later in life. “It gives people the idea that they can focus on career first, then start a family once they are established,” Sarah says. “But this glosses over the need for fertility treatments that many older mothers have.”