Last month, Janet Jackson welcomed her first child at the age of 50.  This month, at ages 35 and 39 respectively, Beyonce and Amal Clooney announced they were both expecting twins. By medical standards, all three women are considered to be at advanced maternal age.

"After age 35, you are considered advanced maternal age," said Dr. Constantine Economus.

More and more women are putting their careers first and planning their families second.  However, experts says that doesn't mean women can't or shouldn't consider trying to have families once they reach their 30s.

"After age 35, we tell women to try for six months or so and then we can start talking.  At 40, we get involved immediately," said Dr. Economus.

Dr. Constantine Economus says conceiving at advanced maternal age may require a little more effort.  The older women get the more likely they're going to need medical interventions such as an egg donation or IVF.

"We do know that your fertility decreases with age and it begins at age 32 and it accelerates at age 37,"  

There are also risks to babies of women who conceive at advanced maternal age.  The biggest is genetic risks, such as down syndrome.  After the age of 35, the risk of having a baby with down syndrome is 1 in 270.