Can you guess the "ideal age" to get pregnant, according to a fertility doctor?

For women who want to have children, planning the right time is a difficult decision. In recent years, many women have opted to put off having kids until their late 20s and well into their 30s—focusing on finishing school, building their careers, traveling, and maybe even paying down their student loans before taking the leap into parenthood. Statistics show that women are waiting longer and longer to have kids—the current average age of first-time moms is up to 26.3, up from 24.9 just 15 years ago.

The choice to have children is extremely personal and of course there’s no wrong answer when it comes to being ready to be a mom. But according to Dr. Gillian Lockwood, medical director at the Midland Fertility Clinic in the U.K., there is an ideal age when our bodies are best suited to pregnancy. Can you guess what it is?

I’ll give you a hint: it’s when many of us have a quarter-life crisis. Also: when it finally becomes affordable to rent a car. Yep. According to Lockwood, the ideal age to get pregnant is 25.

Unfortunately, says Dr. Lockwood, it’s also the age when motherhood is low on many women’s list of priorities. She explained in the Evening Standard:

Age 25 is exactly the time when today’s young women have left university, are trying to get off on a good career, trying to pay back their student loans, trying to find someone who wants to have babies with them and trying to get on the housing ladder.”

Dr. Lockwood also had some harsh words about fertility treatments being marketed as a viable option to women over 40. “The bleak reality is that the chance of IVF working with your own eggs once you are 40 is absolutely abysmal,” she said. “In what other branch of medicine would we let, yet alone encourage, patients to pay for an elective operation with a less than five percent chance of working?” While that may be Dr. Lockwood’s opinion, plenty of wannabe parents may be happy to take those chances.

It’s worth reiterating that there are so many factors that inform the choice to have kids and only you can decide when—and IF—you want to become a mother.

Whether you choose to have kids at 20, 30, 40, or beyond; biologically, through a surrogate, or via adoption, always listen to your own body and make the decision that makes sense for your own life. You know what’s right for you.