Stilettos and pregnancy is never a good thing. Who is Alicia Keys’ obstetrician? Had it been me, she would have received the infamous lecture I’ve been giving my patients for years: the curvature of a pregnant woman’s spine is exaggerated and there is an increased risk of falling – especially in a pair of high-heels.

Alicia was in New Orleans, performing at the Essence Music Festival. In the midst of her performance, she leaned backwards with the mike held high, stepped back in what appeared to be 5-inch stiletto heels, and tumbled to the floor. Gratefully, she landed on her buttocks. She quickly got up, then sat down at the piano and continued to sing without missing a beat. Why did Alicia fall?

The pregnant body undergoes significant hormonal and mechanical changes to the pelvic bones. The curvature of the lower back is exaggerated and called lordosis. This is what helps a pregnant woman lean back and avoid tipping over like a bowl as her uterus enlarges. A recent anthropology study by Katherine Whitcome at Harvard University discovered the curve of a woman’s back extends across three vertebrae as opposed to just two in men, giving it more stability. However, when a pregnant woman puts on a pair of 5-inch heels, she’s really pushing the envelope.

Pregnant moms should be aware that the joints of the pelvic bones will become soft and slightly separate as a result of a hormone called relaxin. This is what causes pregnant women to “waddle” like ducks. Pregnancy also causes the center of gravity (or the greatest concentration of weight) to change as the uterus enlarges.

Is a pregnant woman banned from wearing heels altogether? Of course not. The American College of Obstetrician-Gynecologists recommends that pregnant moms wear 1 to 2-inch shoes. Contrary to popular belief, flat shoes are NOT recommended because they do not offer good arch support.

So pregnant moms, feel free to look pretty, but please stay away from those 5-inch heels.