Morning sickness is all about the hormones. That part isn’t surprising, but what’s newsworthy is that USC researchers say they’ve discovered exactly which hormone it is — and (potentially) what can be done about it.

The hormone is called GDF15, and it’s produced by the fetus; it surges in the first trimester.

“[T]he baby growing in the womb is producing a hormone at levels the mother is not used to. The more sensitive she is to this hormone, the sicker she will become. Knowing this gives us a clue as to how we might prevent this from happening.”

Some women are especially sensitive to GDF15 and can have morning sickness that requires hospitalization. (Looking at you, Catherine, Princess of Wales.) Other woman have a genetic blood disorder that gives them chronically high levels of GDF15 so they escape morning sickness.

What can be done? One idea is to exposing moms-to-be-to-be to GDF15 before they get pregnant so their bodies have time to adjust. Another idea is to lower or block GDF15.

Messing with hormones during pregnancy is risky business, though, which is why it’s always important to talk to an expert. Who would that be? A compounding pharmacist, of course. They know hormones like the backs of their hands, and they can guide you toward making smart decisions for both you and that awesome growing bump of yours.