Kate Hudson is expecting her third baby, but first girl—and she says that is making all the difference with this pregnancy. “They say girls make you sicker and that, for me, has been the truth,” Hudson tells People. “It’s been interesting so far.”

The Fabletics mogul previously joked about just how challenging it was to deal with nausea during the first trimester or “silent months” of pregnancy. “All I wanted was a bed and a bucket and all I got was a wheel,” she says, referencing a fitness wheel she posed with for a photo shoot.

After experiencing little to no morning sickness during her pregnancies with sons Ryder, 14, and Bingham, 6, the morning sickness Hudson’s endured while expecting her baby girl has forced her to go at a different pace.

“When you become the vessel, when you have the privilege of carrying life and giving life, you have to listen, and so right now I think it is all about taking it easy,” she says, explaining she’s doing prenatal yoga for the first time. “So the things that I am doing are quite easygoing.”

Although the morning sickness is a new experience for Hudson, just how common is it among women expecting girls versus boys? A recent study sheds light on the old wives’ tale that nausea is worse during pregnancies with girls.

Some 70 to 90% of expectant mothers have some level of morning sickness, typically during the first trimester. So this alone is not a good predictor of whether they will have baby girls or boys. But, according to a study published last November before undergoing the peer review process, girl moms were more likely to remain nauseous into the second trimester. The study also linked the presence of a single protein, GDF15, in the expectant mamas’ blood to morning sickness.

Similar studies have noted an increased likelihood that a woman experiencing severe morning sickness will deliver a girl, so unlike the old wives’ tales around castor oil or hovering a wedding ring over your belly, this one actually has some scientific merit.

Still, it isn’t a sure thing—so just make sure all those girl clothes you buy online while housebound from morning sickness are refundable.

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