Most studies say that using sunscreen with oxybenzone while pregnant doesn’t seem to harm the baby’s growth, brain development, or when they hit puberty—but one study found baby boys might be a bit heavier, and another linked it to a rare bowel condition.

Studies have looked at whether a common sunscreen chemical called oxybenzone affects people’s ability to get pregnant or have healthy babies, and so far, there’s no clear link — it doesn’t seem to hurt fertility in men or women.

Using sunscreen with oxybenzone doesn't reliably mess with your thyroid hormones—some studies say it might lower them a bit, but most say it doesn't do anything noticeable, even in pregnant women.

When you put sunscreen on your skin, a chemical called oxybenzone can get into your bloodstream, and some lab and small human studies suggest it might mess with your hormones, affect baby weight depending on whether it's a boy or girl, and harm brain cells in test tubes.