Noticed a dark vertical line between your belly button and pubic area during pregnancy? That's your linea nigra, and it was actually always there — it just gets a bit darker when you're expecting.

When Does the Linea Nigra Show Up?

The zipper down the middle line of your swelling belly tends to get a little darker by the second trimester (sometimes around week 23 of pregnancy).

What Causes Linea Nigra During Pregnancy?

Pregnancy hormones are behind the appearance of the linea nigra (Latin for “black line”). The condition is the darkening of your linea alba, the “white line” of skin you'd probably never noticed that runs between your belly button and your pelvis. In fact, the skin all over your body becomes hyperpigmented, or darkened, during pregnancy (you might also notice the skin on your face darkening too, known as melasma, or the “mask of pregnancy,” as well as newly darkened areolas). The linea nigra is likely to be more pronounced if you have darker skin.

A fun old wives' tail (which is not, of course, backed by science): If the linea nigra runs only up to your navel, you're having a girl, but if it runs past your belly button to up near your ribs, it's a boy.

What You Can Do About the Linea Nigra During Pregnancy

A couple of quick tips can help make the linea nigra less pronounced:

  • Cover up. Spending too much time working on your tan can intensify skin discoloration during pregnancy – so use sunscreen (at least SPF 30) and try to keep your tummy covered up as much as possible.
  • Eat well. Folic acid deficiency can be related to hyperpigmentation, so make sure you're eating a healthy pregnancy diet with plenty of folate from green leafy vegetables, fruits and whole grains, and be sure to take your prenatal vitamin.

Can I Prevent Linea Nigra During Pregnancy?

The best way to prevent or minimize the appearance of the linea nigra is to avoid exposing your skin to the sun. So wear clothing over as much of your body as possible, and slather any skin that is exposed in sunscreen.

When Does the Linea Nigra Go Away?

The linea nigra should gradually fade all on its own a few months after your baby is born.

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