What's the dark line on Rihanna's pregnant belly? The linea nigra explained

During pregnancy, a woman’s body goes through many changes. But one of the more surprising and noticeable ones is a dark vertical line that appears straight down the middle of a pregnant woman’s growing abdomen. It’s called the linea nigra — which “translates to ‘black line,’” Dr. Jonathan Schaffir, an ob-gyn at The Ohio State University Wexner Medical Center, tells Yahoo Life — and it’s common during pregnancy.

In fact, Dr. Danielle Panelli, instructor of obstetrics and gynecology at Stanford Children’s Health, tells Yahoo Life: “The majority of pregnant people will usually experience some form of linea nigra development.”

The line is getting some notable attention recently thanks to Rihanna’s belly-baring maternity outfits. The star shared that she is “enjoying not having to worry about covering up my tummy” and is embracing the “incredible” changes her body is going through right now.

The dark line is also “completely normal,” Dr. Kjersti Aagaard, professor of obstetrics and gynecology at Baylor College of Medicine, tells Yahoo Life. “Nothing to worry about.”

So what exactly is the linea nigra?

“The linea nigra is a type of hyperpigmentation that commonly develops during pregnancy,” explains Panelli. “It usually looks like a line down the middle of the abdomen and can extend from your upper abdomen down to your pubic bone.”

Panelli adds: “It is actually pigmentation of a normal structure in the abdominal muscles called the linea alba.”

Hyperpigmentation, in general, is “very common in pregnancy and is related to hormone changes,” explains Panelli. She says that people generally “don’t notice it until after the first trimester,” but Schaffir says the line “typically appears in pregnancy during the second trimester.”

What causes it?

You can blame hormones for the darkening of that line. “Like other hyperpigmentation changes in pregnancy — including increased freckles, darkening of scars and darkening around the nipples and areola of the breast or the [vulvar] skin — the hyperpigmentation is thought to result from increased levels of estrogen; melanocyte-stimulating hormones, which are a group of peptide hormones produced by the skin, pituitary gland and hypothalamus and protect against UV radiation; and/or progesterone,” explains Aagaard.

Along with the areas mentioned above, hyperpigmentation during pregnancy can also occur on the face, presenting as melasma, notes Panelli.

Does the dark line ever go away?

In the majority of cases, says Panelli, “the linea nigra regresses after you give birth, but it can take a few months.”

However, Schaffir points out that “in women with a darker complexion, there may always be a faint line present — and in fact, it may have already been there before pregnancy.”

For women who are self-conscious about it, is there a safe way to cover it up?

The dark line typically fades on its own and is perfectly normal, so experts say there’s no need to conceal it. “We would generally try to reassure patients that this is a normal process in pregnancy,” says Panelli. “We would recommend you have a conversation with your doctor if you are concerned about it since there are sometimes rashes or other conditions that could affect your skin in pregnancy that may warrant a specific therapy.”

If you’re really feeling self-conscious about it, you can camouflage it with makeup. Also, avoid sun exposure, which can increase the hyperpigmentation.

Schaffir says that the linea nigra “is not dangerous and needs no treatment or cover-up, but it tends to become darker with increased sun exposure. For women who wish to minimize this and other skin darkening, it would be recommended to avoid sunlight or use plenty of sunscreen.”

Aagaard agrees, explaining that, “like other hyperpigmentation common to pregnancy, covering with a light colored shirt, sunblock or staying in the shade will limit further darkening.”

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