You’ve been pregnant for a minute now and—finally!—your wee baby bump has begun to emerge. Exciting! A little less exciting? For many, a little something extra will piggy-back its way onto your pregnant belly: A dark line stretching from your pubic bone to your navel. This telltale sign of pregnancy is called linea nigra. Learn when this pregnancy line will appear, what causes it, when it’ll fade, and everything in between. 

What is linea nigra?

Latin for “black line,” linea nigra is a dark brown or light black vertical line that often appears on the lower abdomen during pregnancy. This pregnancy line typically runs from the pubic bone to the belly button but has been known to climb all the way to the chest. Linea nigra usually measures about a quarter- to a half-inch wide and curves slightly.

Who gets linea nigra in pregnancy?

Research shows that up to 92% of moms-to-be get pregnancy-associated linea nigra, which clearly means that most expecting parents are susceptible. That said, linea nigra is often more visible on expecting parents with darker complexions.

Fun fact: Linea nigra doesn’t just show up on parents-to-be! Experts note that it’s fairly common in newborns, too, especially little ones with more pigmented skin. In fact, a study of 1,000 Indian infants found that nearly 45% had linea nigra during their first four weeks.

What causes linea nigra?

While it may seem like your pregnancy line appeared out of nowhere, it has actually been low-key present on your abdomen at all times. Before pregnancy, the line is called linea alba and it’s nearly invisible. During pregnancy, however, a combo platter of elevated estrogen, progesterone, and melanocyte-stimulating hormones cause melanin—a natural substance that gives your skin and hair color—to rise. That uptick in melanin can result in melasma (dark spots on skin also known as the “mask of pregnancy”), darkened areolas and nipples…and linea nigra.

When does the pregnancy line typically appear?

Linea nigra usually debuts in the second trimester, around 20 weeks of pregnancy. As your pregnancy progresses, linea nigra may appear darker. (Learn more about pregnancy hyperpigmentation—and other second trimester symptoms.)

How long does linea nigra last?

Linea nigra doesn’t magically disappear once a baby arrives. Instead, the line will gradually fade as hormone levels return to their pre-pregnancy state—a process that can take several weeks to months. And that’s a good thing! Some experts speculate that the dark line may help newborns find their way up to the breasts to nurse.

That said, for some, linea nigra lightens but never fully fades, instead leaving a faint but permanent reminder of pregnancy on your abdomen. Another weird souvenir of pregnancy: Linea nigra is often accompanied by the “displacement of the umbilicus to the right.” What that means is, your belly button may shift ever so slightly to the right side!

Can you prevent or reduce linea nigra?

While there are no iron-clad strategies to prevent linea nigra, it is possible that consuming ample folic acid and folate may reduce the chance of developing the pregnancy line. (But even if you aren’t put off by a belly line, folate-rich foods—like leafy green, lentils, and oranges—and a folic acid supplement help prevent neural tube defects.)

Living that sun’s-out-bump’s-out life? Make sure you thoroughly slather your belly in sunscreen that’s free of the ingredient oxybenzone. And don’t use any medications or bleaching agents to try and fade your pregnancy line. Many over the counter and prescription skincare products are unsafe for pregnancy. (Learn which skincare products are safe in pregnancy.)

Will I get the pregnancy line with each baby?

Probably. Experts note that once you get linea nigra in pregnancy, you are more likely to get it with each additional pregnancy. Nevertheless, your pregnancy line may look darker or lighter—or appear earlier or later—than prior pregnancies.

Does linea nigra predict Baby’s gender?

It’s thought that if your pregnancy line runs from your belly button downward, you’re having a girl…but if it stretches from your pelvis up to your ribcage, it’s a boy. While it can be fun to try and predict if you’re having a boy or a girl by how you’re carrying your baby, your cravings, how a pendulum swings over your bump…or where your pregnancy line stops and starts, these are all simply fun old wives’ tales.

Linea Nigra: When to Consult Your Healthcare Provider

Good news! Linea nigra during pregnancy is perfectly normal and not associated with any medical conditions. However, if you notice any other dark areas of skin on your abdomen, flag them on your next prenatal visit. There are some health conditions that can show up as a dark patch of skin.

 

More on Pregnancy Symptoms:

• Pregnancy and Shortness of Breath: When to Worry
• All About Swollen Feet and Ankles in Pregnancy
• First Trimester Symptoms and Solutions
• Third Trimester Symptoms and Solutions

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REFERENCES

• Cleveland Clinic: Linea Nigra
• Morphological changes of the fetal umbilical cord at term pregnancy, Journal of Morphological Sciences, January 2015
• The mystery of the linea nigra: a literature review and prospective study of its presence and associated conditions, Clinical and Experimental Obstetrics & Gynecology, December 2023
• Stanford Medicine: Newborn Nursery at Lucile Packard Children's Hospital: Linea Nigra
• Pregnancy Birth and Baby: Skin changes during pregnancy - linea nigra
• Pigmentary changes of pregnancy, Clinics in Dermatology, May-June 2019
• Eastern Idaho Regional Medical Center: Boy or Girl? Wacky Pregnancy Myths About Gender

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Disclaimer: The information on our site is NOT medical advice for any specific person or condition. It is only meant as general information. If you have any medical questions and concerns about your child or yourself, please contact your health provider.