When Does The Linea Nigra Appear?

By Dr. Kenosha Gleaton, OBGYN

With pregnancy comes a lot of change, both mentally and physically. One physical change that many people will notice during pregnancy is the appearance of stretch marks. It’s very common for stretch marks to appear on the belly, butt, thighs, and elsewhere. It’s also common for a darker line to appear that stretches from the pelvic region to the belly button. Let’s chat a bit more about this line, and when you can expect it to appear. 

What Is The Linea Nigra?

The linea nigra, Latin for “black line”, is the dark vertical line that sometimes appears on the skin of the stomach during pregnancy. This line runs from the belly button to the pubic area and can sometimes extend towards the abdomen and breasts. [1] The linea nigra is sometimes called the “pregnancy line” and may get darker as pregnancy progresses. Typically this line will be a brown or light black color and ranges from about 1⁄4 to ½ inch wide. [2] 

What many people don’t realize is that the linea nigra is always present, but is actually known as the linea alba (white line) when it isn’t visible and darkened. [2-3] This line is actually a band of fibrous tissue that is a meeting point for various abdominal muscles. If you picture defined abs, the linea alba is actually the tissue that runs right down the middle. 

What Causes the Linea Nigra?

There isn’t a confirmed cause of the linea nigra, however most researchers theorize that hormone levels play an important role. One theory is that the linea nigra forms as a result of the melanocyte-stimulating hormone created during pregnancy which causes melanin to rise, darkening the skin. [1-2] This hormone is also behind the darkening of areolas during pregnancy and melasma, a skin condition sometimes experienced during pregnancy. We do know that linea nigra is a pigmentary change, meaning that only skin pigment is changing and there is no reason to be concerned about the health of the pregnancy or skin. [2] 

Is It Common to Get a Linea Nigra?

Yes, it’s considered a very common and normal occurrence for pregnant people to develop a linea nigra. In fact, the linea nigra is thought to appear in up to 80% of pregnant people. [1-2] Those with darker skin colors do tend to have a more pronounced linea nigra compared to those with lighter skin colors, but the linea nigra can appear in anybody.  It’s not unheard of for a linea nigra to appear in nonpregnant people as well. This isn’t as likely to occur, but is also thought to be connected to hormone levels and isn’t considered to be a troubling symptom, though you should speak to a healthcare provider if you notice a linea nigra and you aren’t pregnant. [2] 

When Does the Linea Nigra Appear?

So when can you expect the linea nigra to appear? Technically the linea nigra is always present but is usually invisible until there is a rise in hormones. [2] Many people will start to notice the linea nigra appear in their second trimester at about 20 weeks gestation. [1-2] 

When Will the Linea Nigra Disappear?

There’s no telling if or when the linea nigra will disappear completely, but many people will notice that the line fades a few weeks to a few months after giving birth. It’s also normal for a few years to pass before there is noticeable fading.  [2] Read up on whether or not stretch marks go away after pregnancy → 

Treating and Preventing the Linea Nigra

There isn’t a confirmed method for preventing the linea nigra from forming or for making it go away. As mentioned already, the linea nigra is always present but may not always be visible. Pregnancy hormones are what cause the line to become more pigmented. There are some topical ointments, creams, and medications that can be used to reduce pigmentation, but most of these products are strongly discouraged during pregnancy. [1-2] If you are interested in these options after giving birth, speak to your healthcare provider about any safe or recommended options you can use.

Some data suggest that folic acid may be useful for reducing the intensity of the linea nigra. You can find folic acid in foods such as beans, oranges, leafy green vegetables, and whole wheat bread, or opt for a supplement such as Natalist Folate. [1] Using sunscreen may also prevent the linea nigra from getting much darker and can protect your skin from harmful ultraviolet rays. [2] 

Caring for Stretch Marks 

Speaking of treating and preventing the linea nigra, many people wonder what they can do to reduce the appearance of stretch marks. Stretch marks are a very common occurrence, appearing in up to 90% of pregnant people, and are nothing to be ashamed of. [4] It’s natural for the body to change after completing such an impressive feat! 

All of that being said, there is little evidence that any remedies can actually prevent or remove the appearance of stretch marks. Some data does suggest that hydrating the skin regularly may help improve skin elasticity and reduce dry or itchy skin [5] (Learn more about treating itchy stretch marks). Some studies also show that collagen peptides support skin elasticity and help with the regeneration of skin, which may be helpful for treating stretch marks in some people. [6-7] If you are looking for pregnancy-safe products that can keep your skin moisturized and glowing, you may want to consider the Pregnancy Self-Care Bundle which includes belly oil, cooling cream, and more. 

Key Takeaways

• The linea nigra is a dark vertical line that appears in about 80% of pregnant people.
• The linea nigra stretches from the pubic area to the belly button and can sometimes continue up towards the sternum.
• The linea nigra is technically always present but is known as the linea alba when it’s not dark and visible. 
• It’s thought that hormones are what cause the linea nigra to appear.
• Many people will start to notice the linea nigra appear in their second trimester at about 20 weeks gestation.
• There’s no telling if or when the linea nigra will disappear completely, but many people will notice that the line fades a few weeks to a few months after giving birth. 
• There are no proven ways to prevent or get rid of stretch marks or the linea nigra, but keeping the skin moisturized, protecting it from the sun, and supplementing with folic acid may all be helpful for reducing the appearance. 
• Natalist Belly Oil is made with pregnancy-safe ingredients that keep the skin moisturized and dewy. 

References:

1. Vora RV, Gupta R, Mehta MJ, Chaudhari AH, Pilani AP, Patel N. Pregnancy and skin. J Family Med Prim Care. 2014;3(4):318-324. doi:10.4103/2249-4863.148099
2. Linea Nigra. Cleveland Clinic. July 18 2022. https://my.clevelandclinic.org/health/body/23488-linea-nigra 
3. Linea Alba. Cleveland Clinic. July 2022. https://my.clevelandclinic.org/health/body/23483-linea-alba
4. Wollina U, Goldman A. Management of stretch marks (with a focus on striae rubrae). J Cutan Aesthet Surg. 2017;10(3):124-129. doi:10.4103/JCAS.JCAS_118_17
5. What causes stretch marks during pregnancy? American College of Obstetricians and Gynecologists. October 2020. https://www.acog.org/womens-health/experts-and-stories/ask-acog/what-causes-stretch-marks-during-pregnancy
6. Bogdan C, Moldovan ML, Man IM, Crișan M. Preliminary study on the development of an antistretch marks water-in-oil cream: ultrasound assessment, texture analysis, and sensory analysis. Clin Cosmet Investig Dermatol. 2016;9:249-255. Published 2016 Sep 6. doi:10.2147/CCID.S107298
7. Al-Atif H. Collagen Supplements for Aging and Wrinkles: A Paradigm Shift in the Fields of Dermatology and Cosmetics. Dermatol Pract Concept. 2022;12(1):e2022018. Published 2022 Jan 1. doi:10.5826/dpc.1201a18