Linea nigra refers to the dark vertical line that usually appears on the abdomen during pregnancy. Although it is associated with pregnancy, some women may experience linea nigra without pregnancy (1). Environmental factors and certain hormonal changes may usually be responsible for linea nigra in non-pregnant women. The linea nigra usually goes across the abdomen, passing through the belly button towards the lower abdomen (2). The common cause of it during pregnancy is the melanocyte-stimulating hormone, causing linear melanin deposit. Read this post to know the various causes of linea nigra with and without pregnancy.

How Does A Linea Nigra Look Like?

The clinical features of linea nigra are (2) (3):

Typically it measures around a centimeter in width and is a vertical line from your belly button to your pubic bone. Width of the linea nigra may increase during pregnancy. Can also extend up to the upper abdomen. Prominence may vary depending on your skin tone. Dark color of the line can vary from brown to grayish-black. Linea nigra is different from melasma (mask of pregnancy), a skin condition with dark patches on the face. The origin of melasma is also due to hormonal variations, and patches may stay for long or disappear after pregnancy.

Can You Have Linea Nigra Without Pregnancy?

The linea nigra can appear in a non-pregnant woman due to hyperpigmentation. According to the Journal Of The National Medical Association, linea nigra may be found in 75% of women during pregnancy (5). It also reports that 8% of non-pregnant women may have the dark line. The study also finds the involvement of certain co-factors to manifest the dark line. The appearance of linea nigra is most often an aesthetic issue, and its appearance does not raise any concern. The dark line can appear in male and female populations at any age (5). If the dark line is bothering you, consult your physician to understand any clinical relevance. Your doctor may suggest some laboratory tests to understand any underlying health issues. Dr. Kimberly Langdon, a US-based obstetrician/gynecologist, says, “Hormonal imbalances, such as polycystic ovarian syndrome (PCOS), cushing’s disease, and addison’s disease, can cause hyperpigmentation. These pathologies increase melanocyte-stimulating hormone (MSH), which causes excessive melanin formation and is the same hormone that causes the pregnancy line to form. As a result, even if you are not pregnant, you can develop linea nigra.” Some causes of linea nigra in non-pregnant women are (3) (4) (6) (7):

Age: Hormonal changes during puberty and menopause may contribute to skin darkening and linea nigra. Hormones, such as estrogen, accelerate melanin production. Sun exposure: Prolonged sun exposure without protection from sunscreen or clothing might cause hyperpigmentation.

Hormonal birth control: Birth control pills containing estrogen can trigger melanin pigmentation and cause linea nigra.

Pseudocyesis: False pregnancy (pseudocyesis) can also cause linea nigra. Addison’s disease: Abnormality in the adrenal gland can trigger an increase in the melanin levels in the body. This may also cause a linea nigra and darkening of the skin in the belly region. Polycystic ovary syndrome (PCOS): PCOS is a hormonal disorder accompanied by enlarged ovaries. It is associated with elevated androgen levels (male hormone), which causes skin darkening.

When Does Linea Nigra Appear During Pregnancy?

The dark line appears in response to the hormonal changes during pregnancy. Following are the clinical features of linea nigra (3):

The line usually appears in the second trimester; however, it can appear anytime during the pregnancy. The line may naturally fade into a lighter shade after childbirth and become indistinguishable at times. In some cases, the line may stay for longer. The line can reappear in subsequent pregnancies.

How To Get Rid Of Linea Nigra Naturally?

Some natural remedies may help improve the skin darkening (3) (8) (9):

Cocoa butter is widely used for aesthetic purposes. It moisturizes the skin and keeps it tender. It also helps reduce stretch marks and linea nigra.

Coconut oil helps moisturize the skin and ease the linea nigra and stretch marks on the body. Vitamin-E oil can be applied to darkened skin or stretch marks. Regular application can help improve skin conditions. Lemon juice has skin healing properties and may help lighten the dark line on your belly.

The deficiency of some nutrients such as folic acid might be causing skin darkening. Improving lifestyle and nutritious diet may help gain healthier skin. Food such as green vegetables and cereals are a good source of folic acid. Nutgrass (Cyperus rotundus) extracts help improve linea nigra.

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