1 pregnancy-related skin change that can look like skin cancer — and how to tell the difference

• It's natural for skin to change throughout pregnancy, from dark patches to redness.
• Moles can also get darker, which can make them seem like signs of skin cancer.

Beyond newfound food cravings and morning sickness, pregnancy can also impact your appearance in unexpected ways, from nose-swelling to changes in your postpartum body.

One new development is a change in your skin. While dermatologists encourage us all to look for dark spots or mole coloration, that can be tricky during pregnancy, since some of the natural, harmless side effects can resemble skin cancer.

"There are a number of miscellaneous skin changes that occur in pregnancy," said Dr. Andrea Cambio, a board-certified dermatologist at Change Dermatology in Brentwood, Tennessee. "Due to all of the fluctuating hormones," she said you're likely to experience "darkening of your moles, the growth of new moles and skin tags, darkening of your areolae, and the development of a horizontal dark stripe on your tummy."

It's important to be vigilant about skin changes: While skin cancer like melanoma is rare overall, it's the most common form of skin cancer found among pregnant patients, according to Dr. Christina Boull, an assistant professor of dermatology at the University of Minnesota.

That being said, there are some ways to rule out potential skin cancer when observing natural changes in your skin color and texture during pregnancy.

Your skin can naturally darken during pregnancy, including any moles

Melasma, a type of hyperpigmentation, "typically presents as dark, lacy patches on the face," according to Cambio. She said it impacts about 70% of pregnant women, often forming on the cheeks, upper lip area, and forehead.

Cambio explained that during pregnancy, changes in estrogen and progesterone levels stimulate our bodies to produce more melanin when our skin is exposed to sunlight, potentially darkening moles as well.

However drastic this change may look, Boull noted that this increased pigmentation tends to go away after delivery and that there are also dermatological treatments available for any residual discoloration.

Key differences in the color, location, and shape of darker moles

One of the best ways to self-check for skin cancer like melanoma is to look for changes in the color, shape, size, or texture of your moles. But with conditions like melasma that can alter a mole's pigment, that can get tricky. Plus, Cambio said, it's "very common" to develop new moles during pregnancy.

Boull said to watch for "multiple colors within the mole, asymmetry, and developing irregular borders or edges." For instance, melanoma can present as gray or red spots on the mole.

Melasma, on the other hand, usually appears as a broad swath of light-brown or coffee-colored skin, so it can darken moles within that patch, but they shouldn't change much besides that.

It's also important to pay attention to where the mole is, said Boull.

Melasma patches are often symmetrical — you might have them on both cheeks, for example, and most often on the face rather than other parts of the body like the forearms. Melanoma, on the other hand, can occur in any part of the body and usually develops in a small area.

You can safely get a skin biopsy when you're pregnant

"To the untrained eye, it can sometimes be difficult to differentiate" a serious condition like melanoma from naturally occurring pregnancy changes, said Cambio. If you're still unsure, it's best to see a dermatologist right away.

According to Boull, melanoma diagnoses tend to be delayed in pregnant women, and while there is no data available as to the cause, "it's speculated that maybe that there's a delay in wanting to do a skin biopsy" out of fear of how it can impact the pregnancy.

Skin biopsies are safe to perform during pregnancy, she said, and being proactive about getting an early melanoma diagnosis isn't just crucial for your health, but for your baby's, too: Melanoma can spread from the placenta to the fetus.

Even if you feel like you're preemptively worried, Cambio said "a visit to the dermatologist during pregnancy is a good way to be reassured of what's normal and expected," so you can get back to preparing for an exciting new chapter.