Mandy Moore Reveals She's Dealing with Pregnancy Melasma, Says the Condition 'Is the Pits'

Mandy Moore is dealing with a skin condition as she awaits the arrival of third child.

The This Is Us star, 40, revealed on her Instagram Stories that she has a skin condition called melasma, which developed during her third pregnancy, according to E! News. 

On June 30, Moore shared a photo of herself laying with her eyes closed while rubbing a Lyma Laser on her temple. The device is said to have "unrivaled results on signs of aging, wrinkles, rosacea, pigmentation, skin elasticity and scarring," per the company’s website.

"Pregnancy melasma is the pits," Moore wrote on the post. "I heard @lymalife can help.'

According to the Cleveland Clinic, melasma is a harmless skin condition that causes brown or blue-gray patches or "freckle-like spots" on the body. The markings most commonly appear on one’s cheeks, nose, chin, upper lip and forehead.

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The website states that the condition is common among pregnant people, with 15-20% of those expecting experiencing melasma during their pregnancy.

in May, Moore announced that she is expecting a baby girl with her husband Taylor Goldsmith in a joint post on Instagram. 

"Sometimes life imitates art. The third in our own Big Three coming soon," the couple captioned the post, referring to Moore’s onscreen children in her hit NBC show. 

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The couple also share two sons Augustus "Gus," 3, and Oscar "Ozzie," 19 months. 

Last month, Moore spoke with PEOPLE in an exclusive interview about how her current pregnancy is different from the previous two. The singer and actress said she’s "just chasing two wild toddlers" this time around. "So that's the biggest difference," she added.