4 common pregnancy skin issues

Here are a few of the most common—and a few extreme—conditions you may see reflected in the mirror.

1. Acne “With my first pregnancy, my once-good skin exploded,” says Oakville, Ont., mom Glenda Farnsworth. Pregnancy acne can cover the face, back and shoulders and appears when hormone surges send oil production into overdrive. It tends to clear up when hormones level off, but this varies for each woman. “Thankfully, my breakouts stopped at 16 weeks,” says Farnsworth.

Those with bad acne might be eager to treat it, but Anatoli Freiman, medical director of the Toronto Dermatology Centre, advises caution. Products containing retinoids and salicylic acid are totally off-limits, while medications with benzoyl peroxide or glycolic acid can sometimes be considered safe in low doses. Consult your doctor or a dermatologist before treating your acne, says Freiman.

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2. Linea nigra and melasma Hormone fluctuations trigger an increase in melanin production (the pigment that gives skin its colour), which can cause a line to appear from your belly button to pubic bone, called the linea nigra. Don’t panic: It should fade on its own postpartum.

Hormone spikes can also cause melasma, known as the mask of pregnancy because dark patches appear around the upper lip, nose, cheekbones and forehead. It’s more common in young women, those with a family history and those with dark complexions, and it tends to intensify with sun exposure (wear SPF daily) and with each pregnancy. “For many women, dark patches fade a few months after delivery, but for some it never totally goes away,” says Freiman. For severe cases, microdermabrasion treatments with a dermatologist or at-home serums or peels with vitamin A or retinol can help fade dark patches, but for safety reasons, these treatments should only be done postpartum and post-breastfeeding.

3. Pruritic urticarial papules and plaques of pregnancy (PUPPP) “It started with a small rash on my arm at about 37 weeks, but within days it spread from my shoulders to the soles of my feet,” says Sneha Varma Landucci, a mom of two in Lancaster, Ont. It was her first pregnancy, and a severe case of PUPPP, an itchy rash that isn’t harmful to Mom or baby but can be very stubborn. Varma Landucci was seriously uncomfortable, and the oatmeal baths her doctor recommended didn’t help much. Her constant scratching left sores all over her legs. “My OB said the only way to make it stop was to deliver the baby.” But even after having her baby, the rash lingered on her arms, stomach and feet (the most common places for PUPPP) for three more months before disappearing. Experts don’t know what causes PUPPP—some theories point to genetics, others think it’s a kind of allergic reaction to the damaged tissue from stretching skin. It’s more common in first-time moms and with those carrying multiples, but only occurs in about one percent of pregnancies.

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4. Obstetric cholestasis (OC) Another very rare condition marked by intense itching—typically on the palms and soles, but without a rash—and occasionally jaundice and nausea, OC usually shows up in the third trimester. It’s caused by impaired liver function, when the normal flow of bile from the liver to the intestines slows—some experts think it’s due to peaking hormones, but genetics may play a role, too—and acids start to build up in the bloodstream. It doesn’t pose a risk to Mom or baby, but OC can affect the way your blood clots, and it does increase the risk of preterm birth, so extra monitoring is done via blood tests, ultrasound and heartbeat checks. The only cure for OC is birth, but your doctor may prescribe some topical creams to ease the itch in the meantime.

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Wait, there’s more Other skin issues that may come up: stretch marks; swelling of blood vessels, which can lead to spider and varicose veins; excessive (and unwanted!) hair growth and skin tags, which are pretty harmless. Like pregnancy itself, most conditions are temporary and ease up once the baby appears.

A version of this article appeared in the January 2015 issue with the headline "Skin woes," p. 51.