Summer after sunny summer, you've been the model of sun protection. Right? But now that you're pregnant (congrats!), shielding yourself from the sun's harmful ultraviolet, or UV, rays is more important than ever. Your body's pigment-producing cells (called melanocytes) kick into overdrive during pregnancy, making your skin more susceptible to UV-induced discoloration. Plus, while sun exposure doesn't directly affect your bun in the oven, sunburns can crank up that oven's temperatures, says Joanne Stone, M.D., director of maternal fetal medicine at The Mount Sinai Hospital in New York City. (Elevated core temperatures during pregnancy have been linked to birth defects.) Follow these sun safety tips to protect your body and your baby.
Know Your Numbers
Don't let a super-high SPF give you a false sense of security: SPF 15 blocks 93 percent of UVB rays; SPF 30 blocks 97 percent; and SPF 50 blocks 98 percent, according to the Skin Cancer Foundation. That means, SPF 100 isn't exactly twice as good as SPF 50. A good rule-of-thumb? Use at least SPF 30, reapplying at least every two hours (more often if you're in and out of water). Reapplying is what really makes the skin-saving difference, says Dr. Stone.
Always opt for broad-spectrum sunscreens, which offer protection against UVA rays, in addition to UVB rays, both of which can cause skin cancer. Plus, UVA rays are infamous for causing discoloration (common during pregnancy), according to the American Academy of Dermatology.
Sunscreens fall into two categories: physical sunscreens (which reflect UV rays using titanium dioxide or zinc oxide) and chemical sunscreens (which absorb UV rays using ingredients like oxybenzone; see slide 5). Even though people have expressed concern about the tiny "nanoparticles" in physical sunscreens, the European Union's Nanoderm Project and seperate research conducted by the FDA found that nano titanium dioxide particles pose no significant risk of penetrating the skin: "We believe that zinc oxide and titanium dioxide are among the best choices on the American market," says the Environmental Working Group's 2014 Guide to Sunscreens.
Rub, Don't Spray
The International Agency for Research on Carcinogens has classified titanium dioxide as a "possible carcinogen" when inhaled in high doses. That's why the Environmental Working Group (EWG) recommends avoiding sprays. "They also make it easy to apply too little or to miss a spot," says Sonya Lunder, MPH, senior analyst with the EWG. Stick with tried-and-true lotions to best protect you and your little one.
Kick This Chemical
Make sure your sunscreen doesn't list oxybenzone on the back. The chemical, which readily absorbs into your skin, has been linked to low birth weights—a risk factor for future coronary heart disease, hypertension, type 2 diabetes, and other diseases. It's also known to interfere with the body's hormones, which may cause developmental problems in unborn babies.
Opt for Oil-Free
Pregnancy hormones can cause acne, and slathering your face with oil-containing sunscreens can make breakouts worse, says Dr. Stone. She suggests using an oil-free and non-comedogenic (meaning it won't clog pores) formula on your face—if not on your entire body.
Related: Get Rid of Pregnancy Acne