Nails: Manis and pedis are fine, but bring your instruments from home (to reduce infection risk), and "apply nail polish in a well-ventilated area so you don't inhale the fumes," suggests Joel Evans, M.D., assistant clinical professor of ob-gyn at Albert Einstein College of Medicine in the Bronx, New York. Say no to foot massages, which can stimulate fetal activity and contractions.
Hair: "There's no major data suggesting that hair coloring increases birth defects or miscarriage," says Joshua A. Copel, M.D., professor of obstetrics and gynecology at Yale University. But schedule peroxide pick-me-ups after your first trimester. By then, your baby's organs have formed.
Skin: Avoid Retin-A other topical retinoids, and salicylic acid. Creams with glycolic or azelaic acid are fine.
Bejeweled belly? Alas, the journey to momhood may lead to naked naveldom. Docs recommend the removal of belly button piercings by the six-month mark (your stretching stomach may well agree). If you've gotta keep the barbell, get one with a flexible shaft (at pregnancypiercings.com)