What's going on: The levels of estrogen, progesterone, and androgens (male hormones produced by fetuses of either sex) may enhance your libido; an increased blood supply pumps through your erogenous zones; and intensified vaginal secretions may help lube things up. The happy result: hot second-trimester sex. (Some women may be too tired to get much pleasure out of lovemaking during the early months and feel too unwieldy to maneuver later on.) Some mothers-to-be even luck into multiple orgasms.
According to Iffath Hoskins, M.D., chief of obstetrics at New York University Downtown Hospital, in New York City, all that extra blood flow can result in vulvar varicosities and hemorrhoids (essentially, varicose veins of the vagina, vulva, and anus). And hormonal changes alter vaginal flora and make your vaginal area a breeding ground for yeast infections, she says.
What to do about it: As long as your pregnancy isn't high risk, go ahead and enjoy sex as often as you can -- soon enough, a wailing newborn and extreme sleep deprivation will make those sexy interludes seem like they happened in another lifetime. To soothe hemorrhoids and vulvar varicosities, make liberal use of ice packs and witch hazel compresses. See your doctor if these uncomfortable veins don't subside after delivery. If you suspect a vaginal infection, ask your obstetrician to recommend a safe treatment. Women prone to yeast infections may be able to head them off by eating yogurt with live acidophilus cultures (an easy way to pack in extra calcium, too).