For a boy, reverse the advice. Have sex on the day of ovulation or right before or after, when vaginal secretions and cervical mucus are most alkaline. Deep penetration, such as with your husband on his knees behind you, helps deposit the Y-bearing sperm near the opening of the cervix. Douching with baking soda and water can enhance vaginal alkalinity. Having an orgasm at the same time as or just before your husband also enhances alkalinity and helps transport sperm into the cervix, where the secretions are more favorable to boy-producing sperm.
Dr. Shettles claims a 75 percent success rate when all of his steps are followed exactly. But while many women swear by his technique, the medical community is less enthusiastic. "What Dr. Shettles proposes seems to make sense," says Dr. Khatamee. "But when put to the test, his methods haven't held up."
The Importance of Timing
Some research has found that Dr. Shettles's techniques may increase a couple's chances of having the opposite sex of the one they want. One study found that couples who followed his advice had only a 39 percent chance of conceiving the gender of their choice. That's less than the 50-percent chance they'd have if they let nature take its course.
Dr. Young's advice contradicts that of Dr. Shettles. "My method is based on the fact that at least five studies, some of which tested Dr. Shettles's theory, have found that girls are usually conceived right at ovulation and that boys are conceived four to six days before and two days after ovulation," says Dr. Young.
His recommendations: Have sex within 24 hours of ovulation to increase your chances of conceiving a girl to about 55 to 60 percent; to increase your odds of conceiving a boy to about 60 to 65 percent, have sex four to six days preceding ovulation and then abstain. The woman should remain still for 20 minutes after intercourse to increase the survival of all sperm and the chance of fertilization. In addition, use a baking soda douche.
You can try Dr. Shettles's time-honored technique or Dr. Young's more modern approach -- or you could test the old wives' tales in How to Make a Boy or Girl Baby! by Shelly Lavigne (Dell). Romanian folklore, for example, says that if you want a boy, sprinkle salt in your bed prior to intercourse. Want a girl? Make love on a rainy day. "In the end, once your gaze into your newborn's eyes, it won't matter what the sex of your baby is," says Lavigne, a mother of two. "You'll already be hopelessly in love."
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