The lowdown on whether you can really sway the odds.
Jean and Robert Krak, of McMurray, Pennsylvania, were the proud parents of three boys, ages 7, 6, and 2. "We wanted a fourth child, and we wondered if there was any way to slant the odds in favor of having a girl -- to have the experience of raising a daughter," Jean recalls.
An obstetrician gave her instructions for timing fertilization, intercourse positions, and using a douche to increase her chances of having a girl. "He made no promises but said this technique had worked for others," says Jean. "We figured we'd try it, knowing that God still had the ultimate veto power." The family now includes 2-year-old Angela Marie.
Strategies for conceiving a child of a particular sex have been around for centuries. The Talmud, a major book of Jewish law, says that if a wife's orgasm precedes her husband's, the baby will be a boy. In the 13th century, a Chinese scientist created a chart that a woman could use to match her age to the month of the year when she was likely to conceive a boy or girl; some people still think it works (Chinese Astrology).
Age-old advice ranges from the ridiculous (a German folktale suggests placing a wooden spoon under your bed to conceive a girl) to the theoretically plausible (a man drinking coffee 30 minutes before intercourse to increase the speed of boy-producing sperm).
Low-tech methods of conceiving a specific sex are worth a try, but they're hardly guaranteed. "Couples should aim for having a healthy child; then, if they can increase their odds for a child of a particular sex, why not?" says J. Martin Young, M.D., a clinical assistant professor of pediatrics at Texas Tech University Medical School, in Amarillo, and author of How to Have a Girl and How to Have a Boy (Young Ideas Publishing). "As long as they'll be happy regardless of whether they have a boy or a girl, the outcome should be good."
Boosting the Speed of Sperm
Eggs and sperm carry chromosomes, the building-blocks of DNA that contain our genes. All eggs and half of all sperm contain X chromosomes; the other half of sperm have Y chromosomes. If a Y-carrying sperm fertilizes an egg, the baby will be male; if an X-bearing sperm gets there first, the baby will be female. "Recent evidence suggests that the Y-carrying sperm are slightly lighter than the X-carrying sperm, so they're faster swimmers," says Masood Khatamee, M.D., a clinical professor of obstetrics and gynecology at New York University School of Medicine and director of the Fertility Research Foundation, in New York City. This difference underlies the strategies for at-home sex selection.
Nearly 30 years ago, Landrum B. Shettles, M.D., Ph.D., a researcher at the Fertility Research Foundation published How to Choose the Sex of Your Baby (Doubleday). The book has sold more than 1 million copies, and many couples vouch for its success. The main theory behind Shettles's technique: Boy-producing sperm are faster than girl-producing sperm, but they can't survive in an acidic atmosphere as long as girl-producing sperm can.
Until a day or so before ovulation, the vagina and cervix tend to be slightly acidic, and girl-bearing sperm tend to have more staying power. So, says Dr. Shettles, if you want to conceive a girl, have intercourse daily from the time menstrual bleeding ceases until two days before ovulation. Then abstain until well after ovulation. Have sex in the missionary position (fact-to-face with the man on top) to allow for a shallow deposit of sperm that has to swim through the acidic vaginal secretions. Also, try not to have an orgasm, since it increases alkaline secretions, favoring boy-producing sperm, says Dr. Shettles.
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."
Copyright © 2001 Laura Flynn McCarthy. Reprinted with permission from the Spring 2001 issue of Expecting magazine; Spring/01.
All content here, including advice from doctors and other health professionals, should be considered as opinion only. Always seek the direct advice of your own doctor in connection with any questions or issues you may have regarding your own health or the health of others.