Can Sex Positions Determine Baby's Gender?

Q. My wife and I are trying to have a baby girl, since we already have a son. Are there any special lovemaking positions that might increase our chances?

A. People have been trying to figure this one out for centuries, "but there are really no lovemaking positions that can influence the gender of your baby," says Jeffrey Steinberg, MD, director of the gender selection program at the Fertility Institutes in Los Angeles.

Unfortunately, we're still at the whim of Mother Nature when it comes to the sex of our babies, despite the many fab folklore methods: Eat meat and salty food to get a boy; splurge on desserts to get a girl. Make love standing up or when there's a quarter moon if you want a son, but stick to the missionary position and make love during a full moon for a daughter.

You can also check out a 700-year-old Chinese conception chart that tells women which dates will result in boy or girl conceptions, based on the mother's age and the month of conception. But there's no scientific evidence that any of this works.

Nonetheless, gender selection is big business. You may have noticed sex selection kits marketed via the Internet that guarantee results with douches, vitamins, or do-it-yourself artificial insemination kits. Not one of them has been sanctioned by science. The best-known book is by invitro-fertilization pioneer Landrum Shettles, MD, who first published a report in the 1960s on the distinctive characteristics of X-bearing (girl-producing) and Y-bearing (boy-producing) sperm, and compiled a series of noninvasive, low-tech family planning techniques.

For instance, the late Dr. Shettles advised couples seeking a son to have sex as close to ovulation as possible, because that's when a woman's vaginal and cervical fluids tend to be the most alkaline, a condition that makes conception most favorable for the less-hearty Y sperm. However, a study published by the New England Journal of Medicine reported that there was no relationship between the timing of intercourse and the baby's gender.

"There's really not much you can do at home to choose your baby's gender," sums up Dr. Steinberg. If you're really determined to have a girl, outside the bedroom there are two high-tech medical procedures involving sperm or embryo sorting that hold more promise, but their ethics are being debated on all fronts.

Holly Robinson lives with her husband and their five kids outside of Boston.

Originally published in American Baby magazine, December 2004.