photo from Borders
Forget everything you learned in biology about how the chromosomes in sperm determine the sex of a baby. There's new research out all the time saying that there are various other factors that influence whether you will conceive a boy or a girl. Last year, a study in Scientific American found that women who had boys ate more cereal than women who had girls.
And there are old customs people used to influence the sex of the baby, such as tying up one of the man's testicles or putting certain objects under the bed. There's even medical advice on how to conceive a baby in the gender of your choice. In his book How to Choose the Sex of Your Baby, Dr. Landrum Shettles recommends having sex once a day in the missionary position without having an orgasm if you want a girl (orgasms make the vagina more alkaline, which is not favorable for baby girls).
And now brand-new research shows that girls are more likely to be born in hotter climates. Scientists say this may be because climate changes sperm quality or that there may be an evolutionary advantage to having more girls if you live by the equator.
You're also more likely to have a girl during hard times of extreme environmental stress. For example, more girls than boys are born during wars. Scientists theorize that this is because female fetuses are less fragile than male fetuses, which are more susceptible to the effects of a pregnant woman's environment.
There is an exception to the "hard times" rule. According to Dr. Bill James of University College London, who has spent his career studying sex ratio patterns, women who carry the hepatitis B virus and women who have pre-eclampsia in pregnancy are more likely to have boys.
So there you have it. If you want a girl, wait for a heat wave, and then get busy.
Did you conceive your baby in summer or in a hot climate? Did you have a girl? Did you have pre-eclampsia and a boy?