Once upon a time, which was before about 35 years ago, no one could predict the sex of the baby until the baby was born. And no one had any method of guaranteeing or even of just increasing the chances of having a baby boy rather than a baby girl, or vice versa.
The truth is that men have all real control over determining the sex of a child. They produce sperm with either an X chromosome or a Y chromosome. If the sperm carrying the X chromosome fertilized the egg, you get a girl. If the sperm with a Y chromosome gets to that finish line first, you get a boy. It is always the man’s sperm that determines the sex of the baby. The egg (and the woman who produced it and who carries the baby to term) have little to do with determining the sex of the child.
But throughout history and across cultures, there have been times when having a baby of one gender was more desirable than a baby of the opposite sex. For most of history and in many cultures, the preferred gender was male. Sadly, baby girls have rarely been in strong demand. Even sadder, baby boys are still prized more than girls in several areas of the world.
Because families or societies wanted a baby of one gender over the other, there are dozens of folk beliefs or practices that were said to be the sure thing for producing the desired baby. Some methods made more sense than others, and many contradicted each other, but all have been tried at one time or another.
Certain sex positions were said to produce a boy. The missionary position, with the woman flat on her back below the man, was one recommendation. Conversely, another recommended position for a boy was “doggy style,” with the woman on her hands and knees and the man entering her from behind. (And some folk methods disagreed and said missionary was better for begetting girls. See what we mean about contradicting advice?)
Women were told to eat lots of vegetables, especially lots of green, leafy vegetables like spinach and broccoli and to cut out the salt, if they wanted a girl. Red meat and salty foods were the choice if they wanted a boy. Men have been told to drink a cup of strong coffee an hour before intercourse to speed up the sperm carrying a Y chromosome.
Another idea that had some currency for a while was changing the pH of the vagina. Using a vinegar douche was said to help the sperm that produce girls while using a douche with some baking soda in it was said to produce boys.
People were told to have sex during the full moon if they wanted a boy. A study done in India even had some statistics to back this idea up. “It was observed that 42 wives who were conceived within 24 hours of ovulation at full moon gave birth of 40 male and 2 female babies. On the other hand, 40 women conceived on the day of ovulation 3 days prior to full moon gave birth of 13 male and 27 female babies.”
Those numbers look impressive, but the moon may not have had as much of an influence here as the day of ovulation. One book on conceiving the baby of the gender you want strongly advises that, for a boy, couples should have sex as close to when the woman ovulates as possible. For a girl, have sex a few days before ovulation, according to the author
Why was it so important what sex your baby will be when it is always a 50-50 proposition? Women have been punished or even killed when they were told they must produce a boy and didn’t. Queens were divorced by their royal husbands when they did not provide a male heir to the throne. Even today, in countries where a family must provide a dowry for daughters, the mother of girls might be seriously punished.
This societal pressure and even danger for mothers who only had daughters is why so many old wives’ tales or folk treatments came into existence, even if they didn’t really work.