Dr. Shettles wrote a book called “How to Choose the Sex of Your Baby” where he gives instructions on how to choose the sex of your baby. An expert with over 50 years experience in IVF, he explains how the X and Y sperm are different.
To have a boy you need a sperm with the ‘Y’ chromosome, versus the “X’ chromosome. All female eggs contain the ‘X’ chromosome. When you combine two X’s you get a girl while and X with a Y, give you a boy.
The ‘Y’ sperm are smaller but swim faster, while the ‘X’ sperm are heartier and larger, but swim slower.
The size and speed of the sperm make all the difference when it comes to timing of ovulation. If the egg is already in the Fallopian tube, most likely the faster swimmers, the’ Y’ sperm will get there first and result in an ‘XY’ fertilization, giving you a male fetus.
If a woman has not ovulated yet, the quicker ‘Y’ sperm will swim up the Fallopian tubes, but will not find an egg, while the slower, larger ‘X’ sperm are still making their way. The acidity in the vagina and tubes create a hostile environment, and the longer the sperm stay inside there, the more they die off. The smaller ‘Y’ sperm die first, so that by the time an egg is ovulation, only the heartier ‘X’ sperm are alive, resulting in an ‘XX’ fertilization … a girl fetus.
So it all comes down to timing. Tracking your ovulation is key. Dr. Shettles advises obtaining from sex for 4-5 days before ovulation, which increases sperm count. Then have sex on the day of ovulation. Position also helps deposit the sperm deeper into the vagina. Doggy style is great for having a boy.
There are ovulation kits to help you track your ovulation, as well as tracking your morning morning temprature (BBT), cervical mucus and cervical position.