Loola said:They say that the female sperm is slower than the male, so if you only BD about 2 days before ovulation you are more likely to have a girl. The boy sperm are faster and therefore you should BD on the day before and the day of ovulation to conceive a boy. Obviously I have no proof of this, but it does make sense.
Chrissy1 said:the taking charge of your fertility book says that the female spermies can survive longer inside you (because they're tougher of course) but they swim slower! However the boy spermies swin faster but they are a bit weak and feeble and don't survive as well as the femal ones.
Theory is that if you want a girl make sure you BD a couple of days before you OV becacue by that time all the boy ones will be gone and the girl ones will be just about getting to where they need to be (always fashionably late!!)
If you want a boy you should do it on the day of OV or the day after so that they are the first ones to reach the egg.
it's just a theory but if it's true I suppose it would work.
If you do it in on all the days running up to OV then i suppose it's just luck on which one gets in first.