*WARNING: MATURE AUDIENCE ONLY* I have tried this method and it worked for me (both times)! Thought i was the only one who knew about it but apparently its common knowledge already, just the all the gynecologists don't want to discuss it. They say "don't play God" etc. Principles aside, here is what extracted from the book "How to Choose the Sex of Your Baby by Landrum B. Shettles". You can get her book here . Fundamentals The male Y-sperm are said to: Swim faster Die faster Are smaller (don't see how this matters) The female X-sperm are said to: Swims slow (like female drivers) More hardy, can survive better inside the woman Are bigger (erm yeah, so?) Boy: Do it Doggie style Deeper penetration inserts the male sperm closer to the egg, this allows the male sperm to reach the egg in a shorter amount of time. Their exposure to the 'harmful environment is reduced. Females should achieve Orgasm Females orgasm makes environmen...