Named for its creator, Dr. Landrum Shettles, the Shettles Method attempts to stack the odds for having a boy or a girl. Here’s how it works: There are basically two types of sperm, those that carry the X chromosomes and those with the Y. A mother’s egg is always an X. If an X-carrying sperm fertilizes your egg first, you’ll have a girl. If the Y is the winner, you’ll have a boy. Shettles based his theories on the fact that X-bearing sperm survive longer in the cervical environment and are a little slower than the Y swimmers. But while the Y sperm are faster, they’re also a little more delicate. To have a girl, goes Shettles’ theory, you should plan on having sex two to three days before ovulation, which means the Y sperm will die off first and leave the X-ers ripe for fertilization. (Note this is the opposite plan of the Whelan Method, which says you should have sex on the early side to have a boy because they’ll hang around longer.) He also maintained you should avoid orgasms because it makes the vagina a less happy place for the X sperm, which like an acidic environment (that’s no fun!). To have a boy, on the other hand, the method says have sex as close to ovulation as possible and use sexual positions with deep penetration to help those speedy (but less strong) Y sperm reach their mark. Unfortunately, although Shettles himself claimed success, no one else has been able to show these methods will enhance your chances of having a boy or girl one way or the other. Your best strategy might just be to time your intercourse around your ovulation and hope for a happy, healthy baby, no matter the gender.
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