How to Influence the Sex of a Baby

On average, you have slightly more than a 50 percent chance of conceiving a boy and a slightly less than a 50 percent chance of conceiving a girl, according to the Centers for Disease Control and Prevention. The same research reveals that older moms (over 40) have closer to a 50/50 chance of having a boy or girl and that the more children you have, the more likely you are to have the same number of boys and girls. If you have a house full of rough-and-tumble boys or darling girls who have you tripping over dress-up clothes, you may feel the need to add a child to balance out the family dynamics. You don’t have to leave it completely up to chance. There is a scientifically based way, called Shettle’s method, that helps influence the sex of the baby, says Toni Weschler in “Taking Charge of Your Fertility.”

Step 1

Determine the exact day that you are likely to ovulate. You can do this by recording and charting your morning waking body temperature every day for several months and using ovulation detection tests. By recording the rise in temperature that occurs the day after ovulation with the positive results of the tests, you will have a good idea of your regular ovulation day.

Step 2

Have intercourse on the day before or the day of ovulation to increase your chances of having a boy. The male sperm are smaller, faster and more likely to get to the egg first. Since the egg only survives for about 24 hours, this timing gives the female sperm less of a chance of ever making it to the egg.

Step 3

Have intercourse two to five days before ovulation. Sperm survive for up five days. This gives the larger and slower female sperm time to reach the egg. However, trying for a girl does have less success than for boys since the boy sperm are already waiting for the egg by the time the girls get there.