If you’d like your baby’s date of birth to be Nov. 11, 2011 — that’s 11/11/11, in case you didn’t notice — you’d better plan on getting busy Friday.

That helpful reminder comes to you courtesy of AOL News, which points out that Friday is prime baby-making time for women with a regular 28-day menstrual cycle.

Even if you and your partner did conceive on Friday, there’s no guarantee the baby would be born on Nov. 11. It’s just more likely, assuming a 40-week gestation period.

Of course, babies rarely arrive on their due date.

“Most times, it’s a day or two on either side of the due date,” obstetrician Joe Hill told AOL News. “Only the baby knows for sure.”

Women under the age of 35 have a one in five chance of giving birth on a specific day, according to the article. Older mothers have a 10 percent chance.

This should go without saying, but I’ll say it anyway: If you have your heart set on having an 11/11/11 baby for some reason, this is your only chance. The next time the calendar aligns like this will be Nov. 11, 2111.

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