If you’re expecting a baby this month you’ve got plenty of company. As many elementary school teachers have no doubt noticed, the first month of the school year is also the most popular month for birthdays in America.

The trend was first unearthed by data journalist Matt Stiles, who combed through birth stats from from the U.S. National Center for Health Statistics and the U.S. Social Security Administration collected between 1994 and 2014. He found that, statistically, mid-September is the most popular time to give birth—by far.

According to Stiles, the most common American birthdays fall on September 9, 19 and 12, respectively. Beyond that, nine out of the 10 most popular birth dates for babies in the United States are celebrated in September.

Just why are maternity wards so busy this time of year? The reasons aren’t as clear as the data Stiles drummed up, but the calendar does provide some pretty good clues: Turn back nine months from September 9 and we’re looking at December 17, a popular day for post-Christmas party canoodling and fireside snuggles. The conception date for a September 19 birth would be December 27, a day often reserved for relaxing with one’s significant other after chaotic Christmas schedules.

september is by far the most popular birthday monthand heres why 0

Studies show the popularity of Christmastime conceptions might have as much to do with biology as holiday vacation time. And, interestingly, Stiles found the days most popular for baby-making aren’t popular for baby-having.

“The least-common birthdays in this dataset were Christmas Eve, Christmas and New Year’s Day,” he notes. “Dates around Thanksgiving aren’t as common. July 4 is also at the bottom of the list.”

Obviously some of the reasons for the Christmas slump are due to medical interventions—as inductions and c-sections are less likely to be scheduled on December 25. Apparently OBs don’t mind working on Valentine’s Day, though, because that’s one holiday with a relatively high birth rate.

As popular as it is (the sixty-third most common birth date) V-day can’t touch September 9 when it comes to the amount of love entering the world. Maybe we should add another holiday to the calendar to celebrate this yearly baby boom? We could christen September 9 “Baby Day” and everyone could take the day off—although stats show that may lead to the rise of another popular birth date. What’s the date nine months after September 9?

[Originally published September 4, 2017]

Preparing for a September baby? We’ve got the goods you need in the Motherly Shop!

Belly and Bag pre-packed birth bag

Belly and Bag pre-packed hospital bag

You’ve got plenty of other jobs to do right now, mama. Cross birth bag packing off your list and leave it to the pros instead! The pre-packed birth bag from Belly and Bag includes everything from nipple balm to a universal phone charger and comes packed and ready for go time.




Echo Art Bindery baby book


This keepsake baby book is so gorgeous it will be hard to forget to fill it out throughout the year. The best part? The sweet prompts that help capture memories you’d otherwise forget.




Bebe au Lait monthly milestone set

Bebe au Lait monthly milestone set

The first year is marked by unbelievable growth. Celebrate each month of their progress with these sweet, minimalist wood milestone discs. Set up your monthly photo shoot with their favorite blanket, toy or lovey and snap away, mama!




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