If you are one of the many women in the drop zone right now, you can count on one date as the most likely to appear on your baby’s birth certificate: February 14th.

Yup, that’s right, according to researchers, more babies arrive on Valentine’s Day than the days before or after.

Here’s the crazy part – your brain might subconsciously choose this date for you!

Babies born on Valentine’s Day vs. Halloween

Researchers from the Yale University School of Public Health crunched over a decade’s worth of birth data to compare the number of births on and around Valentine’s Day with its holiday opposite: Halloween. The goal of the study was to test the idea that women will avoid giving birth on days with negative associations (Halloween = witches, ghosts, and death) but will aim to give birth on days with positive associations (Valentine’s Day = hearts, love, and baby-faced cherubs).

The results? October 31st show a significant dip – there were 11.3% fewer births on Halloween – while Valentine’s Day shows a spike – an average of 5% more births on that day[1].

The results are not terribly surprising given that we live in a world where we, the hospital and the doctors have some control over our birth dates. Various studies have shown that “preference” for specific dates drives both increases and decrease in interventions (c-section, induction). For example, a study on Chinese Americans showed that this group of women avoided the unlucky number 4 (4th, 14th, 24th of each month) and chose to have babies on the lucky number 8 (8th, 18th, 28th of each month)[2].  Australians avoid February 29th and April 1st[3] as do Japanese women[4]. The latter group also shows an increase in births in the days leading up to New Year’s due to “institutional reasons”. Perhaps doctors wanted to take January 1st off?

But here’s the thing with Valentine’s Day and Halloween babies…

Spontaneous births increase on Valentine’s Day and decrease on Halloween.

Sure c-section rates and elective inductions change most significantly, but births with zero intervention also spike or dip down depending on the holiday.  There were 3.6% more spontaneous births on February 14th and 5.3% fewer spontaneous births on October 31st when compared to two weeks before and after. Do those images of love and cherubs and vs. witches and ghosts affect how our brain signals the body to initiate labor? Maybe…

“The study raises the possibility that the assumption underlying the term ‘spontaneous birth’, namely, that births are outside the control of pregnant women, is erroneous. We know that hormones control birth timing, and mothers do often express a desire to give birth on a certain day. But the process that allows those thoughts to potentially impact the timing, we don’t know.”

– Dr. Rebecca Levy, lead researcher as told to The New Scientist.

References

1. Levy, B. R., Chung, P. H. & Slade, M. D. Influence of Valentine’s Day and Halloween on Birth Timing. Soc. Sci. Med. 73, 1246–1248 (2011).
2. Almond, D., Chee, C. P., Sviatschi, M. M. & Zhong, N. Auspicious birth dates among Chinese in California. Econ. Hum. Biol. 18, 153–159 (2015).
3. Gans, J. S. & Leigh, A. Bargaining Over Labour: Do Patients Have Any Power? Econ. Rec. 88, 182–194 (2011).
4. Takahashi, M. The distinctive characteristics of the hourly distribution of live births on specific days in Japan. Environ. Health Prev. Med. 21, 501–522 (2016).