What to Expect When You're Expecting a Valentine

Sometimes I find a certain rhythmic method of collecting interesting data. Last week, I was looking at birth rate stats for the post about 2016 deaths, and it made me wonder whether certain events correlate to the idea that you might, in fact, be expecting. While there are numerous search terms that might relate to it, I went with search demand for [pregnancy test] for reasons that will be obvious. 

Consider the following graph, which shows a distinct annual spike in US search demand:

US search demand for [pregnancy test], 2012-2017.

While it's not easy to see exactly when it occurs on the graph, during every year I looked at, there's a large spike in search demand for [pregnancy test] around the last week of March or first week of April, or roughly six weeks after Valentine's Day. Here's the demand curve for [pregnancy test] and [valentine's day gift] side by side for reference:

US-based demand for [pregnancy test] and [valentine's day gift], last five years.

(This is US data only. I tried to find a similar curve in other countries, but nothing stood out.)

This correlation is intriguing, of course, but it's not conclusive. You could almost as easily correlate it to the Super Bowl or even St. Patrick's Day, although two weeks after the latter seems a bit early to be concerned.

Happy Valentine's Day. Be careful out there.