laughIn many countries, it’s an informal custom to play April Fool’s Day pranks on the first day of April.

You’ll probably see April Fool’s jokes pop up everywhere. For instance, my husband, a guitar player, was just sent a video demonstrating a new piece of equipment that lets you play the guitar with just one hand–which took him a minute or so to realize was just an April Fool’s prank. And I just noticed that Bing.com veered toward the adorable for their April Fool’s joke today.

Depending on where you are in your cycle, you’re more or less likely to fall for pranks you see online or are played upon you by your partner, friend, co-worker, train conductor or anyone else you come in contact with today.

So, before you fall for a good yarn today, check your menstrual cycle calendar to see where you are in your cycle:

If you’re in the first half of your cycle, you’re more likely to fall for April Fool’s Day pranks. The reason? Rising estrogen is boosting brain chemicals that elevate your mood, which makes you look at things with a less critical eye and accept what people are telling you at face value. After all, with your estrogen-fueled optimistic mindset, you’re convinced no one would want to pull a fast one on you or make you the butt of their April Fool’s Day joke!

The good news? If (okay, when) someone pulls a prank on you today, rising estrogen is helping you find the humor in it–and even think of ways to prank the person back!

If you’re in the second half of your cycle, you’re less likely to fall for April Fool’s Day pranks. That’s because a lower level of estrogen is bringing down mood-elevating brain chemicals, so you’re looking at the world with a more suspicious eye. Plus, play-it-safe progesterone is on the scene during these two weeks of your cycle–and this hormone prompts you to look out for things that can jeopardize your safety, like a fake snake someone put in your desk drawer.

On the downside, woe to anyone who’s caught trying to prank you today. Your hormones in these two weeks of your cycle make you less likely to find the charm in being made the target of someone’s April Fool’s Day joke. So, the pranksters better be really good at hiding their tracks!