Traveling the world is awesome, but unless you have your own private jet a la Beyonce, it's fair to say that the process of getting from A to B isn't exactly a highlight of the trip. There's the obvious excitement of an in-flight drink, but if you're airbound for six hours or more, being confined to a rigidly upright seat with marginal legroom isn't going to inspire the best nap.
Enter: jet lag. We all know how much it messes up our sleep patterns, but have you ever thought about how much it could actually impact your menstrual cycle, too?
To help you take control of your cycle when travelling long haul, researchers at period-tracking app Clue have explained exactly why hopping on an 8-hour flight can have more of an impact on your period than you'd think.
1. It messes with your circadian rhythms.
You're probably thinking WTF are circadian rhythms right about now, but basically, they're the things that influence your body clock. Your menstrual cycle has a hormonal relationship with these rhythms, so they get thrown off when we travel across time zones and become exposed to light at different times of the day.
If you picture a spinning top moving in a big circle, each little spin of the top is the circadian rhythm, and each big circle is the menstrual cycle. If the spinning top gets out of balance, the size and shape of the big circle may change. The top also spins a little bit differently depending on where it is in the big circle.
2. Lack of sleep can lead to stress.
Symptoms of jet lag include trouble falling and staying asleep, daytime sleepiness, loss of concentration, fatigue, disorientation, decreased alertness, and digestive issues—all of which can disrupt your menstrual cycle—but a lack of sleep can also cause stress. Any stress on the body can mess with your hormones, which in turn will have an impact on your usual cycle.
3. Be careful traveling east.
You might think the further afield you travel, the worse your jet lag will be (it seems logical, anyway), but it's more to do with the direction in which you travel. Symptoms are usually stronger when traveling west to east, and can last over twice as long. This is because it's harder for your body to adjust to a shorter day, and you lose time going east. So that means traveling to Paris wouldn't be too bad, but you'd probably feel the effects when returning to Manila. Staying in Europe it is, then!
4. Try to stay put.
It takes time for your hormones to get back into balance when jumping time zones. But if you stay put, you'll probably be back to normal within a cycle or two. Longer-term changes can happen due to things like constant travel (if you're taking some time to travel around the world, a good tip is to go east to west!), sleep problems, and working a job with night shifts. Research has shown that even a small amount of dim, artificial light can trigger hormonal changes in the body, so put that iPhone away before bed.
What you can do to make a difference:
1. Expect changes.
If your period is late post-holiday, you may be concerned that your holiday romance may have created more than just happy memories, but try not to panic about pregnancy. Menstrual changes, within reason, are normal for a cycle or two. Unless your symptoms are severe or persistent, you're probably just fine.
2. Reconsider your fertile window.
Be aware that your ovulation is likely to be off. Whether you want to become or avoid becoming pregnant, expect your fertile days to be different from your normal ones and act accordingly.
Carry menstrual products even if you might not expect a period. We all have our preferred sanitary products, but remember that they may not be available in some countries—ie. tampons with applicators are not available in many places, so it's advisable to bring some along if you need them. It's also wise to pack your usual pain medications or other personal remedies.
4. Track it and carry on.
Tracking can be a great way to keep a record of your jet lag symptoms. But if a cycle (or two) is affected, be sure to exclude it from your Clue averages—that way it won't affect your regular predictions.
This article originally appeared on Cosmopolitan.co.uk. Minor edits have been made by the Cosmo.ph editors.