6 Reasons Your Period Is Late (Other Than Pregnancy)

Photographed by Alexandra Gavillet.
Periods may be annoying, but at least they're predictable — sort of. If yours is a little delayed this cycle, and you're not trying to get pregnant right now, your first instinct is probably to freak out a bit. But don't.
There are actually many things that can delay your period that have nothing to do with being pregnant. For instance, many medications list delayed periods as a side effect, especially psychiatric drugs that can elevate your levels of prolactin. (This hormone is produced in low levels by your body at all times, but it becomes elevated during and right after pregnancy to help you produce breast milk.) "Usually women get told [about the possibility] because it’s a relatively common side effect" of these medications, explains Raquel B. Dardik, MD at the NYU Langone Medical Center. "So it’s not usually much of a surprise."
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However, other culprits might seem to come out of nowhere.
Before we get to those, we need to quickly mention a few caveats: in most of the cases to follow, we're talking about just one late period. If this has happened to you three or more times in a row, that's a sign that you should check in with your doctor to make sure you're not dealing with irregular periods, which can be caused by more pressing matters like polycystic ovary syndrome (PCOS) or fibroids (benign uterine tumors). Also, if your period is over a week late and you know you've had unprotected sex this cycle, it's time to take a pregnancy test.
Click through to see five other possible reasons why your period might be tardy this month.
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Photographed by Alexandra Gavillet.
1. Stress
One of the most common causes of a later period is, unfortunately, stress. That's because when you're stressed, your level of the hormone cortisol increases. And, says Dr. Dardik, "that can delay ovulation or suppress it altogether."

Of course, "that's sort of a double whammy," Dr. Dardik says, because you're already stressed and being worried about a missed period isn't exactly going to help that situation. So if you've been through some trying times or experienced heightened anxiety recently, give yourself a break and be patient.
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Photographed by Tayler Smith.
2. Birth Control Pills
"It's hard to reassure somebody that not getting [a] period doesn’t mean they're pregnant when they’re on the pill," Dr. Dardik says. "That’s the most common phone call that I will get."

However, the truth is that hormonal birth control is the other major cause of period weirdness. Dr. Dardik explains that the dose of hormones we get with the pill is very low these days. That causes the endometrial lining to grow very thin, which is a good thing because it makes your period very light. But the pill can also make it too light, even to the point that there's really nothing to shed — and no period to have.

But that's not a huge health worry because, as we wrote previously, you really don't need a period anyway.
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Photographed by Tayler Smith.
3. Emergency Contraception
"Plan B is a big dose of [synthetic] progesterone," Dr. Dardik says. That hormone surge prevents ovulation and it "can delay your period for up to a week," she explains. But if your period is at least a week late, this is definitely a situation in which you're going to want to take a pregnancy test to calm your mind.
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Photographed by Tayler Smith.
4. Your Thyroid
The thyroid is a little butterfly-shaped gland that sits in your neck. It's here that your body produces hormones that affect many bodily processes, including your period.

If your thyroid is overactive (a.k.a hyperthyroidism), you're more likely to have lighter periods. And with hypothyroidism (an underactive thyroid) your periods may be especially heavy. But both conditions can cause irregular cycles that may end up delaying or skipping your period.

Thyroid issues also tend to affect your energy levels, moods, and even your heart rate. So if your thyroid is at the root of your period issue, you probably also have other symptoms. Although thyroid conditions may be particularly confusing to diagnose, treatment is usually quite straightforward. Check in with your doctor if you think this might be your issue.
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Photographed by Alexandra Gavillet.
5. Extreme Circumstances
Stress certainly counts in this category. But if you've been through other extreme situations recently, your period may be out of whack.
That could include life changes like major surgery or significant weight loss associated with an eating disorder, Dr. Dardik says. It could also include a traumatic experience, such as sexual assault, a loss of a loved one, or a really bad car accident. So if you've been through a major life moment, consider that your late period could be a symptom of that. Check in with your doctor to pin it down and if you're really having trouble, don't be shy about seeking the help of a mental health counselor.
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6. Travel

If you've been traveling, chances are you've been stressed. That alone can delay your period. But also, if you happened to be traveling across the International Date Line, it's possible that your period tracking got a little out of whack too — you might not actually be that late!
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