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You’ve been taking your birth control pill, but the red wedding never came to pass. And while that sounds nice, it’s not great when you’re talking about your period.

The whole point of being on birth control is to control the timing of pregnancy.

Try not to worry, though! Missing your monthly isn’t an automatic cause for concern. There are several factors that can cause amenorrhea. (That’s a fancy term for missed periods.)

Even if you’re not a prima ballerina, exercise could be the culprit.

Moderate exercise is fine, but if you’ve recently started training for a long-distance race or made big changes to your daily fitness routine, your menstrual cycle could be affected.

Strenuous training disrupts hormones, and hormones control your flow.

If Friday rolls around and you’re sitting on the couch, looking like a fried Gudetama Egg, it’s time to assess stress sources ASAP.

Excessive stress is no yolk 😉. Your hypothalamus may be malfunctioning in its management of your hormones. It’s time for ETLSC (emergency tender loving self-care). First, breathe — and then review your workload.

In the U.S., 30 million people have an eating disorder such as anorexia or bulimia, and these disorders put women at a greater risk of missing their period.

Being 10 percent underweight or more can stop ovulation. Drastic weight loss and changes in your eating habits can interfere with your lady business.

Those aren’t the names of contestants on “America’s Next Top Model” but rather popular brands of continuous birth control pills.

These pills require taking active pills for 3 months in a row and then taking a week of inactive “placebo” pills. Aunt Flo might show up for some spotting between months but is only in full flow for 4 weeks out of the year when you’re taking the inactive pills.

This can also happen with injectable birth control methods like the Depo shot.

The most common condition that can cause periods to stop is polycystic ovary syndrome (PCOS).

Conditions like PCOS or hypothyroidism (having an underactive thyroid gland) can affect hormone production. The hormonal changes associated with both conditions can trigger changes in your uterine lining, leading to abnormal periods.

If you’re not pregnant and your periods stop, your doctor can check for any potential medical issues.

Just like weight loss can affect your moon time, so can weight gain.

Your body may produce unusually high levels of estrogen, which can make your periods irregular or make them stop altogether.

Real talk. If you’re sexually active (like 🍆-in-or-near-the-va-jay-jay active), it’s possible to become pregnant even if you’ve been taking your pills correctly. But that’s rare.

You may notice some spotting or you might skip your period completely. Your cycle is hormonally regulated while you’re on birth control, so you should see Bloody Mary every 28 days.

Missing two or more days of pills in a row increases the likelihood of becoming pregnant. Being late to get your injectable birth control by a day or two can also be risky.

Pregnancy symptoms can start as soon as a week after your missed period:

  • frequent urination
  • fatigue and low energy
  • lower backache
  • breast tenderness
  • nausea
  • vomiting

If you think a lot of these symptoms also describe period symptoms, you’re right! It’s best to stay calm, since these signs might just mean your period is coming ’round the bend.

Taking an at-home pregnancy test or visiting your gynecologist might help put your mind at ease. Grab one here.

Most birth control pills run a tight ship o’er the crimson tide. Hormones are regulated on a 4-week cycle, and you can expect your monthly friend to visit every 28 days.

On some birth control methods, you might get your period more frequently, less frequently, or not at all.

There are two types of birth control pills. One combines estrogen and progesterone, and the second is a progestin-only mini pill.

How does the pill stop pregnancy?

It takes a three-pronged battle approach:

  1. It tries to prevent ovulation from happening.
  2. It thickens cervical mucus to make it harder for sperm to reach your egg.
  3. If super-swimmers do still make it through, the pill thins your uterine lining and prevents the fertilized egg from implanting.

Most pill packs contain 28 pills each. The first 21 pills contain hormones and the last 7 are placebos.

TAKE 👏 THE 👏 PLACEBOS. This will get you in the habit of constantly taking the pills.

Taking your pill at the same time every day keeps your hormones stable. Three weeks of hormones, 1 week of placebos = 4 weeks of consistently taking the pill. Make sure to start your new pack on time too.

If you take your birth control pills SUPER consistently, they’re 99 percent effective at preventing pregnancy. Being human and sometimes taking the pill a few hours later than usual puts their effectiveness at a more realistic 91 percent.

Always check with your doctor if you start taking new meds, since some can interfere with the effectiveness of hormonal birth control.

If you haven’t missed any of your pills but your period still stood you up, pregnancy isn’t likely.

It may be the hormones in the pill. If you miss a second or third period, it’s worth it to take a pregnancy test or check with your doctor to make sure everything’s all right down there. Especially if you’re sexually active.

Once you know what’s blocking your lunar flow, there are options to get your cycle back on track:

  • Eat well and be healthy about weight management.
  • Exercise regularly and amp up training at a manageable pace for your body.
  • Relieve stress with yoga, walking, journaling, meditation, or breathing exercises.

You’re probably not pregnant. But trust your instincts.

If your cycle is usually regular but it’s been missing for a week and you’re wigging out, take a pregnancy test. If you don’t have a baby on board but your period still doesn’t show up next month, call your doctor.

If consistently taking a pill each day isn’t working for you, talk to your doctor about other birth control options. There are many.

And just a friendly reminder: The pill doesn’t protect against STIs. So if you’re single and mingling, make them rubber up (as Snape would say), “always.”