Some women miss periods while on hormonal birth control, even when they are not pregnant. This is not abnormal or dangerous (although it is a little anxiety-producing!). However, if you go two or more months in a row without a period, or you miss your period after a month where you did not use all of your pills correctly, or you have symptoms associated with pregnancy, such as morning sickness or unusual breast tenderness, you should take a pregnancy test.
What Are Placebo Pills?
Birth control pills contain hormones that reduce your risk of pregnancy by stopping ovulation and thickening your cervical mucus to make it more difficult for sperm to get through. The hormones also thin the lining of the uterus, making it nearly impossible for a fertilized egg to implant. When taking birth control pills, it’s crucial to make sure you are taking them at the same time every day to maintain their effectiveness. Missing a pill could increase your risk of getting pregnant.
Placebo pills don’t contain hormones but are meant as placeholders to help you maintain your routine of taking a pill every day at the same time. If you stay in the habit of taking your pill, you are less likely to forget when you’re taking the active pills as birth control. Some placebo pills contain vitamins or minerals, such as folic acid or iron, to help lessen your period flow and premenstrual symptoms.
The placebo week is when you “should” normally get your period, though your period may not line up perfectly with the placebo pills. For instance, your period may start on the 3rd or 4th placebo pill day and may last through the first couple days of the new pill pack. You should start your new pill pack the day after taking your last placebo pill, even if your period is still going.
Why Is My Period Late?
When taking hormonal birth control pills, your body no longer ovulates, and the lining of your uterus becomes thinner. As a result, your periods often become lighter and less painful, especially when taking birth control on a long-term basis. In some cases, women don’t have much of the lining to shed. This can cause periods to stop coming.
Pregnancy is one reason you might skip a period or start later than usual. Excess stress is another reason, as it can impair the function of the hypothalamus, which is the part of your brain that manages the regulation of hormone production. Managing your stress more effectively and finding ways to lessen the stress in your life may help your period to come back and become more regular.
Changes to your eating habits can also impact your period, especially if you have lost weight quickly. If you’re underweight, your body may stop ovulating to protect itself. Women with eating disorders are particularly at risk for irregular menstrual cycles or a lack of periods. Excessive exercise may also cause your period to stop coming, especially strenuous training or long-distance events.
Could I Be Pregnant?
It’s rare to get pregnant while taking birth control pills. However, your body may show some early signs if you are pregnant and the pregnancy is causing you to not have a period. Some of these early pregnancy signs include:
- Breast tenderness or swelling.
- Mild cramping or vaginal bleeding.
- Nausea and/or vomiting.
- Mood swings.
- Food cravings or aversions.
- Constipation or other digestive changes.
- Lower back pain.
- Increased urination.
If you experience any of these signs, it’s important to take a pregnancy test before you begin your next pack of birth control pills.
Should I See a Doctor for a Missed Period?
In most cases, missing your period while taking birth control is not concerning. However, if you have missed one or more doses of your pills, you have experienced nausea with vomiting or diarrhea, or you have taken medication that could interfere with your birth control, you should take a pregnancy test to make sure you aren’t pregnant. You can also contact your healthcare provider with any concerns related to your missed period or symptoms you are experiencing.
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