Birth Control

Here’s how hormonal birth control changes your body

Prescription birth control is an effective way to prevent pregnancy. But how exactly do those hormones change your body? Get answers from the experts!
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Key Points:

  1. Hormonal birth control changes your body in different ways to prevent pregnancy.
  2. Most birth control is reversible. When you stop using it, your fertility returns to normal, and you can possibly get pregnant if you have unprotected sex.
  3. Birth control can also be used for other health issues, like acne, painful, irregular or too-heavy periods and polycystic ovary syndrome (PCOS).

Hormonal birth control is very safe for most people. But if you’re already taking a prescription birth control treatment—or weighing the pros and cons of birth control you haven’t tried yet—you may wonder how exactly the hormones change your body.

If you already have a handle on the types of birth control available, read on for a detailed breakdown of how hormonal birth control changes your body. Ready to get birth control online? Start a convenient + discreet $15 online consultation with Dr. B today!

How do hormones affect fertility?

In a typical cycle, ovulation occurs when hormones signal the ovaries to release a mature egg. The egg then travels down the fallopian tubes to the uterus. If an egg meets a sperm in the fallopian tube, it may become fertilized.

If a fertilized egg reaches the uterus, it can implant into the thick, cushy lining that’s been developing for the past few weeks. When a fertilized egg implants into this lining, it can develop into a fetus (the baby growing inside the womb).

If no egg reaches the uterus or if the egg does not implant, the lining of the uterus begins to fall off and comes out through the cervix and vagina. This is your monthly period.

How birth control changes your body

Hormonal birth control prevents pregnancy by changing how your menstrual cycle works in three ways:

  • First, it prevents ovulation by stopping the uterus from releasing an egg. Without an egg, you can’t get pregnant.
  • Second, it tells the uterus lining to stay thin, making it harder for an egg to implant.
  • Last, it turns cervical mucus sticky and thick. This acts like a sticky glue that traps sperm before they can swim into the uterus and fallopian tubes.

When taken correctly, most methods are over 99% effective at preventing pregnancy. But each form of birth control comes with its own complications. Maybe you don’t want to take pills at the same time every day. Maybe you want a barrier method that protects against sexually transmitted illnesses, too.

It’s best to know how each type works before choosing which is best for you.

What else does birth control do?

On top of preventing pregnancy, the hormones in birth control pills can offer other benefits.

Birth control that contains both progestin and estrogen (like combination pills) can also lower the risk of ovarian and uterine cancers and improve endometriosis symptoms. And some are prescribed to regulate hormone levels and treat severe acne, severe premenstrual syndrome, painful or irregular periods, or polycystic ovary syndrome (PCOS).

Can birth control cause infertility?

Birth control does not impact long-term fertility unless you choose a permanent sterilization method (like a vasectomy for people with penises or tubal ligation for people with uteruses).

The pill, patch, ring, shot, IUD and implant are reversible. That means that if you stop using them, you could become pregnant if you have unprotected sex.

Can you get missed periods on birth control?

Many people who use the implant or IUD often do not get periods anymore or experience lighter periods. The pill, patch and ring can be used back-to-back to intentionally prevent monthly bleeding.

To find out if it’s safe for you to use your birth control this way, talk to a healthcare provider.

Drawbacks of birth control

There are potential downsides to certain kinds of birth control.

The shot (Depo-Provera) is associated with weight gain. It can also take a few months to leave your system, so it can take 9-10 months before you can try to get pregnant after stopping the shot.

Some methods of birth control aren’t appropriate for everyone. People who are over 35 and have a history of smoking shouldn’t take combination birth control. People who breastfeed should talk to their doctor before taking birth control with estrogen. It’s also important to talk to your doctor if you have a history of certain kinds of cancer or blood clots, as these can be made worse by certain hormonal methods.

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How Dr. B can help you get birth control online

Not sure which method is best for you? Dr. B can help you choose from the comfort of your couch!

Fill out a $15 online consultation to get started—no video call required. A licensed healthcare provider will review your treatment. If necessary, they’ll reach out to learn more about your needs and answer any questions you have. If appropriate, they’ll send a birth control prescription to your pharmacy of choice.

Dr. B offers over 150 birth control medicines—including the pill and the ring. Learn more about how to get birth control online with Dr. B. Or get started today on a discreet, convenient online consultation.


Barr, N. G. (2010). Managing adverse effects of hormonal contraceptives. American Family Physician.

Britton, L. E., et al. (2020). CE: an evidence-based update on contraception. The American Journal of Nursing.

Cooper, D. B., et al. (2022). Oral contraceptive pills. StatPearls Publishing.

Mayo Foundation for Medical Education and Research. (2022). Progestin (oral route, parenteral route, vaginal route) description and brand names.

Sathe, A., et al. (2022). Medroxyprogesterone. StatPearls Publishing.

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