Hormonal Contraception

Revised 2018


Download PDF of this document:

English Version
Spanish Version
Chinese Version

Hormonal Contraception.pngHow do hormonal contraceptives work?

Hormonal contraceptives contain a progestin (progesterone medicine) with or without an estrogen. Both progestin and estrogen are made in a laboratory and are similar to the hormones that all women naturally produce. These two hormones together, or the progestin alone, work in several ways to prevent a pregnancy:

  • They can prevent ovulation (the release of an egg).
  • They make the mucus around the cervix (mouth of the womb) thicker so that sperm cannot enter the uterus (womb).
  • They make the lining of the uterus (womb) thinner to prevent a fertilized egg from attaching itself.


Why should I consider hormonal contraception?

When used correctly, all hormonal contraception choices are more than 99% effective in preventing pregnancy. They also have other potential benefits:

  • They reduce the risk of uterine, ovarian, and colon cancers.
  • They often reduce menstrual (period) blood flow.
  • They may reduce painful periods.


Are there women who should avoid using hormonal contraception?

Women with the following conditions should avoid using contraceptive agents that contain hormones:

  • Current or history of thrombophlebitis or thromboembolic (clotting) disorders
  • Current or history of stroke or coronary artery disease
  • Heart disease associated with the valves with thrombogenic (clotting) complications
  • Untreated and uncontrolled high blood pressure
  • Diabetes with circulatory problems
  • Headaches with neurologic symptoms
  • Major surgery with decreased activity
  • Known or suspected cancer of the breast or personal history of breast cancer


What different types of hormonal contraception are available?

  • Oral contraceptives: There are various formulations and doses that can be changed to meet your needs. Most contain a combination of estrogen and a progestin and are taken daily. They can be used cyclically (to produce regular menstrual cycles) or continuously (no regular menstrual cycles).
  • Injectable progestin: Contains a form of progestin that is given as a shot every 12 weeks. It may take up to 12 months for you to start ovulating again after you stop getting the shots.
  • Skin Patch: Contains a form of both estrogen and progestin that is given weekly for 3 weeks followed by a patch-free week. It may not be as effective in women who weigh over 90 kg (200 pounds). Estrogen levels in women taking the patch may be higher than in women taking pills. This may mean a higher risk of blood clots.
  • Vaginal Ring: A flexible, small ring containing both estrogen and progestin. It is used continuously for 3 weeks, followed by a week without the ring. It can be removed for a short time for sexual intercourse.
  • Progesterone intrauterine contraception: A small device that a doctor puts into the uterine cavity that contains progestin. It can be used for up to 5 years and can be removed earlier.
  • Implantable form: A single rod containing progestin that is implanted by your doctor under the skin. It is effective for up to 3 years and can be removed earlier.


What is emergency contraception (EC)?

EC is designed to prevent a pregnancy if it is taken within 72 hours after you have unprotected sex. If used properly, treatments are about 75% effective. EC prevents ovulation without affecting an already developing pregnancy. There are no medical reasons preventing women from taking EC. EC contains progestin, with or without estrogen, that is given in a single dose. In the United States, some brands can be purchased over the counter for women aged 17 and older.


What are the potential risks of using hormonal contraception?

  • Breast Cancer: A small number of studies show a slight increased risk of breast cancer in women under age 35 using hormonal contraception, but many more studies show no significant change in breast cancer risk. Overall by age 50 there is no increased risk of breast cancer in women using hormonal contraception.
  • Bone Strength: Injectable progestin may cause a shortterm decrease in bone mass. Data are limited for other forms of hormonal contraception.
  • Heart Attack: This is extremely rare. Although hormonal contraception slightly increases this risk, women over age 35 who smoke are at a higher risk.
  • Stroke: This is very rare. This risk may be increased in women who have migraines proceeded by visual changes (aura) or who are over age 35 and smoke.
  • Blood Clots (venous thromboembolism): Although the overall risk is very low, the risk is increased in all women who use formulations containing estrogen. This risk is higher in women who have underlying conditions that make them more likely to develop blood clots.

Please ask your doctor for more information about the benefits, risks, and side effects of these contraceptive agents.

Fact Sheets/Booklets

View more fact sheets and booklets written by the ASRM Patient Education Committee.
Patient Booklet teaser

Assisted Reproductive Technologies (booklet)

This booklet will help you understand in vitro fertilization (IVF) and other assisted reproductive technology (ART) that have become accepted medical treatments for infertility.
Patient Factsheet teaser

What do I need to know about Zika virus and trying to have a baby?

Common symptoms include fever, rash, joint pain, conjunctivitis (red eyes), muscle pain, and headache.
Patient Booklet teaser

Third-Party Reproduction

The phrase “third-party reproduction” refers to involving someone other than the individual or couple that plans to raise the child (intended parent[s]) in the process of reproduction.
Patient Booklet teaser

Infertility: an Overview (booklet)

Infertility is typically defined as the inability to achieve pregnancy after one year of unprotected intercourse.

Resources For You

The American Society for Reproductive Medicine (ASRM) is committed to providing patients with the highest quality information about reproductive care.

Contraception

Announcement Icon

Doctors Group Launches Ad Campaign for Ohio Issue 1

ASRM announced the launch of an ad campaign throughout Ohio urging voters to select “Yes on Issue 1” when they head to the polls on November 7.

View the Press Release
Videos Icon

Perimenopause

This video will cover perimenopause, also known as menopause transition, including the changes you can expect and the treatments for symptoms that are available. Watch Video
Patient Ed Icon

Intrauterine Device (IUD): A Long-acting Reversible Contraception

Birth control methods are different in how well they work. View the fact sheet
Patient Ed Icon

Noncontraceptive Benefits of Birth Control Pills

Most women will use birth control pills at some time in their lives. View the fact sheet
Patient Ed Icon

Nonhormonal Contraception

Despite a large number of contraceptive options available to couples, it is still thought that 50% of pregnancies in the United States are unintended. View the fact sheet
Infographic Icon

Contraception Infographics

ASRM has prepared infographics to illustrate the subject of Contraception better. View the Infographics

Find a Health Professional

Connect with reproductive medicine experts who will guide you through your unique journey. Our search tool allows personalized matches based on location, specialization, and expertise. Take control of your reproductive health with compassionate providers, innovative treatments, and unwavering support.
Search for an Expert
Healthcare professional eager to help a patient