Hormonal pills, long-acting methods, and emergency pills are common drugs to prevent pregnancy, each with its own timing and side effects.
When people search for drugs to prevent pregnancy, they usually want clear, calm information they can act on right away. Maybe you want steady control over when to have a child, or you need to know what can help after sex when no protection was used. This article walks through the main medical options, how they work, and what real-world use looks like.
Every body is different, and the best method depends on your health, daily routine, and comfort with side effects. The goal here is to give you a clear map of the choices, so you can walk into a clinic, pharmacy, or doctor’s office already knowing which questions matter to you.
What Counts As Drugs To Prevent Pregnancy?
When people say drugs to prevent pregnancy, they usually mean medicines that change hormones or sperm movement so fertilization does not happen. These methods include daily pills, skin patches, vaginal rings, injections, implants under the skin, some intrauterine devices, and emergency contraceptive pills. All of these rely on active ingredients that change the way the reproductive system works for a period of time.
Alongside these medical options, there are barrier methods such as condoms and diaphragms, and permanent methods such as sterilization. Those do not fall under “drugs” in the strict sense, but they sit in the same family of tools people use to prevent pregnancy. Global health bodies such as the WHO contraception fact sheet and national agencies like the CDC birth control methods page group these options by how long they last and how they are used.
For a quick snapshot, the table below gathers the main medical methods often grouped as drugs to prevent pregnancy, with how you use them and how well they work with typical, everyday use.
| Method | How You Take It | Typical Effectiveness* |
|---|---|---|
| Combined birth control pill | One pill by mouth every day | About 93% (7 pregnancies per 100 users per year) |
| Progestin-only pill | One pill by mouth every day, same time | About 93% |
| Contraceptive patch | Patch on the skin, changed weekly | About 93% |
| Vaginal ring | Ring in the vagina for three weeks, then one week out | About 93% |
| Injection (shot) | Hormone shot every 8–13 weeks | Around 96% |
| Implant | Small rod under the skin of the arm | Over 99% |
| Hormonal IUD | Device placed in the uterus by a clinician | Over 99% |
| Copper IUD | Non-hormonal device placed in the uterus | Over 99% |
*Typical effectiveness means real-world use, including late pills or delays between visits.
Methods with lower effort from day to day, such as implants and IUDs, tend to sit at the top of the chart in terms of pregnancy prevention. Methods you have to remember often, such as pills and rings, work very well when used exactly as directed, but real life slips can lower the numbers.
Everyday Birth Control Pills
Daily pills are still the option many people think of first when they hear about drugs to prevent pregnancy. They are widely available, often covered by insurance or public programs, and come in many brands and dose patterns. Two main groups exist: combined oral contraceptive pills and progestin-only pills.
Combined Oral Contraceptive Pills
Combined pills contain two hormones, estrogen and a progestin. Together, they stop the ovaries from releasing an egg, thicken cervical mucus so sperm move less easily, and thin the lining of the uterus. Typical packs hold 21 to 24 active pills and a few placebo pills, though some packs skip the placebo days and let you have fewer withdrawal bleeds.
When taken at roughly the same time every day, combined pills are very effective. Perfect use brings the pregnancy rate down to under 1 per 100 users per year, while typical use sits closer to 7 per 100. Missed pills, long gaps between packs, or stomach bugs that cause vomiting can raise the chance of pregnancy.
Side effects can include nausea, breast tenderness, spotting between bleeds, and mood shifts, especially in the first few months. There is a small raised risk of blood clots for some users, so people with a history of clots, certain heart conditions, or migraine with aura are often steered toward other methods. Screening questions with a doctor or nurse help pick a safer option.
Progestin-Only Pills
Progestin-only pills, sometimes called the mini pill, contain no estrogen. They mainly work by thickening cervical mucus and, in some brands, by stopping ovulation. These pills are often a better fit for people who are breastfeeding, have higher clot risk, or cannot use estrogen for other medical reasons.
Timing matters more with many progestin-only pills. Some brands expect you to take the pill within the same three-hour window every day. A pill taken outside that window is treated as missed, and you may need backup contraception for a short time. Newer progestin-only pills can be slightly more flexible, but the idea is the same: steady daily use keeps protection strong.
Side effects can include irregular bleeding patterns, breast tenderness, or acne changes. Many users find that these settle down after a few months. If bleeding stays heavy or very frequent, a different dose or method can help.
Safer Drug Options To Prevent Pregnancy Long Term
Not everyone wants to think about birth control every day or every time they have sex. Long-acting methods place the work in the background for months or years. These are still drugs to prevent pregnancy, since they use hormones or copper inside the body, but they take less daily effort once in place.
Injection (The Shot)
The contraceptive injection is a progestin shot usually given in the arm or buttock. Depending on the brand and local practice, you return every 8 to 13 weeks for the next dose. The hormone stops ovulation and thickens cervical mucus, giving strong protection as long as you stay on schedule with visits.
Typical use shows around 4 pregnancies per 100 users per year, with better numbers when visits are on time. Common side effects include weight changes, irregular bleeding, and delay in the return of regular cycles after stopping. Bone density can drop slightly with long-term use, so some guidelines suggest checking in from time to time if you stay on the shot for several years in a row.
Implant Under The Skin
The implant is a small, flexible rod placed under the skin of the upper arm. It releases a low, steady dose of progestin and protects against pregnancy for three to five years, depending on the brand. Once placed, the implant sits in the top tier of effectiveness, with less than 1 pregnancy per 100 users per year.
The procedure uses local anesthetic and usually takes only a few minutes. Removal is also a short visit, and fertility returns quickly for most people. Irregular bleeding is the most common side effect, ranging from light spotting to long stretches without a period. Some users also report headaches or mood changes. A doctor or nurse can talk through which symptoms are normal and when a change in method might help.
Hormonal And Copper IUDs
Intrauterine devices sit inside the uterus and are placed by a trained professional during a clinic visit. Hormonal IUDs release progestin, which thickens cervical mucus and thins the uterine lining. Copper IUDs use copper ions to affect sperm movement and survival. Both forms offer over 99% protection and last from three to more than ten years, depending on the device.
Many people like IUDs because once they are in, there is nothing to remember before sex or every month. Hormonal IUDs often lead to lighter periods or even no bleeding after a while, while copper IUDs can bring heavier or more painful periods, especially in the first months. Cramping during insertion is common, so pain relief before the appointment can help.
Clinics usually screen for pregnancy, active pelvic infection, or unexplained bleeding before placing an IUD. If any of those show up, another method may be better until the issue is sorted out.
Emergency Drugs To Prevent Pregnancy After Sex
Even with a solid plan, condoms break, pills get missed, and sex sometimes happens without any method on board. Emergency contraception steps in after this kind of event. These drugs to prevent pregnancy do not end an existing pregnancy; they work before a pregnancy is established, mainly by delaying ovulation or stopping fertilization.
Two main types of emergency pills exist: levonorgestrel-based pills and ulipristal acetate pills. A copper IUD can also act as emergency contraception when placed soon after unprotected sex.
| Method | Time Window After Sex | Notes |
|---|---|---|
| Levonorgestrel emergency pill | Best within 72 hours, up to 120 hours in some guidance | Often sold over the counter; works less well late in the window or at higher body weight |
| Ulipristal acetate pill | Up to 120 hours | Prescription in many places; more effective late in the window and at higher body weight |
| Copper IUD | Up to 5 days | Placed by a clinician; most effective option and then works as long-term contraception |
Both types of emergency pill work best the sooner they are taken. They can cause short-term side effects such as nausea, a shift in the timing of the next period, or spotting. If the next period is more than a week late, a pregnancy test is a good idea.
Emergency pills are not meant as a regular, primary method. They are more expensive per use and a bit less effective than steady methods. That said, they are a helpful safety net when something goes wrong. Many health services now make them easier to get through pharmacies and clinics without long waits.
Side Effects, Risks, And Safety Checks
Every drug that prevents pregnancy can bring side effects. Many are mild and fade after a settling-in period. Others matter more and shape which method fits your health picture. Reading the leaflet and talking through your health history with a clinician helps match the method to your body.
Hormonal methods can bring headaches, sore breasts, changes in mood, changes in bleeding patterns, and, in some users, acne or changes in libido. Combined methods that contain estrogen carry a small raised risk of blood clots, stroke, or heart attack, especially in people who smoke, are over 35, or have certain medical conditions. This is why screening questions cover smoking, blood pressure, migraine type, and personal or family history of clotting problems.
Progestin-only methods avoid estrogen-related clot risks but still interact with other conditions and medicines. Some anti-seizure drugs and herbal products such as St John’s wort can lower hormone levels and reduce the effect of pills or implants. Telling your doctor or nurse about every regular medicine and supplement helps them spot clashes.
Non-hormonal methods such as the copper IUD sidestep hormone-related side effects but can bring heavier bleeding or stronger cramps, especially early on. Pain relief and patience can help during the first few cycles, and if bleeding stays very heavy, a review visit makes sense.
How To Choose Among Drugs To Prevent Pregnancy
When you stand in front of all these choices, it can feel like a lot. A simple way to sort through drugs to prevent pregnancy is to start with three questions: how often you want to think about birth control, how you feel about hormones, and how soon you might want a pregnancy later on.
Questions About Daily Life
Some people like the control of a daily pill and the chance to stop or switch quickly. Others know they tend to forget pills, travel across time zones, or have shift work that makes a strict schedule hard. If you love routine and phone reminders, pills can fit well. If you lose track of prescriptions or struggle with refills, an implant, injection, or IUD may take pressure off.
Feelings About Hormones
Hormonal methods are very effective and offer extra benefits for many users, such as lighter periods or less menstrual pain. At the same time, some people feel off on certain hormone doses or have medical reasons to avoid estrogen. Non-hormonal copper IUDs and condoms stay on the table for those who want to skip hormones altogether.
If you have a history of migraines with aura, high blood pressure, clotting problems, or certain cancers, combined hormonal methods may not be the first choice. In that case, progestin-only methods or non-hormonal options usually stand out more.
Plans For Pregnancy Later On
Most modern drugs to prevent pregnancy are fully reversible. Fertility returns after pills, implants, and IUDs at different speeds, but no method has been shown to harm the chance of pregnancy in the long run once it is stopped or removed. Still, the timing of your plans matters.
If you hope to try for a baby in the next year or so, a pill, ring, patch, or injection may feel flexible. If you want solid protection for several years with no daily effort, an implant or IUD usually makes more sense. Talking this through with a clinician helps you match the method to your plans rather than swapping methods every few months.
Talking With A Health Professional
Written information can take you only so far. The next step is a real conversation with a doctor, nurse, midwife, or sexual health clinician who can look at your full health picture. Bring a list of any medical conditions, medicines, and previous experiences with birth control, even if they were years ago.
Good questions to bring include:
- Which methods are safest for my age, weight, and health history?
- What side effects are common in the first three months?
- When should I come back if bleeding, pain, or mood changes feel too strong?
- How fast does fertility usually return after I stop this method?
- What costs, pharmacy visits, or follow-up appointments should I expect?
Remember that most drugs to prevent pregnancy do not protect against sexually transmitted infections. Condoms still matter for STI prevention, even if you are also on the pill, using an implant, or carrying an IUD. Regular STI testing based on your sexual activity stays part of full sexual health care.
This article gives general medical information about drugs to prevent pregnancy. It cannot replace personal advice from a clinician who knows your health history. If you have chest pain, severe headaches, shortness of breath, or sudden leg swelling while using hormonal methods, seek urgent care, as these can point to a blood clot or other serious problem.