How can you prevent a future unwanted pregnancy?

About 85% of sexually active women who do not use contraceptives become pregnant within a year. A woman can become pregnant while breastfeeding, from about 10 days after childbirth if not breastfeeding, and even during her menstruation. Withdrawal of the penis prior to ejaculation and periodic abstinence are not very effective methods of contraception and do not stop the spread of sexually transmitted disease or HIV. Here you can read about methods of contraception at Planned Parenthood   You can check which contraceptive method is the most appropriate for you if you have a health condition here

You can prevent an unwanted pregnancy with:

  • Total Abstinence. This is the only 100% effective way of avoiding pregnancy.
  • Use of contraceptives.

If you are sexually active and do not want to get pregnant, always use contraception. Some contraceptives are more effective than others; none are 100% effective. If contraception is not used during intercourse, ‘emergency contraceptives’ are available to avoid pregnancy. Below, we will give a summary of the methods of contraception, their effectiveness for typical women who use then, and some brief information on each. By typical women, we mean the average person, not the results from research studies which only report perfect use which is not real life. We will list them in 3 groups, from the most to the least effective. They are summarized in a link to a chart at the end of this piece. Side effects can be good or bad; the good side effects of many contraceptives are used to treat other medical conditions women suffer from like period problems, skin problems and PMS.


Methods of Contraception

Reversible methods.

They are under your control. You can change your mind and discontinue them when you wish. With the exception of those you can buy over the counter, a health care professional will assess you for method safety and explain the pros and cons of each method before providing it.

Highly effective methods result in less than one pregnancy per 100 typical women in a year of use: they are highly effective because once fitted, you don't have to remember to take them daily or every time you have sex and are not affected by vomiting or diarrhea. 

  • IMPLANT; Nexplanon is made up of a small flexible rod which is implanted under the skin of the upper arm, where it releases a very small amount of progestin hormone contraceptive. Its protection lasts for 3 years. Cycle change is to be expected in 80% of women but leads to early removal in only 1 woman in 5.
  • IUD is a small T-shaped device inserted into the uterus by a trained health-care professional. Protection lasts from 3-10 years depending on the device. They contain either copper or a very small amount of a progestin hormone.

Copper devices contain no hormones so cannot have hormone side effects. They can make periods heavier and crampy, usually just for the 1st few months. Sometimes the IUD can be expelled during a period so a woman will be taught vaginal self-examination to check it is still there after her period every month.

Hormone bearing devices initially make menses irregular but they then become lighter and may stop altogether. This is because the hormone stops the growth of the lining of the womb so there is no blood to lose. Many women find this change to their periods a great advantage. Although it is a hormone contraceptive, its effectiveness is not reduced by taking other medication or herbs.

Effective methods result in 6-12 pregnancies per 100 typical women in a year of use. They fail if they are forgotten, are late in being started or medication is taken which reduces their effectiveness.

  • INJECTABLE CONTRACEPTIVES are injected into a muscle on the arm or buttock (Depo provera) or just under the skin into fat (Sayana Press) every three months. Menstruation can become irregular and then usually stops in about 70% of women. This is because the hormone stops the growth of the lining of the womb so there is no blood to lose. It is the only contraceptive associated with weight gain which does not affect every woman using it. Although it is a hormone contraceptive, its effectiveness is not reduced by taking other medication or herbs.
  • ORAL CONTRACEPTIVES; “the Pill’ can contain just a progestin hormone (the single hormone or mini pill) which is taken every day or a combination of estrogen and progestin (combined pill) which are usually taken with a short break every month, the break specific to the type of pill. In most pills, the hormones prevent ovulation. The combined pill usually causes regular predictable bleeds whereas the mini pill is associated with irregular bleeds. The pills have to be taken exactly as directed and do not work after vomiting or severe diarrhea or if certain other medications or herbs are taken.
  • PATCHES AND RINGS are other ways of taking combination hormonal contraception. The patch is worn on the skin and changed weekly with a patch free week every month. The ring is worn in the vagina and changed every 3 weeks with a ring free week. Cycles and side effects are similar to the combined pill.

Less effective methods result in 18 or more failures per 100 typical women in a year of use. Condoms, diaphragms and caps are barriers to sperm. Condoms are the only contraceptive method considered effective in reducing the risk of sexually transmitted diseases (STD's) and HIV. Because a sexual partner can have an STI/ HIV but no symptoms, we would always recommend an effective method of contraception and a condom unless you are sure there is no risk. It is available over the counter.

  • MALE CONDOM. They are usually made from latex rubber (but you can get latex free) and can be used only once. Some have spermicide added to kill sperm. They act as a mechanical barrier, preventing direct vaginal contact with semen, infectious genital discharges, and genital lesions. It is important to put a condom on properly before intercourse starts because there can be sperm in pre-ejaculatory fluid.
  • FEMALE CONDOM. The FC2 female condom is a polyurethane sheath with 2 flexible rings to anchor the sheath after insertion and can be used only once. It acts as a mechanical barrier, preventing direct vaginal contact with semen, infectious genital discharges, and genital lesions.. It is available over the counter.
  • DIAPHRAGM is a dome shaped silicone rubber disc with a flexible rim worn in the vagina that covers the cervix and must be used together with spermicide. The one-size-fits-all Caya diaphragm (fits about 80% of women) requires a prescription. The diaphragm has to be inserted before sex and should be left in place for at least six hours after intercourse but not for longer than a total of 24 hours.
  • Femcap is dome shaped, made of silicone rubber and fits over the cervix. It should be used with spermicide. It is available on prescription and comes in 3 sizes.
  • SPERMICIDES come in gels, foams, creams, pessaries and films. They can be used alone or with barrier methods.
  • This is a single use vaginal spermicide. It fits over the cervix. It is available over the counter.
  • FERTILITY AWARENESS BASED METHODS depend on identifying the ‘fertile window’ in the cycle; that is, the days on which is it most likely to achieve pregnancy. They require tracking and interpreting the body’s fertility signs. Natural Cycles, an app, is now available to support this. The App has a much lower failure rate.
  • WITHDRAWAL, or coitus interruptus, is withdrawal of the penis which has to be before ejaculation or any release of pre-ejaculatory fluid as it also contains sperm.


Irreversible methods.

They are intended to be permanent. These methods result in less than one pregnancy per 100 typical women in a year of use:

  • FEMALE STERILIZATION; there are 2 methods. One is done surgically under anaesthesia by a procedure called laparoscopy (‘keyhole surgery’). The fallopian tubes are blocked by clipping or applying a ring, preventing the egg-cells from encountering the sperm cells and preventing any future pregnancies. The other is hysteroscopic sterilization which involves inserting a tiny device into each fallopian tube with a hysteroscope. The hysteroscope is an instrument that is inserted through the vagina and cervix and then into the uterus, performed in the clinic while awake. Complications are generally of the surgery.
  • MALE STERILIZATION, also known as vasectomy, is a quick operation performed under local anesthesia. The ability to get an erection and an ejaculation does not disappear. The sperm cells are just a very small part (1%) of the fluid and a man will not notice any difference in ejaculation. The body will absorb the sperm cells. Any complications are of the surgery.


Emergency methods.

There are hormonal and the copper IUD method. After the hormonal methods are used, barrier (condom) as well as a regular method of contraception must be continued for the rest of the cycle because the hormonal methods may just delay ovulation and pregnancy risk remains high. The IUD is highly effective and can be used for ongoing contraception immediately after fitting. More information can be found at the Emergency Contraception website 

  • Progestogen Pills such as Plan B One Step, Take Action, Next Choice One-Dose, My Way must be taken within 120 hours of unprotected sex. They are available without a prescription. They are about 87% effective, depending where you are in your cycle when they are taken
  • ella is an emergency contraception pill containing an antiprogestin hormone. It is effective for 5 days after unprotected intercourse, each day being equally effective. ella prevents about 94% of pregnancies.
  • Most combination (estrogens and progesterone) birth control pills can also be used. They must be taken within 72 hours of unprotected sex and are about 75% effective. Take the first dose as soon as possible and the second dose 12 hours For information on pill brands and number of pills per dose see
  • A copper IUD inserted within 5 days of unprotected intercourse acts as an emergency contraceptive. It is 99% effective, gives immediate ongoing contraception and can be kept in for the lifetime of the device, at least 10 years.


Chart of the Rates of Effectiveness of Different Contraceptives: