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This page provides basic knowledge about contraception. Is should only be used as guide and a source of information. It is not intended to be used as a diagnostic or treatment tool. The contents of this page will be more clear if you first familiarize yourself with the contents of the pages on menstruation and normal ovarian function.

Contraception is a very important subject in our modern society. The world is over populated. The cost of living is ever increasing. The cost of raising our children and giving them a decent education is getting more expansive. All these factors make it impractical for couples to have many children.

Modern science created reliable ways for couples to prevent pregnancies and plan their families . We will discuss the different methods, their limitations and possible complications. There is nothing like the best contraceptive. The best is the method most suitable for you and your partner.

The process of fertilization (becoming pregnant) in human beings is discussed at our web page Fertilization . All contraceptive devices and contraceptive drugs work in one OR MORE of the following ways:

  1. It acts as a barrier and prevents the sperms and the ovum to meet.
  2. It prevents ovulation (ovulation suppression).
  3. It prevents implantation.
The different methods will now be discussed in more detail. Oral contraceptives (better known as "The Pill") is the most used contraceptive and will be discussed first.
Different methods of Contraception
1. Ovulation Supression

The contraceptive pill works by suppressing or preventing ovulation. It contains a combination of synthetic estrogen and progesterone. The estrogen suppress FSH and LH secretion. (See The Pitiutary Gland for more detail).

The FSH and LH levels will decrease and there levels will be to low to stimulate the development of follicles in the ovary. If the follicles do not grow and enlarge, than ovulation can not occur and pregnancy is prevented.

Another way of putting it is that the body ( via the pituitary gland) is tricked into believing that the ovaries are secreting to much hormones and the FSH and LH levels drop very low.

This effect last only about thirty hours. That is way it is important to take the pill daily and at more or less the same time every day. The moment a pill is skipped or taken to late the FSH and LH levels can increase and a follicle might begin to develop.

The inject able contraceptive ( an injection given every two or three months) also suppresses ovulation. The injection does not contain estrogen . It only contains synthetic progesterone like hormones in high doses. The inject able contraception also changes the mucus at the entrance of the cervix. The mucus becomes sticky and thick and the sperms can not penetrate the thick mucus. It also effects the endometrium . The endometrium stays thin and proliferation ( thickening ) of the endometrium is absent. The thin endometrium will prevent implantation in case ovulation should occur. The contraceptive pill also effects proliferation ( thickening) of the endometrium but to a lesser extent.

A graphic illustration of the effects on the endometrium will follow later on this page. The side effects and complications will also be discussed later.

2. Prevention of Implantation

A foreign body in the uterine cavity will prevent implantation. This is the major mechanism through which the so called "loop" or intra uterine device prevents pregnancies. It is a small plastic device that is inserted into the uterus . It is left in the cavity for long periods ( up to five years). The modern devices are T - shaped and a copper wire is wind around the lower element of the T. The copper wire constantly releases copper ions . The ions effect the endometrium and make it unfavorable for implantation to occur.

A new type of intra uterine contraceptive device is now available. It continuously releases minute amounts of progesterone in the uterine cavity. It has thus a progesterone effect locally on the endometrium without or with very little systemic effect ( effects on other part of the body). The progesterone only contraceptive pill ( only known as the mini pill)suppresses the proliferation of the endometrium. It interferes with the preparation of the endometrium and prevents implantation. It also makes the mucus at the entrance of the womb thick and sticky. The thick mucus makes it difficult for the sperms to enter the womb.

3. Barrier Methods

The best known is the condom. It is a soft sheath made of special synthetic material. It fits over the erect penis and prevents sperms to enter the vagina. Another type is the diaphragm. It is a special devise that is inserted in the vagina in such a way that a synthetic membrane covers the cervix ( opening into the womb). Sperms are prevented from entering the womb.

A female condom is also available ( the edge of the condom sticks to the vulva{the organ around the vaginal opening} and sheath is inserted into the vagina.

The contraceptive (progesterone) injection and the progesterone only pills have an effect on the cervical mucus making it more difficult for sperms to enter the womb. They thus have an effect on ovulation, implantation and a barrier effect.

4. Contraceptive Pill

The contraceptive pill refers to the combination pill that contains both female hormones namely estrogen and progesterone. It contains synthetic altered biochemical substances with estrogenic and progestogenic effects , but these synthetic hormones are much more potent than the normal hormones formed in the body.

The next illustration shows the effect of the pill on the endometrium. (compare it with those in Normal Menstration).

The endometrium shows signs of progesterone stimulation but to a lesser degree than the normal premenstrual endometrium. The endometrium show signs of progesterone stimulation but is much thinner when compared to the endometrium in women not on oral contraceptives.

THE PILL usually consist of 21 active tablets ( containing estrogen and progesterone) and 7 placebo tablets (or "sugar tablets") containing no medical substances at all. While the placebo tablets are taken, there is is no endometrial stimulation and the inner layer of the endometrium is discarded. Menstruation begins. This amount of bleeding while you are on contraceptive tablets is usually less. This is due to the thinner endometrium. As soon as you start taking the active tablets again , the endometrium grows back and the bleeding stops. Compare it with the normal menstrual cycle HERE.

This drawing shows the discarded endometrium with bleeding.

The bleeding in somebody on "the pill" is usually less than it was before the pill.

We will now discuss possible side effects and complications due to oral contraception.

Irregular menstruations, spotting breakthrough bleedings.

When you are on "THE PILL" menstruation should occur every 28 days and it will normally start when are taking the placebo ("sugar tablets") Bleeding that occurs at any other time is refer to as breakthrough bleeding. It it a little it is referred to as spotting.

Skipping a tablet, having gastro enteritis ( vomiting and diaree)or certain medicines (certain antibiotics) can also cause breakthrough bleeding. Not enough hormones are absorbed to keep the endometrium intact. The endometrium is shed and a bleeding occurs at the wrong time.The antibiotics bind with the active ingredients of the pill forming substances that are not absorb into the body. Always check with your doctor before taking medicines while on the pill!

The pill hormones sometimes causes the lining to become so thin that the blood vessels are exposed and bleeding occur at the wrong time. These bleedings tend to be temporary and are very common during the first few months . It is if your body has to get use to "The pill". Depending on how heavy the bleeding and disturbing the bleeding is , it it possible to white a few months ( usually three) and in most cases the abnormal bleeding will disappear. The same type of breakthrough bleeding also occur when changing from one type of tablet to another type. If breakthrough bleedings persists ( longer than three months) or if it causing concern please consult a doctor. There are few ways to manage the bleeding , but in the hands of a properly trained person. Any breakthrough bleeding that start later( after the "pill" has been taken for a while without problems) should be medically investigated.

This drawing illustrates breakthrough bleedings.

The bleeding is usually scanty and called spotting.

Sometimes "the pill" causes the endometrium to become very thin, so thin that there is nothing to shed and the menstruations stop. If this occurs pregnancy should be excluded. The changes of a pregnancy are however very slight. There is usually another reason why the menstruation stopped. Usually due to the thin endometrium.

The pill is not fool proof and there is small change to conceive. The risk is about 1 in a thousand users per year. If a thousand women use "the pill" for one year, one of them might conceive. Some people might get mood swings, other might feel nausea while taking the pill. People with a history of liver diseases should consult a doctor before going on oral contraceptives. The same with persons who had blood clots previously.

Some people are concerned about a possible weight gain but many reseachers doubt if "the pill" has major effect on body weight.

There was also some concern about a slight increased risk for developing breast cancer in the past, but never proofed. "The pill " is in use for many years and no increased breast cancer risk was discovered until now.

Smokers should not take the pill after age 35 due to an increase risk of blood clots and strokes.

However, "the pill " is with us for many years , millions of women took and are still taking it. For the majority of them it was and is a save and reliable method of contraception. It is by far the most popular method of contraception.

The Progesterone Only Pill
In parts, also known as the mini pill (outdated name). It only contains one active hormone , progesterone. It has progesterone like effects on the womb and endometrium. It is less effective than the combination pill to suppress ovulation. It makes the cervical mucus at the entrance of the womb more sticky and less likely to allow sperms to pass. It has the same effect on the endometrium as the combination pill . The lining will be thin and more vascular. This can cause menstrual abnormalities in some women. The thin lining will interfere with implantation.

The same effect will occur on women on the injection.

The Progesterone Injection The inject able contraceptives contains only progesterone in an inject able form , There are different trademark available, an they are injected at two to three months intervals. The absorption occurs very slowly (from the injection site) and that is way the injections have a prolonged effect. The endometrium becomes thin and vascular. Menstruation is usually suppressed (especially if the 3 monthly preparation are used). This means that menstruations are completely stopped while on the injections. This will not cause any health risks. Menstruation is not a cleaning process , but only a sign that inner part of the endometrium ( the mucus membrane that lines the inside of the womb) is discarded. A fear of pregnancy is a concern in some women.

Due to its effect on the endometrium breakthrough bleedings and spottings can occur. (a very thin vascular endometrium)

The progesterone injections are also used in the treatment of endometriosis ( due to their effect on the endometrium).

The intra uterine devices,

They usually increase the amount of bleeding. Vaginal infections are more common and the risk of Salpingitis ( infections of the fallopian tubes) are also increased.

The manufactures of the progesterone releasing loop ( intra uterine device) claims but with research evidence that it less likely to cause complications than the copper containing device. The effectiveness of the different methods

We will use the so called HUNDRED WOMEN YEAR method to compare the different methods. This is a only a rough guide and some people with give slightly different figures.

If a hundred sexually active women are observed for one year:

  1. If they do not use any form of contraception ,about 90 of them will become pregnant
  2. If the use condoms there will be about 10 - 15 pregnancies.
  3. If they use the copper containing intra uterine devices there will be about 10 pregnancies during the first year it use , and about 6 pregnancies in later years. (the longer the loop is used , the more effective it becomes.
  4. If they use the progesterone only contraceptive about 6 pregnancies will occur. In lactating (breast feeding women) the pregnancy rate will be lower.
  5. If they use the combination pill, the contraceptive injection and the progesterone containing intra uterine device , less than one pregnancy will occur per 100 women per year.

    There are also other much less reliable methods not discussed on this page. The include the save period, the with drawl method and the use of spermacidal creams. None of them are very reliable and couples who are serious about contraception should not use them.

    Other methods include the SAVE PERIOD and Spermacidal creams.

Save Period
Intercourse is avoided during the fertile period. It is normalle calculated as follows:

Sperms can survive up to seven days and the ovum (egg cell) up to 3 days. Than from the length of cylce the expected date of ovulation is calculated. intercourse is than avoided during the seven days before ( some people add two more days ) and the three days after ( 2 days also added somtimes). We are sexual and emotional beiings and many couples will expierence diificulty in keeping to the save periods.


The sperm killing creams are very unreliable on their own and should only be used with male and female condoms and the diaphram.

The withdrawal method ( the male partner withdraws before ejaculation) is completely unreliable.