Combined oral contraceptive pill

The **combined oral contraceptive pill** (**COCP**) is a contraceptive for women. It is often called the **birth control pill** or simply **"the pill."** Birth control pills contain hormones that affect the hormones of the woman that takes them and makes pregnancy not possible  for around 24 hours. The pill puts a pause on the ovarian cycle so that an egg (called an ovum) is not released. It also makes the lining of the uterus thicker. 

Birth control makes the women who take them unable to get pregnant. Women who take the pill will not become pregnant during sexual intercourse. When a woman stops taking the pills, she will become fertile again. When taken as prescribed, the pills are one of the safest methods of contraception as is over 99% effective.

Another type of contraception to prevent pregnancy is the condom for men. There is a female condom for women who do not want to or can not take birth control.

In the 1950s, scientists (such as Carl Djerassi, George Rosenkranz and Alejandro Zaffaroni) realized that the hormone progesterone stopped women from making eggs (stopped ovulation).  After this discovery, the combined oral contraceptive pill was created. The combined oral contraceptive pill has two female hormones: estrogen and progesterone. Some oral contraceptive pills have only progesterone. These are often called the "minipill".

The combined oral contraceptive pill is thought to be safe and usually works well.

## In the United States 
In the United States the combined oral contraceptive pill was first given to women in 1960. It was a revolutionary breakthrough in contraception for two reasons. First, it is very effective at preventing pregnancy if it is used in the right way. Second, it was the first contraceptive to completely separate the act of contraception (in this case the taking of a pill) from sexual intercourse itself. Unlike barrier methods, when a woman is "on the Pill," she and the man are usually not even aware of it during sexual intercourse, which seems and feels very natural. The woman may be on the pill without her partner knowing. The couple can have sex at any time they wish; they don’t need to interrupt foreplay to put birth control in place, and they can feel the physical sensations and emotional closeness of intercourse without interference from a male or female condom. Unlike coitus interruptus, when a woman is on the Pill, intercourse usually ends with her man reaching orgasm while inside the vagina, which both the man and woman usually find very pleasurable. It may also  make women's menses shorter and with less bleeding, as well as helping her complexion, which most women like. For all of these reasons, the Pill is very popular. In 2005, more than  80 million women across the world used the Pill. It is the most common method of contraception in the United States, with four out of five women there having used the pill for birth control at some point in their lives. Use of the Pill is different in different countries, Both single women and married women use the Pill in large numbers.

## Different countries use different contraceptives
The choices a woman has for contraception - and whether contraception is even available - depends on what country she lives in. These things are different in different countries. In the United Kingdom, one out of every 4 women aged 16–49 were using the Pill as at 2006 (either the combined pill or progestogen only pill ("minipill")). compared to only 1% of women in Japan. Local culture and habits affect whether or not people use the Pill.

In some countries, women do not really have a choice because only one kind of contraception is available. In some countries (like Algeria, Morocco, and Zimbabwe), the Pill is the most common method offered by national family planning programs.  In other countries, like India, national family planning programs only offer female sterilization (a surgery which makes a woman unable to ever have children again). Other countries, like Egypt and Vietnam, only offer the IUD, intrauterine device. Most often, the Pearl Index is used to calculate effectiveness rates. However, some studies use decrement tables.

The typical use pregnancy rate for women taking COCPs measures how many women get pregnant while taking them. All women are not equally likely to get pregnant while taking COCPs. Different groups of women have different typical pregnancy rates. Overall, between 2% and 8% of women taking COCPs get pregnant every year. If they are used perfectly only 0.3% become pregnant each year.

COCPs can prevent pregnancy if the first pill is taken no later than 5 days after a woman starts menstruating. If the treatment is started at any other time in the menstrual cycle, COCPs cannot safely prevent pregnancy for the first 7 days of use. During this time, a woman needs to use other types of contraception in order to prevent pregnancy. When active pills have been taken for 7 days, they can work well to prevent pregnancy. They should be taken at about the same time every day.

Certain things can make COCPs not work as well:
#If a woman misses more than one active pill in a packet. (Certain packets also contain "placebo pills", which do not have any hormones in them. COCPs are usually used for three weeks out of the month. The woman then takes a break from the pills for a week. Some packets have placebo pills for women to take during this week, so that the woman does not get out of the habit of taking a pill every day. If a woman does not take placebo pills during this week, it does not make her more likely to get pregnant.)
#If a woman waits more than a week to start taking COCPs (active pills) again, after her week-long break.
#If a woman's body has problems with absorbing active pills (for example, if the woman has diarrhea or vomiting).
#If a woman is taking other medicines which interact with her COCPs to make them not work as well (for example, medicines which lower her estrogen or progestogen levels).

The traditional medicinal herb St. John's Wort also seems to make COCPs not work as well. This is because of the way St. John's Wort affects the liver.

## Non-contraceptive uses 
The Pill can be used for other things besides contraception. There are many medical conditions that are caused by problems with hormone levels. Because the Pill has hormones in it, it can treat these conditions. Some of these conditions are:
*Anemia caused by menstruation
*Painful menstruation (dysmenorrhea)
*Mild or moderate acne.
If a woman's menstrual cycle is not regular, the Pill can make the woman menstruate on a regular schedule. The Pill can also be used to treat certain problems that cause bleeding from the uterus.

Women who use combined oral contraceptives are less likely to get cancer of the ovaries. If a woman takes Pill for five years, her risk for getting ovarian cancer is cut in half. Women taking the Pill are also only half as likely to get endometrial cancer than women who have never taken the Pill. The longer a woman uses the Pill, the more her risk of getting endometrial cancer drops. However, women who take the Pill have a higher risk of getting breast cancer and cervical cancer.

## References