Oral contraceptive

Male oral contraceptives remain a subject of research and development, and are not available widely (if at all) to the public. Studies continue of various alternatives, such as gossypol.

Female oral contraceptives, colloquially known as the Pill, are the most common form of pharmaceutical contraception, the prevention of unwanted pregnancy. They consist of a pill that women take daily and that contains doses of synthetic hormones (oestrogen and progesterone); the doses are adjusted in synchrony with the menstrual cycle. It is used by millions of women around the world, though the acceptance varies by region: approximately one-third of sexually active women in the United Kingdom use it, while in Japan what amounts to a boycott by doctors making huge profits from abortion has led to the pill being banned for nearly 40 years, and its recent introduction has seen very few women take it up.

The Pill works by preventing ovulation, as well as making the uterus less likely to accept implantation of an embryo if one is created, and thickens the mucus in the cervix making it more difficult for sperm to reach any egg. It is one of the most reliable forms of contraception, with less than one in 100 women using the pill becoming pregnant in a year of continuous use.

As mentioned above, the pills have to be taken daily and the amount of hormones contained in them varies over the course of the menstrual cycle. The pills are typically provided with special packaging to indicate the sequence in which they are to be taken. The failure rate of the pill is due to forgetting to take a pill, or to vomiting soon after taking one. If this happens, protection may be compromised and it is usually recommended to use an additional means of contraception. The effectiveness of the Pill can also be compromised by taking too low a dose to suppress your reproductive system, or by interactions with other medications such as antibiotics or anti-depressants such as St John's Wort. It also takes several months for the pill to take effect after you begin to take it, and many young women have found themselves unexpectedly pregnant during that window.

In those relatively few cases when the pill prevents the implantation of an embryo, this may be considered a form of chemically induced abortion by those who believe that human life begins at conception. Some therefore reject oral and other chemical contraceptives in favor of natural family planning (the only method of contraception allowed by the Catholic Church) or barrier methods such as condoms. The medical community generally does not consider this to be an abortion at this early stage, and many abortion opponents avoid labeling this as abortion by declaring that human life begins with the implantation in the wall of the uterus.

The Pill's development in the early 1960s and FDA approval of the drug on May 9, 1960 was one of the major factors leading to the sexual revolution that occurred later in the decade.