Female contraceptive pills, 2000.

'Femodene' and 'Microgynon' contraceptive pills manufactured by Schering AG. Before the 1950s, contraceptive pills were too expensive to mas produce because the hormones they contain had to be prepared in the laboratory from animal tisue. It only became economic for pharmaceutical companies to produce them when chemists discovered cheaper sources of the hormones in plants. These were used to make synthetic hormones, which could alter the female menstrual cycle, usually controlled by the body's natural sex hormones, preventing pregnancy. 'The Pill' was launched in 1960, and became closely linked with changing sexual attitudes in the 'swinging sixties'. There are now many different types of pill, each taken to a daily routine.