<P> The first widely used methods were five - day treatments with high - dose estrogens, using diethylstilbestrol (DES) in the US and ethinylestradiol in the Netherlands by Dr. Haspels . </P> <P> In the early 1970s, the Yuzpe regimen was developed by A. Albert Yuzpe in 1974; progestin - only postcoital contraception was investigated (1975); and the copper IUD was first studied for use as emergency contraception (1975). Danazol was tested in the early 1980s in the hopes that it would have fewer side effects than Yuzpe, but was found to be ineffective . </P> <P> The Yuzpe regimen became the standard course of treatment for postcoital contraception in many countries in the 1980s . The first prescription - only combined estrogen - progestin dedicated product, Schering PC4 (ethinylestradiol and norgestrel), was approved in the UK in January 1984 and first marketed in October 1984 . Schering introduced a second prescription - only combined product, Tetragynon (ethinylestradiol and levonorgestrel) in Germany in 1985. (1) By 1997, Schering AG dedicated prescription - only combined products had been approved in only 9 countries: the UK (Schering PC4), New Zealand (Schering PC4), South Africa (E-Gen - C), Germany (Tetragynon), Switzerland (Tetragynon), Denmark (Tetragynon), Norway (Tetragynon), Sweden (Tetragynon) and Finland (Neoprimavlar); and had been withdrawn from marketing in New Zealand in 1997 to prevent it being sold over-the - counter. (2) (3) (4) Regular combined oral contraceptive pills (which were less expensive and more widely available) were more commonly used for the Yuzpe regimen even in countries where dedicated products were available . </P> <P> Over time, interest in progestin - only treatments increased . The Special Program on Human Reproduction (HRP), an international organization whose members include the World Bank and World Health Organization, "played a pioneering role in emergency contraception" by "confirming the effectiveness of levonorgestrel ." After the WHO conducted a large trial comparing Yuzpe and levonorgestrel in 1998, combined estrogen - progestin products were gradually withdrawn from some markets (Preven in the United States discontinued May 2004, Schering PC4 in the UK discontinued October 2001, and Tetragynon in France) in favor of progestin - only EC, although prescription - only dedicated Yuzpe regimen products are still available in some countries . </P>

When was the morning after pill introduced in the uk