Two new types of antiprogestins that can suppress menstruation
and could end the monthly misery many women suffer have passed
their first tests in animals, scientists report in Europe's
leading reproductive medicine journal, Human Reproduction.*
Studies in rhesus macaque monkeys show that that one drug - ZK
137 316 - can, depending on dose, allow ovulation but block
menstruation, while the other - ZK 230 211 - blocks both
ovulation and menstruation. Of great importance, both the drugs
block the effects of oestrogen on the lining of the uterus, thus
preventing the potentially dangerous build-up of endometrial
cells caused by the action of unopposed oestrogen. The studies
have been carried out in Dr Robert Brenner's laboratory in the
Division of Reproductive Sciences at Oregon Regional Primate
Research Centre in the USA. Rhesus macaque monkeys were used
because they are one of the only animals that regularly
menstruates and the mechanism in the brain, ovary and uterus
controlling their periods is identical to t