Summary.
The new totally synthetic progestational steroid norgestrel has been subjected to a clinical trial in gynaecological and endocrine cases and for oral contraception, and its toxicity and side-effects have been investigated. The effect of norgestrel alone and in combination with ethinyl oestradiol in various dosage/time schedules on the endometrium has been studied. The previous reports of its effectiveness in low dosage combinations with oestrogen with absence of significant side-effects or toxicity have been confirmed. These findings, together with its very high potency, make it an important addition to progestational therapy in gynaecological practice and for oral contraception.