Lynestrenol as a contraceptive preparation. Experience with a micro-dosage formulation.

Lynestrenol 0,5 mg was administered daily for a total of 1 082 cycles to 143 women of proven fertility and natural sexual activity. Twenty-three women withdrew from the trial for various reasons, the commonest of which were menstrual distrubances. No unplanned or accidental pregnancies occured. The menstrual disturbances tended to become less troublesome with continuation of treatment, and this was noted in relation to other side-effects, of which headache and loss of libido were initially the most troublesome.