A Basis for Comparing the Potency of Gonadotropins

Abstract

Summary

1. Three types of gonadotrophins were compared on the basis of the capacity of each to induce ovulation 18 hours after a single subcutaneous injection of a minimal ovulating unit of the extract into mature diestrous mice weighing at least 20 g. The minimal ovulating dose is defined as the smallest amount of gonadotrophin which will induce ovulation in 70% of a group of 10 or more mice similarly treated. 2. The minimal ovulating dose for the chorionic gonadotrophin was found to be 1.0 I.U.; for the pregnant mare's serum, approximately 5.0 I.U.; for the extract of the anterior pituitary of the horse, 0.25 Fevold-Hisaw Unit. 3. This bioassay method is of definite value in comparing the potency of various gonadotrophins.