Attempted Induction of Labor by Injections of Theelin

Abstract

Setting aside as irrelevant to this discussion the effects which the hormones of the anterior hypophysis are supposed to exert upon the hormones of the ovary, we may accept as reasonably well established at least 3 facts: that the endometrial changes which precede menstruation are controlled during the first half of the menstrual cycle by the follicular hormone of the ovary; that they are controlled during the second half of the cycle by the lutein hormone of the ovary; and that the actual menstrual flow is precipitated by the withdrawal of the lutein hormone, with which is associated the beginning retrogression of the lutein body. To emphasize the positive rather than the negative aspect of the theory, we may say that since biologic inactivity is unlikely at any time, menstrual bleeding is initiated by the ascendancy of the ovarian follicular hormone over the lutein factor. Arguing from this premise, it does not seem unreasonable to assume that the onset of labor in a normal pregnancy which has reached term may be the result of a similar sequence of events, the ascendancy of the same follicular hormone over the same lutein hormone, which is known to be present throughout pregnancy.

To test this theory and in the hope of precipitating the onset of labor, a series of experiments was undertaken on 8 pregnant negro women at full term by injecting (subcutaneously) varying amounts of theelin, the commercial preparation of the ovarian follicular hormone. At the same time, on the assumption that the follicular hormone can be secured by the aspiration of ovarian follicular cysts at laparotomy, fluid obtained from this source was injected into 2 other pregnant negro women who were also considered to be at term.