Inhibition of Ovulation in the Human 



111 



though rather low pregnanediol values were found in patients with the use 

 of the 3-methyl-ether of ethynylestradiol alone, it was not as regular and 

 dependable in its ovulation-inhibiting action as is norethynodrel. Moreover, 

 the clinical value of the 3-methyl-ether of ethynylestradiol was diminished, 

 inasmuch as the flow following its withdrawal was uncertain both in time 

 and in quality. 



In an effort to discover the mechanism whereby Enovid exerts its ovulatory- 

 inhibiting action, assays of urinary FSH were carried out on a few patients 

 in Worcester under Dr. Pincus' (25) direction before, during, and after 

 medication (Table 2). 



Table 2. Effects of Enovid on Urinary Follicle Stimulating Hormone 



(1) 20 mg/day for 4 days. 



(2) 20 mg/day — collection on 6th day. 



(3) 20 mg/day — collection on 10th day. 



(4) Six weeks after medication. 



(5) Premenopausal — collections at midcycle — received 20 mg/day. 



(6) Next midcycle. 



(7) 10 mg/day for 4 days. 



(8) Collected on the 4th day of medication. 



(9) Collected 10 days after last medication. 



One patient, aged 56 (No. 1), who, before treatment, had excreted 144 mouse units of FSH 

 per 24 hr, diminished her output to 60 mouse units following medication with 20 mg per 

 dayof Enovid for 4 days. In another woman, 54 years of age (No. 2), the FSH value decreased 

 from 24 to 7.2 mouse units per 24 hr after she had taken 20 mg per day for 6 days ; more- 

 over, the urine collected on the 10th day of treatment showed no detectable FSH. Six 

 weeks after cessation of medication, however, her FSH urinary content had risen to 79.2 

 mouse units per 24 hr. On the other hand, in a third menopausal patient, aged 60 (No. 4), 

 treated with only 10 mg a day for 4 days, urinary assay of FSH on the 4th day of medication 

 showed an elevation as compared to the pretreatment value. Moreover, in this case, the 

 postmedication value, 10 days after cessation of therapy, was less than during treatment. 

 The lower dose of Enovid administered to patient No. 4, or, possibly, a difference in threshold 

 response, may account for the different result. 



In a premenopausal woman, aged 42 (No. 3), who also received 20 mg per day of Enovid, 

 collections were made at midcycle. Whereas the midcycle premedication value was 32 

 mouse units per 24 hr, and the postmedication sample, collected at midcycle 10 days after 

 cessation of therapy, showed 48 mouse units per 24 hr, FSH was not detectable in the 24-hr 

 urine specimen collected at the midpoint of the medicated cycle. 



