GREGORY PINCUS 
It is obvious that faithful tablet-taking gives practically com- 
plete contraception. But even when some tablets are missed, 
a clear reduction in fertility occurs, for among these women 
when no contraceptive is being used the conception rate is 
210 for 100 ““woman years” of exposure. Dr. Venning has 
compared the conception rates reported for Enovid and for 
various other methods of contraception. This comparison 
is shown in Table III; it is obvious that Enovid taken by 
mouth offers by far the most efficient method of conception 
control. 
In conducting these trials with Enovid, we have maintained 
a close follow-up of all of the volunteer subjects. In addition to 
regular monthly visits with a nurse or social worker, we have 
conducted annual examinations of most of the women>4, I 
should like here to present data on certain aspects of the use of 
the ovulation-inhibiting, menstruation-regulating regimen. I 
have already indicated that a succession of quite regular men- 
strual cycles is usual in women taking Enovid. In addition, we 
have questioned patients from time to time concerning the nature 
of the menstrual flow. Their replies indicate that, compared with 
the premedication flow, menstruation appears to be ordinarily 
unchanged or somewhat lighter, but seldom heavier. This ability 
of the drug to reduce menstrual flow has led to its therapeutic 
use in many conditions involving excessive menstrual flow. 
In order to study the effect of Enovid on lactation, we have 
been giving the drug to a group of women three to six weeks 
after the birth of a baby. At the highest dose (20 mg. a day) 
a substantial majority noted a reduction in milk production, 
but at the lowest dose (2-5 mg. a day—which is just as effective 
in contraception) the majority noted no change, and those 
finding lactation less just about equalled those finding it in- 
creased. 
Our patients have kept track of body weight changes. There 
is a suggestion that a significant proportion of women taking the 
10 mg. dose tend to gain weight, but this is not evident in the 
lower dosage groups, and over-all reports of weight gain tend 
to balance those of weight loss. 
84 
