240 John Rock 



incidence of breakthrough bleeding, the % of untoward reactions, such as 

 transient nausea, which at 10 mg per day is experienced by about 10% of 

 patients, is definitely decreased. Moreover, ovulation is equally well inhibited 

 at lower dosages. 



In conclusion, it may be stated that in norethynodrel we have a substance 

 that suppresses ovulation and seems to be quite harmless. I believe that, with 

 availability of material and with the proper motivation, large numbers of 

 fairly illiterate people can be encouraged to use it. There is good reason 

 to conclude that Enovid will do no damage either to the woman herself or 

 to her future reproductive potential. 



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2. SOMMERS, S. C, The Pituitary and Hypothalamus. Chapter V in The Endocrinology 



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3. Rock, J., M. K. Bartlett and D. D. Matson, Am. J. Obst. & Gynec. 31, 3-12, 1939. 



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