- Email: [email protected]
Reply to Dr. Briggs
Volume Number
127 6
knowledge, always contains 50 pg of mestranol. Therefore, if the study was a comparison of two products containing 50 pg of estrogen, then the highly sigthe Ovral and the nificant difference between Norinyl-I groups can only be due to the progestogen components. I’ have previously shown that norgestrel, but not norethindrone, antagonizes estrogen-induced changes in many plasma proteins. 1 would be grateful if this could be clarified. Michael Briggs Deakin Unwrsity Geelong 3220, .4 ustralia REFERENCE
1. Briggs, M. H.: Effects of oral progestogens on estrogeninduced changes in plasma proteins, J. Reprod. Med. 15: 100, 1975.
Reply to Dr. Briggs To the Editors: The two types of combined oral contraceptives that were used in the study on the pregnancy zone (PZ)
Correspondence
683
protein had the composition that was given in the paper. We are not very familiar with the various American synonyms for oral contraceptive, but we were told that the pill containing norethisterone, 1 mg., and mestranol, 0.1 mg., had the name of Norinyl 1 + 100. However, this pill was a brand in Sweden sold under the name of Conlunett. The study showed that the induction of PZ protein was significantly affected by the type and dosage of the drug. It seems likely that the “total estrogen effect” is of importance for the induction of PZ protein. and we agree completely with Dr. Briggs that the antiestrogenic effect of norgestrel in one of the combinations should be taken into consideration in this respect. Ma&G&-an Damber Bo zwn Srhoultz Torgny Stigbrand Departments of‘ Obstetrics and Gynecology and Physiological Chemistry University of t'muii S-901 87 UmeK, Sweden
127 6
knowledge, always contains 50 pg of mestranol. Therefore, if the study was a comparison of two products containing 50 pg of estrogen, then the highly sigthe Ovral and the nificant difference between Norinyl-I groups can only be due to the progestogen components. I’ have previously shown that norgestrel, but not norethindrone, antagonizes estrogen-induced changes in many plasma proteins. 1 would be grateful if this could be clarified. Michael Briggs Deakin Unwrsity Geelong 3220, .4 ustralia REFERENCE
1. Briggs, M. H.: Effects of oral progestogens on estrogeninduced changes in plasma proteins, J. Reprod. Med. 15: 100, 1975.
Reply to Dr. Briggs To the Editors: The two types of combined oral contraceptives that were used in the study on the pregnancy zone (PZ)
Correspondence
683
protein had the composition that was given in the paper. We are not very familiar with the various American synonyms for oral contraceptive, but we were told that the pill containing norethisterone, 1 mg., and mestranol, 0.1 mg., had the name of Norinyl 1 + 100. However, this pill was a brand in Sweden sold under the name of Conlunett. The study showed that the induction of PZ protein was significantly affected by the type and dosage of the drug. It seems likely that the “total estrogen effect” is of importance for the induction of PZ protein. and we agree completely with Dr. Briggs that the antiestrogenic effect of norgestrel in one of the combinations should be taken into consideration in this respect. Ma&G&-an Damber Bo zwn Srhoultz Torgny Stigbrand Departments of‘ Obstetrics and Gynecology and Physiological Chemistry University of t'muii S-901 87 UmeK, Sweden