Abstract
Plasma oestradiol 17β and progesterone levels in 11 patients admitted to hospital for threatened premature labour of unknown aetiology were compared with those of women at similar stages of gestation whose pregnancy was normal. Oestradiol levels in the study group were slightly higher than in the normal controls but their progesterone levels were significantly lower. This progesterone deficiency increased the oestradiol/progesterone ratio in the study group patients, and it increased still more as the progesterone withdrawal continued during premature labour.
Since uterine activity during pregnancy is regulated by a balanced action of several factors a deficiency in progesterone, an opponent of uterine activity, creates a regulatory imbalance which, if uncorrected, provokes premature labour. An increase in uterine volume stimulates uterine activity, and the present study reinforced our previous conclusion that the uterine-volume/plasma-progesterone ratio is a more accurate measure of the state of regulatory balance than the progesterone level alone.
The cause of the progesterone deficiency in these cases remains unexplained, but we suggest that placental growth and function are contributory factors. We are investigating ways of correcting the resulting imbalance in the regulatory mechanism.
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- CSAPO A. I., JAFFIN H., KERENYI T., DEMATTOS C. E., DE SOUSA FILHO M. B. FETAL DEATH IN UTERO. Am J Obstet Gynecol. 1963 Dec 1;87:892–905. doi: 10.1016/0002-9378(63)90287-4. [DOI] [PubMed] [Google Scholar]
- Caldwell B. V., Tillson S. A., Brock W. A., Speroff L. The effects of exogenous progesterone and estradiol on prostaglandin F levels in ovariectomized ewes. Prostaglandins. 1972 Mar;1(3):217–228. doi: 10.1016/0090-6980(72)90006-8. [DOI] [PubMed] [Google Scholar]
- Csapo A. I., Kivikoski A., Wiest W. G. Massive initial prostaglandin impact in postconceptional therapy. Prostaglandins. 1972 Aug;2(2):125–134. doi: 10.1016/0090-6980(72)90046-9. [DOI] [PubMed] [Google Scholar]
- Csapo A. I., Knobil E., van der Molen H. J., Wiest W. G. Peripheral plasma progesterone levels during human pregnancy and labor. Am J Obstet Gynecol. 1971 Jul 1;110(5):630–632. doi: 10.1016/0002-9378(71)90242-0. [DOI] [PubMed] [Google Scholar]
- Csapo A. I. On the mechanism of the abortifacient action of prostaglandin F 2 . J Reprod Med. 1972 Dec;9(6):400–412. [PubMed] [Google Scholar]
- Csapo A. I., Pulkkinen M. O., Ruttner B., Sauvage J. P., Wiest W. G. The significance of the human corpus luteum in pregnancy maintenance. I. Preliminary studies. Am J Obstet Gynecol. 1972 Apr 15;112(8):1061–1067. doi: 10.1016/0002-9378(72)90181-0. [DOI] [PubMed] [Google Scholar]
- Csapo A. I., Pulkkinen M. O., Wiest W. G. Effects of luteectomy and progesterone replacement therapy in early pregnant patients. Am J Obstet Gynecol. 1973 Mar 15;115(6):759–765. doi: 10.1016/0002-9378(73)90517-6. [DOI] [PubMed] [Google Scholar]
- Csapo A. I., Sauvage J. P., Wiest W. G. The relationship between progesterone, uterine volume, intrauterine pressure, and clinical progress in hypertonic saline--induced abortions. Am J Obstet Gynecol. 1970 Nov 15;108(6):950–955. doi: 10.1016/0002-9378(70)90340-6. [DOI] [PubMed] [Google Scholar]
- Poyser N. L., Horton E. W., Thompson C. J., Los M. Identification of prostaglandin F2-alpha released by distension of guinea-pig uterus in vitro. Nature. 1971 Apr 23;230(5295):526–528. doi: 10.1038/230526a0. [DOI] [PubMed] [Google Scholar]
- Pulkkinen M. O., Liukko P., Piiroinen O., Rauramo L. Induction of midtrimester abortion by increasing intra-uterine volume. Acta Obstet Gynecol Scand. 1973;52(1):9–12. doi: 10.3109/00016347309158482. [DOI] [PubMed] [Google Scholar]
- Rado A., Crystle C. D., Townsley J. D. Concentration of estrogens in maternal peripheral plasma in late pregnancy, during labor and post partum. J Clin Endocrinol Metab. 1970 Apr;30(4):497–503. doi: 10.1210/jcem-30-4-497. [DOI] [PubMed] [Google Scholar]