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PubMed1992

Medical termination of early pregnancy with mifepristone (RU 486) followed by a prostaglandin analogue. Study in 16,369 women.

We report the results of a large-scale trial with mifepristone (RU 486) followed by the administration of a prostaglandin (PG) analogue for the medical termination of early pregnancy. Altogether, 16,173 patients from 300 centers were evaluated. 48 women (0.3%) were lost to follow-up prior to, and 416 (2.6%) after the PG administration, and therefore the efficacy was evaluated in 15,709 women. Overall, the success rate was 95.3%, with no statistical difference regarding the nature and dose of PG used. The median duration of bleeding was 8 days, being 12 days or less in 89.7% of the women. Bleeding was significant enough to necessitate a vacuum aspiration or a dilatation and curettage in 0.8% of the cases. A blood transfusion was necessary in 0.1% of the women (11 patients). Serious cardio-vascular side-effects were reported in 4 cases after the PG (sulprostone) injection: they consisted of one acute myocardial infarction attributed to a coronary spasm, and in marked hypotension in the other 3 women. All patients recovered uneventfully. In conclusion, RU 486 followed by a PG analogue provides an efficient and safe medical alternative to surgery for early pregnancy termination, provided that the recommended protocol is adequately followed and the contraindications to prostaglandins are respected.

Abortifacient Agents, Nonsteroidal↗
PubMed1992

Direct effects of progesterone and antiprogesterone on human sperm hyperactivated motility and acrosome reaction.

OBJECTIVE: To study the direct effects of progesterone (P) and its antagonist RU486 (mifepristone) on sperm hyperactivation (HA) and acrosome reaction. DESIGN: Prospective evaluation of semen samples incubated in capacitation media with P and/or RU486. SETTING: University-affiliated tertiary care center. PATIENTS: Normal healthy volunteers. INTERVENTIONS: Semen samples were incubated in media with P or RU486 alone or in combination, and aliquots were taken at 10 minutes, 1, 5, and 24 hours for HA analyses by computer-aided sperm analysis system, and at 0, 5, and 24 hours for assessment of acrosome reaction by fluorescein-labeled Pisum sativum (pea) agglutinin. MAIN OUTCOME MEASURES: HA and acrosome reaction. RESULTS: Sperm HA was significantly increased at 10 minutes by P both at 10(-7) M (9.27 +/- 1.59%; mean +/- SEM) and 10(-6) M (9.39 +/- 1.94%) when compared with untreated spermatozoa (5.62 +/- 1.59%). The stimulatory effect of P on sperm HA was transient because this was not observed after 1, 5, and 24 hours of incubation. The antiprogesterone RU486 (10(-6) M) alone had no effect and did not abolish the stimulatory effect of P on HA. The %HA was further enhanced by the addition of RU486 at 10(-6) M to P at 10(-7) M (12.43 +/- 3.31%) or P at 10(-6) M (13.52 +/- 4.10%); however, this effect was not significantly different from P alone. Coincubation of P or RU486 with spermatozoa during capacitation did not stimulate the acrosome reaction in the concentrations tested. CONCLUSION: Progesterone directly stimulates human sperm HA transiently. Progesterone has no significant effect on acrosome reaction in capacitating spermatozoa. The effects of P are rapid and not counteracted by RU486, suggesting that the mechanism of action of P may not be mediated by specific P nuclear receptors.

Acrosome↗
PubMed1992

Abortion: epidemiology, safety, and technique.

In 1991, the abortion literature was characterized by articles relating to 1) epidemiologic issues in abortion care, 2) advances in knowledge and experience with medical abortifacients such as mifepristone (RU 486), and 3) cervical ripening prior to abortion with the use of both mifepristone and prostaglandins. Technical methods of achieving termination of pregnancy continue to be similar in the United States, the United Kingdom, and Europe, although induction-abortion times are generally slower in Europe than in the United States. Surgically, dilatation and evacuation procedures continue to be more common in the United States than in other countries. The effectiveness of mifepristone is undisputed, and the recommended dose for early first-trimester termination is being compared with lower dose alternative regimens. There is additional evidence that at least in the short term, the negative psychological sequelae of abortion are infrequent and are inconsequential as a public health issue.

Abortion, Incomplete↗
PubMed1991

Abortion.

In 1990 abortion literature was characterized by articles relating to 1) the safety of surgical abortion procedures, 2) advances in knowledge and experience with medical abortifacients such as mifepristone (RU 486), and 3) reviews of psychologic and ethical considerations. Although technical methods differ greatly between countries and continents, there is increasing similarity between termination protocols in the United States, the United Kingdom, and Europe. The advent of mifepristone will make this even more so. Surgically, although dilatation and evacuation procedures are far more common in the United States than in other countries, the literature reflects a fine-tuning of analysis and technique, with safety the major consideration. Knowledge about the effectiveness of mifepristone continues to grow, and the effective dose for early first-trimester termination appears established. There is increasing evidence that at least in the short term, the negative psychologic sequelae of abortion are infrequent and are inconsequential as a public health issue.

Abortion, Induced↗
PubMedDate not supplied

Contraceptive development and testing in the United States of America.

Contraceptive development, including the development of IUDs, is discussed in light of the changing regulatory role of the FDA. The paper considers how the FDA and the government affect contraceptive development. Events that led to the demise of IUD use in the United States probably will have long-lasting effects on all future contraceptive development by the pharmaceutical industry in the United States.

Contraceptive Agents↗
PubMed1991

The anti-progestin RU486 stabilizes the progestin-induced fatty acid synthetase mRNA but does not stimulate its transcription.

Progestins induce fatty acid synthetase (FAS) in breast cancer cell lines, both increasing its gene transcription and mRNA stabilization (Joyeux, C., Rochefort, H., and Chalbos, D. (1989) Mol. Endocrinol. 4, 681-686). In vitro run-on transcription assays show that RU486, in contrast to progestin, inhibits FAS transcription by 40-50%. Moreover and surprisingly, anti-progestin RU486 also stabilizes FAS mRNA 3- to 4-fold in MCF7 cells as measured by chase experiments in the presence of actinomycin D or cordycepin or after short cell labeling with [3H]uridine. Dexamethasone is inefficient in increasing the half-life of FAS mRNA in MCF7 cells. RU486 had no effect on MDA-MB 231 cells which contain glucocorticoid but no progesterone receptors, indicating that the progesterone receptor is implicated in this regulation. RU486-induced mRNA stabilization allows delayed accumulation of FAS mRNA. These results indicate that the progesterone receptor can be activated separately to stimulate gene transcription or stabilize mRNA.

Cell Line↗
PubMed1990

Interference with ovulation by sequential treatment with the antiprogesterone RU486 and synthetic progestin.

Seven healthy women were treated with the antiprogesterone RU486, 25 mg/d, on days 1 to 14 of the follicular phase of the menstrual cycle, followed by the synthetic progestin NET in the luteal phase of the cycle. Venous blood samples were collected twice per week. Serum E2, P, and RU486 concentrations were determined by RIAs, and FSH and LH by immunofluorometric assays. Ultrasonography was used to measure the sizes of the follicles. Serum concentrations of FSH and LH were not suppressed during the treatment. Ovulation was apparently suppressed during RU486 treatment according to E2 and P concentrations and ultrasonography findings. During NET treatment, some evidence of ovulation and follicle growth were found during the first treatment periods. During the third treatment cycle, there was no evidence of ovulation (n = 2). Estradiol concentrations were sufficient to stimulate normal proliferative growth of the endometrium during the treatment. Control of bleeding was good. The exact mechanism of action of RU486 on steroid synthesis and ovulation is not clear, but it appears to act at the ovarian level. The evidence indicates that sequential RU486/progestin treatment could be developed to result in suppression of follicular growth and ovulation.

Adult↗
PubMed1990

Accelerated dissolution of luteal-endometrial integrity by the administration of antagonists of gonadotropin-releasing hormone and progesterone to late-luteal phase women.

Sequential blockade of gonadotropin-releasing hormone (GnRH) and progesterone (P) receptors by potent antagonists (Nal-Glu GnRH antagonist and RU486) was conducted in late-luteal phase women to develop a once-a-month birth control method by timed advancement of ongoing luteolysis and endometriolysis. Hormonal dynamics and timing of uterine bleeding during the antagonists' imposed luteal-follicular transition were compared with spontaneous (1st to 2nd) and recovery (2nd to 3rd) cycles in 10 normally cycling women. Serum luteinizing hormone (LH) and follicle-stimulating hormone levels declined (47 +/- 4.3% and 24 +/- 3.0%, respectively) by 24 hours after Nal-Glu injection, which accelerated the ongoing luteolytic process, as evidenced by more rapid declines of serum concentrations of estradiol, P, and ir-inhibin, as compared with the corresponding control cycle. This was accompanied by the prompt (16 +/- 3.2 hours after RU486) onset of a single episode of uterine bleeding, which was advanced by 2 days. Whereas the luteal phase length was foreshortened by 2 days, the subsequent follicular phase duration was prolonged by 2 days with a normal sequence of follicular maturation, LH surge, and luteal function during the recovery cycle. We conclude that the late-luteal sequential administration of antagonists of GnRH and P resulted in acceleration of the ongoing luteolytic and endometriolytic processes without functional alterations of the subsequent cycle.

Adult↗