Low-dose mifepristone 200 mg and vaginal misoprostol for abortion

The objectives of this study were to determine the effectiveness, side effects, and acceptability of one-third the standard 600 mg dose of mifepristone (200 mg) to induce abortion. A prospective trial at seven sites enrolled women > or = 18 years, up to 8 weeks pregnant, and wanting an abortion. The women received 200 mg mifepristone orally, self-administered 800 micrograms misoprostol vaginally at home 48 h later, and returned 1-4 days later for ultrasound evaluation. Surgical intervention was indicated for continuing pregnancy, excessive bleeding, persistent products of conception 5 weeks later, or other serious medical conditions. Of the 933 subjects, 906 (97%) had complete medical abortions, 22 had surgical intervention, two were protocol failures, and three were lost to follow up. Of the 746 subjects who had no or minimal bleeding before misoprostol, 80% bled within 4 h and 98% within 24 h of using misoprostol. By day 7, 95% of women had a complete abortion. Side effects were aceptable in 85% of subjects, and 94% found the procedure acceptable. Low-dose mifepristone followed by vaginal misoprostol was highly effective as an abortifacient.

Preliminary report on the treatment of endometriosis with low-dose mifepristone (RU 486)

OBJECTIVE

We have previously shown that treatment with mifepristone, 50 to 100 mg daily, results in amenorrhea, anovulation, and symptomatic improvement in women with endometriosis. In this study we lowered the dose to 5 mg daily to determine whether clinical efficacy is altered without other adverse actions.

STUDY DESIGN

After a baseline cycle, seven women with endometriosis were given mifepristone, 5 mg daily, for 6 months. Daily symptom inventories were recorded. Laparoscopy was performed during the sixth month of therapy.

RESULTS

Pelvic pain improved in six of seven patients. Cyclic bleeding ceased in all patients, but four of the seven patients complained of irregular bleeding. Surgical staging at the conclusion of the study (five of seven patients) did not detect a change in endometriosis.

CONCLUSIONS

Mifepristone, 5 mg daily, resulted in symptomatic improvement, but did not stabilize the endometrium. From our experience with three doses of mifepristone, we would recommend a dose of 50 mg be used for continued investigations.

Vaginal misoprostol administered at home after mifepristone (RU486) for abortion

BACKGROUND

There have been no US studies published on the effectiveness, safety, time to bleeding, and acceptability of misoprostol administered by vagina at home and repeated, if needed, after mifepristone was administered for abortion in women up to 8 weeks pregnant.

METHODS

A prospective trial was conducted with women up to 8 weeks pregnant wanting an abortion. After receiving mifepristone 600 mg orally, subjects self-administered vaginal misoprostol 800 micrograms at home 2 days later. Subjects returned within 7 days, and if the gestational sac was still present on ultrasound, a repeat dose of misoprostol was administered in the office. Subjects completed a daily symptom log and a questionnaire on the acceptability of the procedures.

RESULTS

Of the 166 subjects, 163 (98%) had a complete medical abortion. Three subjects presented with persistent bleeding and an incomplete abortion from 27 to 35 days after taking mifepristone and required surgical intervention. Vaginal spotting or bleeding occurred in 104 (62%) subjects before taking misoprostol, and 18 (11%) did not use misoprostol. Bleeding occurred on average 3.5 hours (SD, 3.2) after taking misoprostol. Six (4%) subjects required a second dose of misoprostol. Gastrointestinal side effects were common, mild, and brief. One hundred fifty-nine (96%) subjects agreed that the procedure went well, and 146 (90%) agreed that home administration of misoprostol was acceptable.

CONCLUSIONS

Two days after taking mifepristone, misoprostol administered by vagina was found to be safe, highly effective, and acceptable to women. Since only 6 subjects needed a second dose of misoprostol, conclusions about repeat doses are not possible. This procedure is a promising alternative to surgical abortion.

Mifepristone: a potential contraceptive

Use of standard estrogen-progestin contraception remains problematic in several subgroups of patients (e.g., those in whom exogenous estrogens are contraindicated, such as survivors of hormone-dependent cancer, or patients with endometriosis or uterine fibroids). In addition, the postcoital contraception, even if already available, remains at least underused. Additionally, continuous intake of contraceptive steroids is under increasing scrutiny. Would antiprogestins, and specifically the applications of mifepristone such as the ones reviewed in this article offer significant improvements at such problematic occasions? The most attractive novel contraceptive application of mifepristone is that of emergency postcoital contraception after unprotected intercourse. In addition, various options in the endometrial category, specifically those requiring drug administration only during a limited time, might be used in the future. Mifepristone might offer contraceptive and therapeutic relief to patients suffering from endometriosis or uterine fibroids, both conditions that have been shown to benefit from mifepristone therapy. However, the use of mifepristone in contraceptive preparations that are widely available would pose an additional problem of possible misuse of the compound, the reason for currently limiting access to mifepristone. However, such risk should be easily avoidable in the case of postcoital contraception in which only one dose of mifepristone is needed. Regarding the future of mifepristone, and more broadly that of antiprogestins in contraception, the authors believe that they will have a place in the future contraceptive armament. As already emphasized, the strongest clinical areas are those of immediate postcoital and endometrial contraception. Additional studies evaluating parenteral modes of administration, the long-term endometrial effects, and safety and metabolic effects of prolonged antiprogestin administration are needed before mifepristone can be considered a part of the contraceptive arena.

Knowledge and perceptions of medical abortion among potential users

Nearly two-thirds of 73 women aged 18-34 who participated in focus groups on medical abortion conducted in three cities had heard about this new abortion method, but only a few could describe it accurately. Once the method was described to them, they cited its potential advantages over vacuum aspiration as being fewer major complications, the absence of surgery, a greater "naturalness," and its use earlier in pregnancy. Women listed as disadvantages the multiple visits needed for medical abortion, the unknown aspects of the new technology, especially regarding the expulsion of the conceptus, and concern that mifepristone would make an abortion too easy and lead some women to take the decision lightly. More than one-third of discussants said they would choose mifepristone if the method were available.

A comparative analysis of fall in haemoglobin following abortions conducted by mifepristone (600 mg) and vacuum aspiration

We compared post-abortion metrorrhagia in 185 women who used the mifepristone (600 mg) plus sulprostone (250 micrograms) drug combination and in 196 women who underwent vacuum aspiration. The patients were monitored for a 2 week period, with haemoglobin being measured on the day of the abortion and 2 weeks later. The women who had used the drug combination experienced a mean fall of 0.7 g/dl in haemoglobin (36% lost > 1 g/dl and 8% > 2 g/dl); haemoglobin concentrations remained stable in women who had had vacuum aspiration.

Further acceptability evaluation of RU486 and ONO 802 as abortifacient agents in a Chinese population

Of 144 consecutive women who requested early induced abortion, 99 (68.7%) and 45 (31.3%) women chose RU486 combined with ONO 802 (medical method) and suction evacuation (surgical method), respectively. Logistic regression analysis of covariates showed that age and marital status were significantly correlated with the acceptability and hence the choice of the medical method. There were also more working women in this medical group. Previous experience of induced abortion had no influence on the current choice of the abortion method. This group of women appeared to have a tendency of treating their disease with medication rather than with surgery if the condition would allow. They expressed fear about surgery. The long induction-abortion interval of three days will have to be tolerated, but the duration of bleeding should be minimised in order to improve the acceptability of the drug. RU486 is an alternative abortion method which should be made widely available.

Induction of abortion in early pregnancy with mifepristone in conjunction with gemeprost

This study was performed to investigate the efficacy of oral mifepristone and vaginal gemeprost for termination of early pregnancy. Eighty women requesting first trimester abortion and with amenorrhea of less than 56 days were included. Gestational age was confirmed with ultrasonography. Mifepristone was administered as a single 600 mg dose followed after 48 hours by a vaginal pessary containing 1 mg gemeprost. One woman did not return for gemeprost and later had a vacuum aspiration performed. There was complete abortion in all remaining women. No serious side effects were registered and the number of women requiring opioid analgesia was low (8%). The conclusion is that this treatment is a genuine alternative to vacuum aspiration but medical supervision is necessary for some time after gemeprost administration.

Effect of the progesterone antagonist RU486 on human myometrial spontaneous contractility and PGI2 release

We studied the effect of antiprogesterone RU 486 on spontaneous uterine contractility and PGI2 release with human myometrial strips superfused "in vitro". A decrease of PGI2 release into the superfusion medium was observed after 20 min superfusion. The inhibition was dose-dependent and reversible. After 20 min washing with tyrode medium without RU 486, the uterine strips recovered their initial rate of release. R5020, a progesterone agonist, did not affect PGI2 release nor dexamethasone and testosterone. Parallel to the decrease of PGI2 observed during RU 486 superfusion, the uterine spontaneous contraction frequency decreased, while the amplitude and duration of contractions increased. The alteration of uterine contractility was also rapid, dose-dependent and reversible. Modification of uterine strip spontaneous contractility, similar to those induced by RU 486, were also observed with superfusions of R5020 at concentrations as low as 10(-9)M, dexamethasone (10(-8)M), but not with superfusions of testosterone. These observations are not in favour of a progesterone-receptor mediated effect of RU 486 in our model. The mechanism of action may be related to the antiprogesterone specific structure i.e. the bulky substituent at the C-11 position. The RU 486 effect on uterine strip contractility, mimicked by other steroids, could point to a non-specific lipid/membrane interaction. However, the fact that testosterone did not affect motility, may indicate a possible specificity of steroids having a 3 oxo pregnene structure.

Mifepristone (RU 486) compared with high-dose estrogen and progestogen for emergency postcoital contraception

BACKGROUND

Mifepristone (RU 486) is a synthetic steroid with potent antiprogestational and antiglucocorticoid properties that provides an effective medical method of inducing abortion in early pregnancy. Since progesterone is essential for implantation, we tested the use of mifepristone for emergency postcoital contraception.

METHODS

We studied 800 women and adolescents requesting emergency postcoital contraception who had had unprotected intercourse within the preceding 72 hours. A total of 398 women and adolescents were randomly assigned to treatment with 100 micrograms of ethinyl estradiol and 1 mg of norgestrel, each given twice 12 hours apart (standard therapy), and 402 women and adolescents were randomly assigned to receive 600 mg of mifepristone.

RESULTS

None of the women and adolescents who received mifepristone became pregnant, as compared with four of those who received standard therapy; the difference in failure rates between the two regimens was not statistically significant. The number of pregnancies in each group was significantly lower than the number expected according to calculations based on the day of the cycle during which intercourse had taken place (P less than 0.001). In many subjects the stage of the cycle as calculated by menstrual history was inconsistent with measurements of plasma progesterone or urinary pregnanediol excretion. The subjects treated with mifepristone reported less nausea (40 percent vs. 60 percent) and vomiting (3 percent vs. 17 percent) on the day of treatment, as well as lower rates of other side effects, than the subjects treated with the standard regimen, but they were more likely to have a delay in the onset of the next menstrual period (42 percent vs. 13 percent).

CONCLUSIONS

Mifepristone is a highly effective postcoital contraceptive agent that, if used more widely, could help reduce the number of unplanned and unwanted pregnancies.

A randomized clinical trial of mifepristone (RU486) for induction of delayed menses: efficacy and acceptability

Mifepristone (RU486) should be useful for inducing menstrual bleeding in women with menses delayed up to 10 days. We evaluated this potential use for "menstrual regulation" in a randomized clinical trial with 16 women, half of whom received a single 600 mg dose and half of whom received a placebo. Four of eight women in each treatment group proved to be pregnant. Seven of eight who received mifepristone were not pregnant at two-week follow-up, in contrast to four of eight who received the placebo (p = 0.15). Mifepristone may hold promise for "menstrual regulation" for women who do not have access to medical confirmation of pregnancy or who choose not to have this determination made.

Mifepristone (RU 486) treatment of meningiomas

Meningiomas are common brain tumours which are generally benign, well circumscribed and slow growing. In a minority of patients complete surgical removal is not possible and re-growth of tumour tissue is a major clinical problem. Most meningiomas contain progesterone receptors. The anti-progestational drug mifepristone (RU 486) binds to these receptors. Ten patients were treated with 12 recurrent or primary "inoperable" meningiomas, all of whom had shown recent neuroradiological and/or ophthalmological evidence of tumour growth. They received 200 mg mifepristone daily for 12 months. Most patients initially had complaints of nausea, vomiting and/or tiredness. In four patients prednisone (7.5 mg/day) was given after which these side-effects subsided. CT scan analysis of tumour size, showed progression of growth of five meningiomas in four patients, stable disease in three patients with three tumours and regression of four tumours in three patients. A decrease in the complaints of headache and an improved general well being was observed in five patients. Two patients died during the treatment period from unrelated causes. Mifepristone treatment resulted in control of tumour growth (= stable disease) in six of 10 patients who had shown recent evidence of tumour growth. In three of these six patients consistent tumour shrinkage was observed.

A pilot study of acceptability of RU486 and ONO 802 in a Chinese population

RU486 and ONO 802 in combination have been shown to be effective in early termination of pregnancy. Anecdotal information suggests that Chinese women have been using herbs to induce abortion, believing that such medication and means of abortion is less harmful to the body than surgery. Hence, a medical means of abortion using RU486 and ONO 802 may be the method of choice for some Chinese women. A pilot study involving 42 Chinese women in Hong Kong was conducted to explore the reasons for acceptance or refusal of RU486 and ONO 802 as abortifacient agents. It was found that more single women chose the medical method for abortion, the main reasons being fear of trauma to the body due to surgery and the feeling of having undergone menstrual regulation rather than having had an abortion with the medical method. Those who refused the treatment were worried about the efficacy and side effects of the new drugs and the long induction-abortion interval. There were 3 failures in the medical group of 23 women. All these 23 women were gland they had chosen the medical abortion method. Twenty-one out of the 23 women said they would choose the same abortion method again. The practice of the use of Chinese herbs was not more common in this group of women as compared to women who did not choose this method of abortion.

Pre-operative cervical preparation before first trimester vacuum aspiration: a randomized controlled comparison between gemeprost and mifepristone (RU 486)

OBJECTIVE

To compare the effectiveness of 200 mg mifepristone with 1 mg gemeprost vaginal pessary in achieving cervical dilatation and softening ('priming') before late first trimester pregnancy vacuum aspiration.

DESIGN

A randomized, operator blind, placebo controlled trial.

SETTING

UK teaching hospital.

SUBJECTS

90 primigravid women with 63-91 days amenorrhoea and ultrasonically confirmed single living fetus of correct size for gestational age.

INTERVENTIONS

The women were allocated to receive 200 mg mifepristone orally or an identical oral placebo 36 h before operation or 1 mg gemeprost vaginal pessary 3-4 h preoperatively.

MAIN OUTCOME MEASURES

Onset of new symptoms following drug administration, a proven objective measure of the force required to dilate the cervix, and estimated intraoperative blood loss.

RESULTS

There were no significant differences in the baseline cervical dilatation, the force required to dilate the cervix or the volume of intraoperative blood loss between the active treatment groups. Both drugs were significantly more effective than placebo. Significantly fewer women in the mifepristone group had adverse side effects than in the gemeprost group.

CONCLUSIONS

Mifepristone is a highly effective cervical priming agent, and has the advantages of being an oral preparation associated with few side effects.

Pretreatment of the primigravid uterine cervix with mifepristone 30 h prior to termination of pregnancy: a double blind study

OBJECTIVE

To determine the effect of the antiprogestogen mifepristone (RU 486) on cervical resistance before first trimester termination of pregnancy.

DESIGN

Prospective double blind randomized placebo controlled study.

SETTING

Department of gynaecology in a university teaching hospital, Sheffield.

SUBJECTS

80 Primigravid women greater than 18 years of age, undergoing termination of pregnancy at between 7 and 13 weeks gestation.

INTERVENTIONS

A single dose of 600 mg of mifepristone or placebo given orally 30 h before termination of pregnancy under general anaesthesia.

MAIN OUTCOME MEASURES

Cervical resistance to dilatation.

RESULTS

Pretreatment with mifepristone significantly reduced the amount of force required to dilate the cervix to 10 mm. In comparison with placebo, the mean sum of the peak forces obtained with dilators 4 to 10 mm was reduced from 84.3 N (SD 29.7) to 46.0 N (SD 26.7). Two women in the treated group had a cervical resistance of greater than 100 N compared with nine women in the placebo group (RR 0.18, 95% CI 0.04-0.89). The 8 mm dilator could be passed with less than 5 N force in 16 women (43%) in the treated group compared with none in the placebo group. Women in the active treatment group had more preoperative pelvic pain and vaginal bleeding but less postoperative pain.

CONCLUSION

Mifepristone significantly reduces cervical resistance in the first trimester of pregnancy and produces minimal side effects.

The endocrine effects of long-term treatment with mifepristone (RU 486)

Mifepristone (RU 486) is a compound with progesterone as well as cortisol-blocking activities. We investigated the endocrine effects of long-term therapy of 10 patients with meningiomas with 200 mg mifepristone daily for 1 yr. Most patients initially complained of nausea, vomiting, and/or tiredness. In four patients prednisone (7.5 mg/day) had to be given simultaneously in order to overcome these side-effects. In retrospect those patients who presented with the most severe side-effects showed the most rapidly occurring activation of the hypothalamo-pituitary-adrenal-axis, as measured by an increase of circulating cortisol levels as well as of urinary cortisol excretion. Therapy with RU 486 activated the hypothalamo-pituitary-adrenal axis, resulting in a resetting of this system at a higher level at which the diurnal rhythm and the responsiveness to CRH stimulation were maintained, whereas the sensitivity to dexamethasone had diminished. Secondarily the production of androstenedione and estradiol increased considerably. These endocrine changes were caused by the induction of partial cortisol receptor resistance during therapy with RU 486. The compensatory overproduction of androgens and consequently of estrogens during long-term RU 486 therapy might limit its use as a single treatment in the treatment of estrogen-dependent cancer.

The effects of the antiprogesterone RU486 (Mifepristone) on an endometrial secretory glycan: an immunocytochemical study

OBJECTIVE

To examine the effects of progesterone (P) receptor blockade by RU486 (Mifepristone; Roussel-Uclaf, Paris, France) on a secretory endometrial glycan recognized by monoclonal antibody D9B1.

DESIGN

Retrospective comparison of endometrial biopsies from treated and untreated women from 2 to 8 days after the luteinizing peak (LH) peak.

SETTING

Infertility clinic, Jessop Hospital for Women, Sheffield.

PATIENTS

Twenty-two normal fertile women received the RU486. A control group of 44 normal fertile women were also assessed.

INTERVENTIONS

RU486 was administered to 22 normal women during the first half of the luteal phase and an endometrial biopsy examined 3 days later.

MAIN OUTCOME MEASURES

Immunohistochemistry was used to assess the production and secretion of the D9B1 epitope.

RESULTS

When the drug was given 2 days after the LH peak, it prevented appearance of the epitope. When RU486 was administered 5 days after the LH peak, epitope already present in gland cells was subsequently secreted.

CONCLUSIONS

These data suggest that production of the sialo-oligosaccharide is P-dependent, but secretion through established intracellular pathways is P-independent.

Agonistic and antagonistic activities of RU486 on the functions of the human progesterone receptor

RU486 induced the binding to a palindromic progestin responsive element (PRE) in vitro of homo- and heterodimers of the human progesterone receptor (hPR) isoforms A and B, present in T47D breast cancer cells or in HeLa cells transiently expressing the recombinant proteins. The resulting complexes were indistinguishable from those induced with the agonist R5020 with respect to specificity, affinity and stability. Ligand exposure was a necessary prerequisite to observe PR/PRE complexes. Antagonist-induced complexes migrated more rapidly during electrophoresis than agonist-induced ones, and no 'mixed' PR/RU486-PR/R5020 complexes were observed, suggesting that the dimerization interfaces of agonist- and antagonist-bound molecules are non-compatible. The analysis of a series of deletion mutants and chimeric receptors revealed the presence of two transcription activation functions (TAFs), located in the N-terminal region A/B (TAF-1) and the hormone binding domain (TAF-2). In the presence of agonists, both TAFs were active in HeLa cells. In the presence of RU486 TAF-2 was inactive, while TAF-1 within the hPR form B/RU486 complex activated transcription from a reporter gene containing a single palindromic PRE. We consider this to be the most convincing evidence that the receptor/RU486-complex does in fact bind to PREs in vivo. No transcriptional activation was observed in the presence of RU486 from a reporter gene containing the complex MMTV-LTR PRE. In contrast to hPR form B, form A was not able to activate transcription from PRE/GRE-tk-CAT in the presence of RU486. In vivo competition between hPR/RU486 and either cPR/R5020 or the human glucocorticoid receptor/dexamethasone (hGR/Dex) complex further supported that hPR/RU486 bound in vivo to its cognate responsive element. Indeed, the observed inhibition of transcription was shown to be due to competition for the MMTV PRE, since no transcriptional interference by the hPR/RU486 was observed, and since no heterodimers were formed between hPR/RU486 and cPR/R5020 or hGR/Dex. That the ligand-free hPR, however, was unable to compete, demonstrated that ligand binding is the prerequisite for DNA binding of hPR in vivo.

Effect of chronic treatment with the glucocorticoid antagonist RU 486 in man: toxicity, immunological, and hormonal aspects

Suppression of immune function was traditionally thought to occur only with pharmacological levels of glucocorticoids. However, recent studies in rodents have suggested that glucocorticoids exert tonic antiinflammatory/immunosuppressive effects even at basal nonstress concentrations. To examine whether basal glucocorticoid secretion modulates immune function in man we employed the specific glucocorticoid receptor antagonist RU 486. If a tonic level of inhibition of the immune system by basal glucocorticoid levels was present, then a potentiation or enhancement of immune function might evolve in the absence of glucocorticoid action. To examine this hypothesis, we studied 11 healthy male normal volunteers who received RU 486 (10 mg/kg.day) or placebo vehicle, divided into 2 daily oral doses, for 7-14 days. Blood samples were collected every 2 days for measurement of plasma ACTH and cortisol concentrations along with 24-h urine samples for measurement of 17-hydroxysteroid and free cortisol excretion. Complete and differential blood counts, erythrocyte sedimentation rates, C-reactive protein, antinuclear antibodies, rheumatoid factor, and quantitative immunoglobulins were also determined at 2-day intervals. Leukocytes were obtained by leukopheresis for phenotypic characterization and functional analysis before and 7 days after the initiation of RU 486 or placebo therapy. Blockade of cortisol receptors with RU 486 was associated with marked compensatory elevations of plasma ACTH and cortisol and increases in 24-h urinary excretion of 17-hydroxysteroids and free cortisol. Unexpectedly, 8 of the 11 subjects developed generalized exanthem after 9 days of RU 486 treatment. One subject developed symptoms and signs consistent with the diagnosis of adrenal insufficiency. Total white blood cell counts, absolute lymphocyte, neutrophil and eosinophil counts, erythrocyte sedimentation rate, and quantitative immunoglobulins did not change with RU 486 therapy. Similarly, T-, B-, and natural killer cell subsets did not change during RU 486 treatment. Furthermore, functional evaluation of lymphocyte cytotoxicity and proliferation revealed no changes. We conclude that administration of high doses of RU 486 to normal volunteers does not result in measurable enhancement of immune function. This suggests that in man, glucocorticoids may not exert a tonic inhibitory effect on the immune system as they appear to do in rodents. Alternatively, the compensatory increase in endogenous cortisol may obviate any effect of the glucocorticoid antagonist on the immune system.(ABSTRACT TRUNCATED AT 400 WORDS)

Peptide-containing nerves in the human pregnant uterine cervix: an immunohistochemical study exploring the effect of RU 486 (mifepristone)

The presence of several neuropeptides (neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), calcitonin gene-related peptide (CGRP), substance P (SP), galanin (GAL), enkephalin (ENK), somatostatin (SOM) was established in the early pregnant human cervix using indirect immunofluorescence immunohistochemistry. Several peptides (VIP, NPY, CGRP, GAL) were present both in free nerves among smooth muscle cells and around blood vessels. Others (SP, SOM) were only seen as single varicosities among smooth muscle cells. Randomized treatment of patients with RU 486 (mifepristone) prior to surgical sampling revealed no clearcut differences in peptide immunoreactivities. After RU 486 treatment, however, there was a tendency towards a decrease of NPY- and VIP-immunoreactivity, and an increase of CGRP-immunoreactivity.

The use of mifepristone prior to prostaglandin-induced mid-trimester abortion

It has previously been established that the administration of mifepristone prior to prostaglandin-induced second trimester termination of pregnancy significantly reduces the induction to abortion interval. In this study, mifepristone (600 mg) was administered 24, 36 and 48 h prior to extra-amniotic infusion of prostaglandin in an attempt to elucidate the optimal time interval. There was a significant reduction in the induction to abortion interval, dose of prostaglandin required and attendant side effects in all three treated groups compared to controls. However, there was no significant difference among the treatment groups, despite evidence of increased uterine activity 36 h following mifepristone administration. No bleeding was observed prior to prostaglandin infusion in any of the groups and it is suggested that mifepristone could be administered safely prior to hospital admission for termination.

Effect of mifepristone on dilatation of the pregnant and non-pregnant cervix

The effect of the progesterone antagonist mifepristone on the cervix was investigated in two randomised double-blind placebo-controlled trials, the first in 30 women undergoing first trimester surgical termination of pregnancy and the second in 30 non-pregnant premenopausal women. 600 mg mifepristone, given orally 48 h before surgery, increased the mean preoperative cervical dilatation in both pregnant and non-pregnant treatment groups and also reduced the force required to dilate the pregnant and non-pregnant cervix.

Long-term effects of progestin and RU 486 on prolactin production and synthesis in human endometrial stromal cells

Previous studies have shown that the production of prolactin (PRL) is increased in human endometrial stromal cells cultured with medroxyprogesterone acetate (MPA) for 3-5 days. In the present study, we have investigated the effect of prolonged treatment of progestin and anti-progestin, RU 486, on the production and synthesis of PRL. Stromal cells were isolated from human endometrium obtained from non-pregnant women and cultured for 20-30 days in medium RPMI 1640 with 2% fetal calf serum or supplemented with MPA, RU 486, alone or in sequence. The PRL content in medium was measured by radioimmunoassay. The production rate was estimated from the PRL content in medium accumulated in 24 h. The PRL production rate was progressively increased in stromal cells continuously treated with MPA for 30 days (greater than 100-fold over the control value, i.e. 0-0.01 microgram/0.1 mg cell DNA/day). RU 486 alone had no effect on the production of PRL. However, the production of PRL was increased by MPA in stromal cells pretreated with RU 486 indicating that the effect of RU 486 is reversible. When stromal cells were treated with MPA and RU 486 sequentially, RU 486 stimulated the PRL production (approximately 2-fold over the MPA-treated cells) for 2-3 days and then reduced to basal levels over a 5-day period. The stimulatory and inhibitory effects of RU 486 on PRL production in stromal cells pretreated with progestin was also observed in the rate of synthesis of PRL estimated by incubating the stromal cells with [35S]methionine and immuno-isolating the [35S]PRL with anti-PRL.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of oral prostaglandin E2 on uterine contractility and outcome of treatment in women receiving RU 486 (mifepristone) for termination of early pregnancy

It has been shown that the antiprogestin RU 486 (mifepristone) increases the sensitivity of the early pregnant human uterus to the stimulatory action of synthetic prostaglandin E (PGE) analogues. To examine if RU 486 also increases uterine sensitivity to the naturally occurring PGE2 given orally, two investigative approaches were used in the present studies: (i) direct registration of uterine contractions before and after PGE2 administration in untreated and RU 486-treated early pregnant women; and (ii) a double-blind, randomized, controlled efficacy trial involving treatment of pregnant women (amenorrhoea of less than or equal to 49 days) with RU 486 (25 mg twice daily for 4 days) and PGE2 (1 mg once or twice) or placebo on the last day of RU 486 treatment. The results indicate that oral PGE2 at the doses employed had little or no stimulatory effect on uterine contractility and that it did not improve the rate of complete abortion achieved with RU 486 alone. Overall, 25 of 42 women (59%) had a complete abortion, 15 women (36%) did not abort and the remaining two had incomplete abortions. Women with complete abortions had significantly lower pretreatment levels of progesterone and a longer duration of induced bleeding than those who did not abort. Thus oral PGE2, when given in clinically acceptable doses, is not a suitable alternative to synthetic PGE analogues for use in combination with RU 486 for termination of early pregnancy.

Termination of early pregnancy with RU 486 (mifepristone) in combination with a prostaglandin analogue (sulprostone)

The antiprogestin RU 486 (mifepristone) has been shown to induce abortion when administered in early pregnancy, but the rate of incomplete abortion is high, around 40%. As blockage of the progesterone receptor increases the myometrial sensitivity to prostaglandins, a combination of RU 486 and a prostaglandin E2-analogue was tested for termination of pregnancy. One hundred and sixteen women, with a gestational length of less than 49 days from the first day of the last menstrual period, were treated with a daily dose of 50 or 100 mg RU 486 for 3 to 6 days, complemented with an intramuscular dose of 0.25 mg sulprostone (16-phenoxy-PGE2-sulfonylamide) on the last day of RU 486 treatment. The results confirmed that a reduction of treatment duration to 3 days is just as effective for inducing abortion (91% complete abortion) as a 4-6-day treatment regimen (95% complete abortion). Six patients had an incomplete abortion and in one the pregnancy continued unaffected. Side effects included intense uterine pain after the prostaglandin administration (16%), vomiting associated with the antiprogestin intake (9%) and after the prostaglandin administration (9%). One woman needed emergency curettage due to heavy bleeding. Six percent of the treated patients had a decrease in hemoglobin exceeding 20 g/l during the first week but no patient needed blood transfusion. No serious side effects were recorded.

Contragestion with late luteal administration of RU 486 (Mifepristone)

The efficacy and tolerance of RU 486 prescribed as a late luteal contragestive agent have been evaluated in 139 women at risk of pregnancy. They were given 400 or 600 mg of RU 486 once on the day before the expected menses. Among these women, 48 (34.5%) were pregnant (positive plasma beta-human chorionic gonadotropin, [beta-hCG]) at the time of RU 486 intake. Bleeding occurred in all but six women. An ongoing pregnancy after treatment was found in nine cases (failure rate, 9/48, 18.8%), which was subsequently terminated by surgical procedure in all cases. There was no disturbance in the menstrual cycle, and the tolerance was very satisfactory. In conclusion, this method is acceptable for women at risk of pregnancy in whom other usual postcoital contraceptive methods cannot be prescribed.

Late luteal phase administration of RU486 for three successive cycles does not disrupt bleeding patterns or ovulation

RU486, a 19-nor steroid, binds with high affinity to the receptors for progesterone and glucocorticoids, blocking the actions of these hormones on their target tissues. We conducted studies to determine whether RU486 administered at the end of the luteal phase would disturb the menstrual rhythm, ovulation, or hormonal parameters in the treatment and post-treatment cycles. The first study was done in six surgically sterilized women during two consecutive cycles. RU486 [17 beta-hydroxy-11 beta-(4-dimethylaminophenyl)17 alpha-(1-propynyl)estra-4,9-dien-3-one; 100 mg/day] was given for 4 consecutive days, commencing on days 23-27 of the first cycle. Menstrual bleeding occurred by the second day of RU486 administration in all women and was indistinguishable from their usual bleeding pattern. The onset of this bleeding was advanced by RU486 administration, since it entailed shortening of the luteal phase with prolongation of the following follicular phase. Serum LH, FSH, estradiol, and progesterone levels were normal in five of the six women in both the treatment and posttreatment cycles. The second study was conducted in 10 women who were not exposed to the risk of pregnancy. RU486 (100 mg/day) was given for 4 consecutive days, commencing 4 days before their expected menses for 3 successive cycles, preceded and followed by 2 placebo-treated cycles. Bleeding patterns were indistinguishable during the RU486 and placebo cycles. Late luteal phase administration of RU486 consistently produced menstrual bleeding within 1-3 days of drug administration. Daily early morning urinary LH excretion in 6 women and estrone glucuronide and pregnanediol glucuronide excretion in 5 women during both placebo and RU486 cycles were consistent with luteinization, suggesting ovulation and appropriate corpus luteum function. We conclude that RU486 has no major effect on menstrual cycle events if given at the time of the natural progesterone withdrawal that occurs before menses in nonpregnant women.