Once-a-month treatment with a combination of mifepristone and the prostaglandin analogue misoprostol

In this two centre study, the efficacy of 200 mg mifepristone orally followed 48 h later by 0.4 mg misoprostol orally for menstrual regulation was investigated. The dose of mifepristone was taken the day before the expected day of menstruation. Each volunteer was planned to participate for up to 6 months. A plasma beta human chorionic gonadotrophin (HCG) was measured on the day of mifepristone intake. The study was disrupted prematurely due to low efficacy. In 125 treatment cycles the overall pregnancy rate was 17.6% (22 pregnancies) and the rate of continuing pregnancies (failure) was 4.0%. Eight women discontinued the study due to bleeding irregularities which were seen in 15 cycles (12%). These effects on bleeding pattern made the timing of treatment day difficult. Late luteal phase treatment with a combination of mifepristone and misoprostol is not adequately effective for menstrual regulation.

Identification of choriocarcinoma by the hCG beta-to-hCG proportion in patients with delayed diagnosis caused by contraceptive use

The use of contraceptives, especially subdermal implants and levonorgestrel-containing intrauterine device (IUD), often cause irregular bleeding. Thus, they may mask unsuspected choriocarcinoma, which also often presents with abnormal bleeding. Choriocarcinoma is mostly curable with combination chemotherapy, but delayed diagnosis can lead to treatment failure. Two cases of choriocarcinoma with considerable delay in diagnosis, due partly to contraceptive use, are reported. The proportion of human chorionic gonadotropin-beta (hCG beta) and total hCG immunoreactivity showed that the proportion of hCG beta was elevated at presentation in both cases.

Change in serum beta-human chorionic gonadotropin after abortion with methotrexate and misoprostol

OBJECTIVE

The purpose of this study was to determine the normal beta-human chorionic gonadotropin change within 24 hours after a medical abortion. Because a medical abortion creates a "miscarriage," these data can represent the serum beta-human chorionic gonadotropin changes that would occur with a complete spontaneous abortion. Knowledge of normal beta-human chorionic gonadotropin changes after a spontaneous abortion may help to differentiate within a 24-hour period a complete from an incomplete spontaneous abortion or an ectopic pregnancy.

STUDY DESIGN

Data from recent trials that used methotrexate and misoprostol for abortion at < or = 56 day's gestation were reviewed. Patients from each of four trials were included in this analysis if (1) they received both methotrexate intramuscularly and misoprostol vaginally and (2) they had serum beta-human chorionic gonadotropin levels drawn on both the day of misoprostol administration and the next day.

RESULTS

The change in serum beta-human chorionic gonadotropin was evaluated in 86 patients. Subjects who had a complete abortion after receiving methotrexate and a single dose of misoprostol had a decline in serum beta- human chorionic gonadotropin of 66% +/- 8%. All other subjects had a decline of 25% +/- 19% (p=0.0001).

CONCLUSIONS

An aborting pregnancy, if the abortion has occurred, should have a beta-human chorionic gonadotropin decrease of at least 48% within approximately 24 hours. This decline, however, does not guarantee that the abortion is complete. A patient with a serum beta-human chorionic gonadotropin level that has not declined by a minimum of approximately 50% over 24 hours is unlikely to have a complete abortion.

Vaccination for birth control

The global population is currently expanding at the unprecedented rate of nearly 1 billion per decade, with 94% of the increase occurring in the developing world. New methods of fertility regulation are urgently needed, and the development of birth control vaccines by active immunization against antigens specific for reproduction has made substantial progress during the last two decades. These vaccines are meant to have an outstanding impact on future control of worldwide population growth by providing safe, effective, long-lasting and reversible contraception. The most advanced of these vaccines are based on the placental pregnancy hormone human chorionic gonadotropin (hCG), and have already entered clinical trials. However, immunological cross-reactivity and lack of efficacy of anti-hCG antibodies seriously challenge this strategy. Conversely, efforts to understand the molecular events involved in the fusion of sperm and egg have led to the identification of new target structures for the development of fertility-regulating vaccines. Herein, we summarize the current state of birth control vaccines and discuss the risks and drawbacks of this approach to fertility regulation.

Methotrexate and misoprostol for abortion at 57-63 days gestation

Methotrexate and misoprostol have been shown in preliminary studies to be effective for abortion at < or = 56 days gestation with minimal side effects. RU-486 is used in combination with prostaglandin for abortion < or = 49 days gestation in France but < or = 63 days gestation in England. This pilot study was performed to evaluate if methotrexate and misoprsotol may also be effective up to 63 days gestation. Ten pregnant women between 57-63 days gestation were treated with methotrexate 50 mg/m2 intramuscularly followed 3 days later by misoprostol 800 micrograms vaginally. Abortion occurred in 6 women; abortion occurred in one of the women after a repeat dose of misoprostol 24 hours after the first dose. The remaining 4 women all had a surgical abortion. In the successfully treated women, vaginal bleeding lasted 14 +/- 4 (mean +/- standard deviation) days and serum beta-hCG was < or = 25 IU/L by 32 +/- 5 days after the methotrexate injection. No methotrexate side effects occurred. Methotrexate and misoprostol do not appear to be as effective for medical abortion between 57 and 63 days gestation as compared to < or = 56 days gestation.

The suitability of human chorionic gonadotropin (hCG)-based birth-control vaccines

It has been widely hoped that immunological methods of fertility regulation by active immunization against specific antigens of the oocyte, sperm, zygote and early embryo, and the placental pregnancy hormone human chorionic gonadotropin (hCG), will provide a means to control the problem of worldwide population growth. The most advanced candidate vaccines are based on hCG immunogens and have entered clinical trials. However, during the past few years, increasing evidence has emerged that the current approaches using hCG as the target molecule may have some major drawbacks. On the basis of their recent findings, Stephan Dirnhofer and colleagues raise doubts on the suitability, safety and efficacy of gonadotropin-based immunological contraceptive vaccines.

Vaccination for contraception

Vaccination for birth control has several advantages over currently available methods of family planning and should prove an attractive addition to the contraceptive armamentarium both in developing countries and in a developed country such as Australia. Concerns have been voiced by consumer health advocates that vaccines, like other long acting contraceptive methods, may be abused by health authorities in developing countries and by their use in vulnerable groups such as aborigines in our own country. These concerns need to be recognised and addressed. More difficult to accommodate are the anxieties expressed by feminist groups about the 'loss of control' and 'lack of body awareness' inherent in a method, such as a vaccine, that is relatively easily administered and has no overt side effects. There is no evidence that these concerns are shared by women in general. The antifertility vaccine that will most likely be applied first in family planning programmes is one directed against the pregnancy hormone hCG. A WHO vaccine directed against the C-terminal peptide of beta-hCG provokes a specific and safe immune response and will enter Phase 2 trials in Sweden this year. Subsequent developments with this vaccine will include the replacement of the current emulsion vehicle by a delivery system based on biodegradeable microspheres which will give a more sustained antigen release and duration of effectiveness.

Antibody response against three epitopic domains on human chorionic gonadotropin (hCG) in women and rodents immunized with a beta hCG-based immunocontraceptive vaccine

The antibody repertoire generated against human chorionic gonadotropin (hCG), following immunization with an immunocontraceptive vaccine based on the beta subunit of the hormone, in humans was compared with that generated in rats. Three epitopic domains represented by the beta hCG loop peptide 38-57, the carboxy-terminal peptide (CTP) 109-145, and a region defined by monoclonal antibody (MAb) 206 were probed. In both species, the titer of antibodies against the MAb 206-defined epitopic domain had a good correlation with the total anti-hCG antibody titers. However, the antibody response against the beta hCG loop peptide (38-57) was not observed in human subjects and there was a weak response against this peptide in rats. Despite the good anti-hCG antibody titers in all animals (n = 8), only two had antibodies against this domain. A good antibody response was observed against CTP in rats, whereas in humans this region was weakly immunogenic. Antibodies against CTP were detected in random samples in only 57% of the subjects and this response had no correlation with the total anti-hCG antibody titers. The high antibody response against CTP in rodents compared to humans may be due to its recognition as a foreign determinant. Our results demonstrate that contraception can be achieved in women despite a poor antibody response against the CTP (109-145) and a receptor binding domain (38-57) of beta hCG.

Immunization against HCG

The possibility of using the immune system to provide protection against an unwanted pregnancy has been postulated since the very early days of modern immunology. During the past two decades or more, a major goal-directed research effort, involving several independent groups of investigators, has been underway with the objective of developing birth control vaccines suitable for use by men and women at all stages of their reproductive lives. The most advanced work in this area is concerned with the development of a vaccine directed against human chorionic gonadotrophin (HCG), a hormone that is produced by the peri-implantation embryo and that is essential for successful implantation and the establishment of early pregnancy. These studies have reached the stage of clinical testing of a number of prototype vaccines based on different parts of the HCG molecule. No adverse side effects have been observed or reported in these clinical trials and larger scale clinical studies are being planned to assess further the safety, efficacy and acceptability of these preparations. Research is also underway to develop improved versions of these HCG vaccines that will offer 12-18 months protection following a single injection. The stage is set for the introduction, by the turn of this century, of the first totally new method of family planning in four decades.

IgG subclass distribution of anti-hCG and anti-diphtheria toxoid antibodies in women immunized with a beta-hCG based immunocontraceptive vaccine

IgG subclass distribution of antibodies against human chorionic gonadotropin (hCG) and diphtheria toxoid (DT) was determined in the sera of women recruited into Phase II clinical trials of a beta-hCG based immunocontraceptive vaccine. Serum samples from 30 different individuals were analyzed. Anti-hCG antibody response was predominantly of IgG1 subclass, with a mean titer of 537.94 +/- 560 antibody units (AU). The other 3 subclasses showed considerably lower mean levels (IgG2, 16.46 +/- 8.33; IgG3, 3.22 +/- 8.48; IgG4, 56.65 +/- 82.60 AU). A good correlation was observed between the anti-hCG IgG1 antibody titers (r = 0.57, P < 0.01) and the bioneutralization capacity of sera. However, bioneutralization capacity of the sera from subjects capable of inducing IgG4 response was not significantly different from subjects not showing IgG4 antibodies. Similarly, a dominant IgG1 response was observed against diphtheria toxoid (DT) which has been used as one of the carrier proteins in the vaccine.

Contraceptive vaccine development

Recent advances in antigen definition and production have made the development of a contraceptive vaccine more attainable. Such a vaccine must evoke an immune response that blocks an indispensable step in the reproductive process. Vaccine research involves many approaches to fertility prevention. Vaccines are being developed that could interrupt fertility by inhibition of gonadotrophin release, the function of follicle-stimulating hormone or the effects of human chorionic gonadotrophin (hCG); alternatively, they may prevent fertilization by interfering with the transport of spermatozoa or with sperm-zona pellucida binding. The most advanced prototype is a vaccine based on antibodies to beta hCG. Such vaccines are being studied for clinical efficacy. Many hurdles remain in contraceptive vaccine development. Since the antigens are peptides or small proteins, the resultant immune response is usually moderate, and better adjuvants and delivery systems must be developed to enhance and maintain the immune response. Improvement of the mucosal immune response may be necessary for vaccines incorporating sperm antigens. Research on vaccines that control fertility has resulted in a fascinating base of scientific knowledge that, it is hoped, can be converted into products that will allow another option for individuals who wish to control their fertility.

Methotrexate and misoprostol for early abortion

Methotrexate is cytotoxic to trophoblast and, in low doses, has minimal side effects. It is used to treat both gestational trophoblastic neoplasia and ectopic pregnancy. The cytotoxic effects of methotrexate on intrauterine trophoblast should be equivalent. To test this hypothesis, ten pregnant women, < 8 weeks' gestation were treated with methotrexate 50 mg/m2 intramuscularly followed 3 days later by misoprostol, a prostaglandin E1 analogue. The first 4 patients received misoprostol 600 micrograms orally; none aborted soon after the misoprostol. Two patients aborted 25 and 26 days after the methotrexate injection and two elected a suction abortion after 14 days (one by choice and one because the pregnancy was still viable). The last 6 patients received misoprostol 800 micrograms vaginally and aborted within 3-8 hours. One patient had an incomplete abortion requiring a suction curettage 34 days after the misoprostol. Vaginal bleeding for these 6 patients lasted an average of 29 +/- 11 days (range, 12-42 days). No methotrexate side effects were observed. Vaginal misoprostol (800 micrograms) was significantly more effective (p = 0.005) than oral misoprostol (600 micrograms) in effecting abortion after intramuscular methotrexate.

Sonographic assessment of ovarian and endometrial changes during long-term Norplant use and their correlation with hormonal levels

OBJECTIVE

To study the probability of ovulation and subclinical abortion during long-term use of Norplant and to assess the concomitant endometrial development.

DESIGN

This was a prospective nonrandomized comparative study. The ovaries and endometrium were assessed daily by ultrasonography during 59 menstrual cycles in 50 women who were using Norplant for > 1 year. Serum concentrations of E2, P, FSH, LH, pregnancy specific beta 1 glycoprotein (Sp1), and hCG were also daily measured. The findings were compared with those in 35 ovulatory cycles in normal fertile women not using contraception.

SETTING

Clients of the Family Planning Clinic of Assiut University Hospital (Norplant users) and the hospital women staff (controls).

RESULTS

Sonographic and hormonal evidence of ovulation were observed in one third of Norplant users; two of them resulted in conception. However, the majority of these ovulatory cycles showed low midcycle peaks of E2, FSH, and LH and evidence of luteal phase defect (LPD). Excessive follicular enlargement was observed in 46% of the cycles. Norplant users had significantly thinner endometrium that did not exhibit the normal phasic changes in sonographic texture. Apart from conceptive cycles, no rise in Sp1 or hCG was observed.

CONCLUSIONS

Norplant acts mainly by inhibiting ovulation, but when this occurs, it is associated with LPD and subnormal endometrial development. Subclinical abortion does not contribute to the contraceptive effect.

A birth control vaccine is on the horizon for family planning

Vaccines for control of fertility are likely to have an important impact on family planning methods. They are designed to act by mobilization of an internal physiological process and do not require external medication on a continuous basis. A number of birth control vaccines are at different stages of development, the most advanced being a vaccine inducing antibodies against human chorionic gonadotrophin (hCG). This vaccine consists of a heterospecies dimer (HSD, beta hCG associated with alpha-subunit of ovine luteinizing hormone, beta hCG:alpha oLH) linked to tetanus toxoid (TT) or diphtheria toxoid (DT) as carriers. The vaccine has recently passed an important milestone; it has completed the first leg of phase II efficacy trials. Women of proven fertility leading active sexual life were protected from becoming pregnant at antibody titres > or = 50 ng of hCG bioneutralization capacity per ml. This vaccine has previously been demonstrated to be reversible in its effect. It is free from any notable side-effects on endocrine, cardiovascular and other body functions. Ovulation was not disturbed and menstrual regularity was maintained. A logistic disadvantage of the present vaccine is the requirement for multiple injections. This is expected to be overcome by encapsulation of the requisite doses of the vaccine in biodegradable microspheres, which could be given at a single contact point for sustained antibody titres lasting over a year. A live recombinant vaccine has also been made that elicits high anti-hCG titres in monkeys for nearly 2 years following primary immunization and a booster at 8-9 months.

Contraception for the year 2020

Novel methods for the regulation of human fertility in the post-HIV era are discussed, based on the control of regulatory peptides and their respective genes. Three mechanisms are examined, each representing a step-wise increase in target or functional specificity. These centre on the selective control of the genes encoding the gonadotrophins and/or the interception of circulating gonadotrophins by receptor antagonists or binding proteins, the selective neutralisation of hCG and other signals involved in the maternal recognition of pregnancy by receptor antagonists and antibodies, and the interception of the putative disintegrin-integrin recognition events involved in sperm-oocyte recognition and fusion. A brief consideration is given to the use of vaccination procedures and somatic gene therapy for the long term regulation of fertility. By 2020, it is predicted that contraception, abortion and unplanned pregnancy could be replaced by reversible sterilisation based on the molecular interception of events involved in sperm-oocyte recognition and fusion. Contraceptive-like steroids will still be available but their use will be targeted to the provision of positive health care, with particular regard to breast cancer, osteoporosis and well-being.

Contraceptive vaccines

Three major approaches to contraceptive vaccine development are being pursued at the present time. The most advanced approach, which has already reached the stage of phase 2 clinical trials, involves the induction of immunity against human chorionic gonadotrophin (hCG). Vaccines are being engineered based on conjugates incorporating tetanus or diphtheria toxoid linked to a variety of hCG-based peptides centred on the beta-subunit of this molecule. Clinical trials have revealed that such preparations are capable of stimulating the production of anti-hCG antibodies. However, the long term consequences of such immunity in terms of safety or efficacy are, as yet, unknown. The alternative approaches to contraceptive vaccine development involve the induction of immunity against gamete-specific antigens found on the surface of the human spermatozoon or the zona pellucida. There is an abundance of experimental and clinical data to suggest that this approach is feasible although the biochemical characterization and synthesis of candidate antigens is still incomplete.

Anti-trophectoderm vaccines: rationale and methods used for antigen identification and selection

Trophoblast, forming a continuous interface at the maternal-fetal junction, is of considerable interest to biologists. An area of recent research is the search for trophoblast-specific antigens. It is believed that identification and characterization of these antigens may have many practical applications such as in development of contragestational vaccines. To be acceptable for humans such a vaccine will need to be effective before the completion of implantation and appearance of the primitive streak about 14 days after fertilization. This will not alter the menstrual cycle or the time of menses. Vaccines having a later effect resulting in termination of pregnancy after this time would be considered abortifacients. Although logistical and ethical considerations necessitated the use of post-implantation human trophoblast in WHO Birth Control Vaccine studies, the antigens isolated from such tissues would need to be expressed and be detectable on the surface of pre-implantation trophectoderm if they are to represent appropriate candidates for vaccine development. The criteria for identification and selection of these antigens will be reviewed.

Anti-LHRH and anti-pituitary gonadotropin vaccines: their development and clinical applications

Active immunization against hormones involved in the regulation of reproduction is a promising approach to immunocontraception. The hypothalamic peptide, LHRH, controls the synthesis and release of the pituitary gonadotropins, LH and FSH, which regulate gonadal steroidogenesis, sperm production, follicular development and ovulation. Immunizing female primates against LHRH or LH induces infertility, but also disrupts the menstrual cycle. Immunization against the beta subunit of the placental hormone, chorionic gonadotropin (hCG), or its fragment prevents pregnancy without interfering with menstrual cycles or ovulation. hCG vaccines have reached the stage of clinical trials. FSH and LHRH have been tested for immunocontraception in male primates. While active as well as passive immunization against FSH reduced spermatogenesis severely, azoospermia could not be achieved consistently. Immunization against LHRH effectively suppressed spermatogenesis in rats and rabbits. Normal sexual behaviour was maintained by concomitant androgen administration. Fertility was restored when antibody titres declined and no adverse effects were observed. A number of LHRH vaccine preparations are being tested in men in several countries, including the United States. Since the LHRH vaccine reduces serum testosterone levels the first clinical studies involve men with prostate cancer. These trials will be followed by immunization of normal men if the antibody response is sufficient and no adverse effects are observed.

Anti-hCG vaccines are in clinical trials

Two vaccines inducing antibodies against human chorionic gonadotropin (hCG) have completed Phase I clinical trials, indicating the reversibility and safety of these vaccines. One is currently in Phase II efficacy trials in women in three major centres in India. The available data suggest that the vaccine prevents pregnancy above antibody titres of 50 ng/ml hCG bioneutralization capacity.

Options for immunocontraception and issues to be addressed in the development of birth control vaccines

Although the number of family planning methods currently available to couples has never been greater, the range and type of options are still not adequate to meet the widely varying personal needs and demands of individuals worldwide. Birth control vaccines offer a number of theoretical attractions although the development, preclinical and clinical testing of such vaccines pose a number of unique problems requiring novel solutions. If the on-going studies in this area are successful, a valuable new family planning method may be available by the end of the current decade.

Contraception

The principle of vaccination for the purposes of fertility regulation is scientifically elegant and socially compelling. Factors such as economic production, convenience of use, relatively long-lasting but reversible protection, low failure rate and the avoidance of mechanical devices or exogenous hormones make this approach a potentially attractive option for family planning programmes in both developing and developed countries. The major efforts in research and development have involved the prospect of active immunization against specific antigens of sperm, oocyte, zygote and early embryo, and the pregnancy hormone human chorionic gonadotrophin (hCG). Several anti-hCG vaccines have entered clinical trials. They operate by preventing or interrupting pregnancy at the peri-implantation stage probably by neutralizing the luteotrophic effect of hCG. The most refined vaccine is one directed against the unique C-terminal peptide on the beta-subunit of hCG. This vaccine provokes antibodies that are specific for hCG and do not cross-react with human luteinizing hormone (hLH). Preclinical studies in baboons and data from a phase I human trial indicate that this method is free of side-effects and provides the promise of a duration of effectiveness of up to 12 months. Future research will optimize the anti-hCG approach, utilize new vaccine delivery systems and broaden the spectrum of target antigens of potential utility for contraceptive vaccines.

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.

Vaccines for control of fertility and hormone dependent cancers

Two vaccines, namely one inducing antibodies against hCG and the other against GnRH, are now in clinical trials. The hCG vaccine has entered Phase II clinical trials in three centres in India after successfully completing Phase I clinical studies in several centres in India and in four countries abroad. The vaccine was found to be devoid of side-effects; its effect was reversible. The available data on 179 cycles indicate that the vaccine prevents pregnancy at antibody titres above 50 ng/ml. A genetically engineered version of the vaccine has also been approved for trials in human lung cancer patients of the type which make hCG. hCG is observed to be a growth factor for such tumours. The GnRH vaccine is usable in both males and females as the deca-peptide is common to both sexes. Following suitable experimental and toxicology studies, the vaccine is currently in Phase I/Phase II clinical trials in patients of prostate carcinoma. Where antibody GnRH antibodies were induced, the LH, FSH and testosterone levels declined. This was accompanied by a reduction in prostate specific antigen. Clinical improvement was observed in many cases. The vaccine has also entered Phase I clinical studies in postpartum women, with the objective to extend the lactational amenorrhoea and extend inter-child interval.

Lactation, nutrition and fertility and the secretion of prolactin and gonadotrophins in Mopan Mayan women

The effect of lactation on menstrual cycles, ovulation and conception was studied in a group of non-contracepting Amerindian Mopan Mayan women. Anthropological observations of relevant events were made over a 21-month period. Blood samples were assayed to determine the plasma concentrations of prolactin, luteinising hormone, follicle stimulating hormone, human chorionic gonadotrophin, placental lactogen, oestrogen, progesterone and cortisol. The data show that: frequent and prolonged breast-feeding was associated with a marked increase in plasma prolactin concentrations to levels similar to those in lactating Gaing but higher than those in lactating Scottish women; ovulatory menstrual cycles and pregnancy occurred during frequent lactation; in lactating menstruating women there was an inverse correlation between fat weight and months post-partum. These data suggest that other factors as well as suckling account for the effects of lactation on fecundity.

Effect of predilatation of the uterine cervix by laminaria tent on activity of the placenta

Serum concentrations of hCG were determined in blood samples taken 18-20 h and immediately before vacuum aspiration in 45 women in gestational weeks 7-9, admitted for legal abortion. In 35 of the women, a laminaria tent was inserted for cervical dilatation immediately after the first blood sampling. Serum hCG values decreased significantly in the women pretreated with laminaria tent, but were unchanged in the untreated women. This finding may indicate that pretreatment with a laminaria tent induces a partial placental detachment.

Use of hCG stimulation test in women immunized with beta-hCG vaccine

Eleven normally menstruating women, who had earlier been immunized with NII beta-hCG vaccine but had no detectable anti-hCG antibody titres, were selected as controls for the hCG challenge test using 1000/2000 I.U. The test was repeated in five of them after a booster immunization, which raised antibody titres to 18-450 ng/ml. Stimulation of serum progesterone secretion was used as an index of corpus luteum (CL) response to the I.V. hCG. In the control group, the progesterone (P) secretory response following hCG stimulus showed peak levels which were significantly higher than basal levels in all except 2 subjects. The non-responsiveness in 2 subjects cannot be easily explained but may be dose-related. No significant difference was noted between the two dose levels. Length of luteal phase was increased by 4-5 days in 6 out of 20 cycles studied. The results of this test in 5 women before and after the vaccine boosters were encouraging as peak P levels appeared higher than basal levels in controls, but not so in the immunized group. However, these results could not be confirmed statistically. Nonetheless, this study is suggestive that the antibodies generated by this vaccine were capable of intercepting the effect of exogenous hCG in the human female. Further studies with more subjects and higher dosage of hCG are called for.

Suppression of corpus luteum function by the gonadotropin-releasing hormone antagonist Nal-Glu: effect of the dose and timing of human chorionic gonadotropin administration

OBJECTIVE

To assess the effect of gonadotropin-releasing hormone antagonist Nal-Glu administration in the luteal phase and the potential rescue by exogenous human chorionic gonadotropin (hCG) of corpus luteum (CL) after antagonist treatment.

DESIGN

We studied the dose of Nal-Glu required for luteolysis and subsequently we coadministered low doses of hCG for 3 consecutive days either simultaneously to Nal-Glu administration (n = 5), or 48 (n = 5), or 72 hours (n = 5) later. Six additional participants received pharmacological doses of hCG 48 hours after the luteolytic dose of Nal-Glu.

SETTING

Participants were studied in Clinique Endocrinologique, Nantes, and in Service d'Endocrinologie, Hôpital Bicêtre, Le Kremlin Bicetre, France.

PARTICIPANTS

Twenty-nine normal young women (ages 20 to 35) were studied.

INTERVENTIONS

None.

MAIN OUTCOME MEASURE

Measurements of follicle-stimulating hormone, luteinizing hormone (LH), estradiol, Progesterone (P) levels were performed by radioimmunoassay before, during, and after the various treatment regimens.

RESULTS

Complete luteolysis occurred in women who received 10 mg of Nal-Glu daily on days 4 and 5 after the LH surge. The coadministration of Nal-Glu and hCG overrode the effect of the antagonist (P = 48.8 +/- 22.5 versus 60.8 +/- 3.1 nmol/L in controls treated with hCG alone [NS]). When hCG treatment was started 48 hours after Nal-Glu, a partial luteolysis occurred (P = 33.8 +/- 10.9 versus 117 +/- 12.9 nmol/L, P less than 0.01). When hCG was started 72 hours after Nal-Glu, a complete luteolysis occurred (P = 5.8 +/- 2.05 versus 36.2 +/- 0.6 nmol/L, P less than 0.01). Higher doses of hCG (1,500 or 5,000 IU) administered 72 hours after Nal-Glu resulted in a significant rescue of CL function (P = 37.7 +/- 4.8 and P = 43.8 +/- 22.2 versus 74.5 +/- 19.8 and 130.2 +/- 14.3 nmol/L, P less than 0.05), respectively.

CONCLUSIONS

These results confirm the LH dependence of CL function. The suppression of CL LH support for 72 hours induced a compromise of the CL nonreversible by low doses of hCG mimicking early pregnancy but reversible with pharmacological doses.

Human chorionic gonadotrophin and alpha-fetoprotein levels in matched samples of amniotic fluid, extraembryonic coelomic fluid, and maternal serum in the first trimester of pregnancy

Separately identified samples of amniotic fluid and extraembryonic coelomic fluid obtained by high resolution transvaginal ultrasound-guided amniocentesis from 32 women between 7 and 12 weeks of pregnancy were analysed for human chorionic gonadotrophin (hCG) and alpha-fetoprotein (AFP). There was a highly significant difference between the hCG levels in amniotic fluid (median level 6.3 U/ml; range 1.6-310.0 U/ml) and those in extraembryonic coelomic fluid (median level 400.0 U/ml; range 135.0-2250.0 U/ml) (p less than 0.001; Mann-Whitney U-test). The levels of AFP were very similar in amniotic fluid (median 26.0 kU/ml; range 10.0-116.5 kU/ml) and extraembryonic coelomic fluid (median level 24.1 kU/ml; range 12.4-94.4 kU/ml).

The WHO Task Force on Vaccines for Fertility Regulation. Its formation, objectives and research activities

Over the past 18 years, the WHO Task Force on Vaccines for Fertility Regulation has been supporting basic and clinical research on the development of birth control vaccines directed against the gametes or the preimplantation embryo. These studies have involved the use of advanced procedures in peptide chemistry, hybridoma technology and molecular genetics as well as the evaluation of a number of novel approaches in general vaccinology. As a result of this international, collaborative effort, a prototype anti-HCG vaccine is now undergoing clinical testing, raising the prospect that a totally new family planning method may be available before the end of the current decade.

Pharmacokinetics of the antiprogesterone RU 486: no correlation to clinical performance of RU 486

The pharmacokinetics and metabolism of RU 486 were characterized in 17 women who received a single dose of 600 mg of RU 486 for termination of an early unwanted pregnancy. Based on the clinical outcome and serum chorionic gonadotropin values, the subjects were divided into two groups: those who aborted completely (i.e. responders: N = 13) and those who did not respond to RU 486 treatment (i.e. non-responders: N = 4). The serum levels of RU 486, the monodemethylated, didemethylated and hydroxylated metabolites of RU 486 were measured by HPLC preceded by column chromatography. There were no significant differences in the serum levels of RU 486 or its metabolites between the two groups. The serum concentrations of alpha 1-acid glycoprotein, the binding protein for RU 486, were quantitated by immunoturbidimetry. The alpha 1-acid glycoprotein concentrations were similar in responders and non-responders. The metabolism of RU 486 was also studied by fractionating extracts of serum pools of responders and non-responders on thin-layer chromatography, and subsequent RIA analysis of the eluates of the sliced thin-layer chromatography. Spots with similar distribution and percentages of cross-reactivity were found in both groups on the chromatography; the results were also similar to those from a serum pool to which synthetic RU 486 and its three metabolites had been added. Hence it is concluded that failure to abort in response to RU 486 therapy is not associated with altered pharmacokinetics or metabolism of RU 486.

Birth control vaccines and immunological approaches to the therapy of noninfectious diseases

Vaccination usually means the immunization of persons or animals against foreign infectious organisms for disease prevention. However, it has now been demonstrated that immunization against certain self substances to which tolerance normally exists can elicit beneficial effects to humans and other animals without inducing autoimmune disease. Clinical trials in women have been conducted with vaccines against reproductive antigens for the prevention of pregnancy and research is under way to develop more advanced formulations. Other self antigens have been described that might be used for developing methods of immunological therapy for such diseases as cancer, ulcers, and complications of diabetes. Emphasis is placed on the need for careful studies in appropriate animal models before any clinical application of such procedures is suggested.

Ovarian follicles during oral contraceptive cycles: their potential for ovulation

Ovarian follicles of a preovulatory size were encouraged to develop by extending the pill-free period of combine, triphasic oral contraceptive (OC) cycles. Despite recommencement of OC therapy, most follicles continued to grow and then respond to gonadotropin administration by both rupture and luteinization. It is concluded that follicles developing during OC cycles have the potential for ovulation, but this is of doubtful clinical significance for the vast majority of women.

Local methotrexate injection: a nonsurgical treatment of ectopic pregnancy

Twenty seven patients with unruptured tubal pregnancy were selected for nonsurgical treatment with the use of one injection of 12.5 mg of methotrexate into the ectopic site at laparoscopy. No adverse reactions were observed. In three patients (11%), a laparotomy was performed because of rising beta-human chorionic gonadotropin titers. In the other patients, serum beta-human chorionic gonadotropin levels decreased to the nonpregnant range with no further intervention, and the patients recovered uneventfully. This method is suggested as an alternative to surgery in selected cases of early unruptured tubal pregnancy.

Variable effects of RU 486 on endometrial maintenance in the luteal phase extended by exogenous hCG

This study was designed to assess the features and conditions for endometrial bleeding induction with the synthetic antiprogestin and antiglucocorticoid RU 486 during hCG-induced prolongation of the luteal phase. Eighteen healthy, surgically sterilized women and another five women with an intrauterine contraceptive device (IUD) participated. All subjects received hCG which was injected daily in increasing doses (500 to 15,000 IU) from day 9 to day 15 of the luteal phase. Ten subjects received hCG alone, and groups of three to 16 subjects received hCG combined with RU 486 (25, 50, 100, 200 or 400 mg/day). RU 486 administration was commenced on day 12 following the LH surge and given either for 1, 4 or 7 consecutive days. In certain cycles, tamoxifen (20 mg/day) was given for 4 consecutive days with hCG, or with hCG and RU 486. All treatment cycles were separated by one or two resting cycles. Frequent blood samples were taken to monitor the endocrine response. Treatment with hCG alone or with the various combinations of RU 486 produced similar serum levels of oestradiol and progesterone which were equivalent to those observed during early pregnancy. With hCG alone, the onset of bleeding was on day 21-24 after the LH surge, coinciding with the drop in oestradiol and progesterone. With RU 486 doses of 50 mg/day or more, an early bleeding episode almost invariably occurred on day 14-17 after the LH surge in the presence of high circulating steroid levels. In contrast, 25 mg/day RU 486 for 4 days failed to induce this early onset of bleeding in three out of six cases.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of steroids on the fine structure of the endometrium

This brief review illustrates the lack of ultrastructural studies on human endometrium, particularly on well-dated material from normal, fertile women. The glandular epithelium, with its triad of unusual organelles in the early luteal phase, poses fascinating problems in cell biology and, probably for this reason, has attracted the most work. Many problems in reproductive biology, in uterine pathology and in the study of unexplained infertility are crying out for detailed study of the luminal epithelium, the stroma and the blood vessels. If this review, by highlighting the gaps in our knowledge, stimulates research into these areas, it will have been successful.

Anti-fertility vaccines

Vaccines are under development for the control of fertility in males and females. This review discusses developments in anti-fertility vaccines at the National Institute of Immunology, New Delhi, India. A single injection procedure for the sterilization or castration of male animals depending on the site at which the injection is given, has passed through field testing and is expected to be on the market in the near future. Vaccines inducing antibodies against the human chorionic gonadotropin have gone through phase I trials with satisfactory results. A vaccine producing a consistently bioeffective antibody response against gonadotropin-releasing hormone is ready for phase I/II clinical trials in patients of carcinoma of prostate after due experimentation in animals and toxicology studies. Research to identify sperm antigens for incorporation into second generation vaccines is in progress.