Effects of LH suppression in polycystic ovary syndrome

WITHDRAWN: Gonadotrophin therapy for ovulation induction in subfertility associated with polycystic ovary syndrome

This review has been replaced by a review entitled 'Gonadotrophins for ovulation induction in women with polycystic ovarian syndrome'.

The editorial group responsible for this previously published document have withdrawn it from publication.

Gonadotrophin therapy for ovulation induction in subfertility associated with polycystic ovary syndrome

BACKGROUND

Approximately 15% of patients with PCOS remain anovulatory despite treatment with oral anti-oestrogen medications such as clomiphene citrate. In addition, about half of women with PCOS ovulating on anti-oestrogen treatment fail to conceive. Gonadotrophin stimulation is the next step in treatment for women who are "clomiphene resistant", however, results of gonadotrophin stimulation in women with PCOS are less successful. In PCOS associated with hypersecretion of LH, purified urinary follicle-stimulating hormone (u-FSH) preparations have theoretical advantages over the use of human menopausal gonadotrophin (hMG) preparations (containing both FSH and LH), but whether this claimed advantage extends into clinical practice remains uncertain. In addition, the use of gonadotrophin-releasing hormone analogues (GnRH-a) to produce pituitary desensitisation prior to ovulation induction in PCOS has been claimed to increase the success rates of treatment as well as reduce complications such as OHSS and multiple pregnancy. Gonadotrophin preparations have also been administered via different routes (intramuscular or subcutaneous), or using different stimulation regimens and protocols (step-up or standard) in an attempt to improve efficacy.

OBJECTIVES

To determine the effectiveness of urinary-derived gonadotrophins as ovulation induction agents in patients with PCOS trying to conceive. In particular, to assess the effectiveness of (1) different gonadotrophin preparations, (2) the addition of a gonadotrophin-releasing hormone agonist (GnRH-a) to gonadotrophin stimulation and (3) different modalities of gonadotrophin administration.

SEARCH STRATEGY

The search strategy to identify RCTs consisted of (1) the Group's Specialised Register of Controlled Trials using the search strategy developed for the Menstrual Disorders and Subfertility Group as a whole (see the Review Group details for more information), (2) additional specific electronic Medline searches and (3) bibliographies of identified studies and narrative reviews.

SELECTION CRITERIA

RCTs in which urinary-derived gonadotrophins were used for ovulation induction in patients with primary or secondary subfertility attributable to PCOS.

DATA COLLECTION AND ANALYSIS

Twenty three RCTs were identified, 9 of which were excluded from analysis. The data were extracted independently by 2 authors. The following criteria were assessed: (1) the methodological characteristics of the trials, (2) the baseline characteristics of the studied groups and (3) the outcomes of interest: pregnancy rate (per cycle), ovulation rate (per cycle), miscarriage rate (per pregnancy), multiple pregnancy rate (per pregnancy), overstimulation rate (per cycle) and ovarian hyperstimulation syndrome (OHSS) rate (per cycle). Where suitable, meta-analysis was performed using Peto's OR with 95% CI with the fixed effect Mantel-Haentszel equation.

MAIN RESULTS

(1) A reduction in the incidence of OHSS with FSH compared to hMG in stimulation cycles without the concomitant use of a GnRH-a (OR 0.20; 95% CI 0.08-0.46) and (2) a higher overstimulation rate when a GnRH-a is added to gonadotrophins (OR 3.15; 95% CI 1.48-6.70).

REVIEWER'S CONCLUSIONS

Although 14 RCTs were included in this review, few dealt with the same comparisons, all were small to moderate size and their methodological quality was generally poor. Any conclusions, therefore, remain tentative as they are based on a limited amount of data and will require further RCTs to substantiate them. In none of the comparisons was there a significant improvement in pregnancy rate but this may be due to the lack of power (i.e. insufficient patients randomised to demonstrate a significant difference between treatments). There was a trend towards better pregnancy rates with the addition of a GnRH-a to gonadotrophin stimulation and these interventions warrant further study. Despite theoretical advantages, urinary-derived FSH preparations did not improve pregnancy rates when compared to traditional and cheaper hMG preparations; their only demonstrable benefit was a reduced risk of OHSS in cycles when administered without the concomitant use of a GnRH-a. No conclusions can be drawn on miscarriage and multiple pregnancy rates due to insufficient reporting of these outcomes in the trials.

Combined GnRH-agonist and HMG therapy in patients with stimulation failure

This study deals with the combined therapy of GnRH-agonist (GnRH-a) and HMG for stimulation in 15 patients who failed two prior in vitro fertilization attempts. Fifty-three patients who received HMG without GnRH-agonist suppression served as controls. Comparing the HMG group with GnRH-a/HMG cycles, the cancellation rate dropped from 35.5% to 13.2%. Oocyte recovery was similar in both groups, as were the fertilization rates, 88.4% in GnRH-a and 82% in HMG cycles, respectively. The number of embryos available for transfer was virtually identical in both groups (3.7 vs. 3.6). Embryo cleavage speed was higher in GnRH-a than in HMG regimens. The E2 rise was smooth in the GnRH-a group compared to the sharp rise observed in the HMG group. The pregnancy rate per transfer was 30.5% in the GnRH-a group versus 20.5% in the HMG group. GnRH-a seems to offer a clear improvement to a number of stimulation failures.

Complete ovarian unresponsiveness to hMG stimulation after prolonged GnRH analogue administration

GnRH agonists (GnRH-a) have recently been shown to exert an inhibitory effect on human reproductive functions, the mechanism for this effect being attributed solely to the desensitization of the pituitary gonadotropin receptors to GnRH-a. We present two cases where chronic treatment with a GnRH-a caused complete suppression of ovarian activity in vivo. The effect could not be counteracted by large hMG doses and resulted in high FSH plasma concentrations. Normal ovarian activity was restored only after withdrawal of GnRH-a.

The comparison of early follicular and midluteal administration of long-acting gonadotropin-releasing hormone agonist

Long-acting GnRH-a (D-Trp6 microcapsules, 3.2 mg) was intramuscularly injected, either in early follicular phase (group A) or midluteal phase (group B). Two hundred sixteen cycles were randomly allocated. Ovarian suppression was significantly more prompt in group B. Follicle cysts were diagnosed in 19% and 16% of groups A and B, respectively; their appearance and regression were significantly more rapid in group B cycles. More ampules of human menopausal gonadotropin were needed in group B. The number of oocytes retrieved was not significantly different between the groups. However, in group A more mature oocytes and more embryos with good morphology were achieved in the patients. Cancellation rate was 2.8% in groups A and B. Pregnancy rate and outcome were similar in both groups.

Buserelin. A review of its pharmacodynamic and pharmacokinetic properties, and clinical profile

The gonadotrophin releasing hormone (GnRH) [luteinising hormone-releasing hormone (LHRH); gonadorelin] agonist buserelin is a promising new agent in the treatment of a variety of disorders in gynaecology and andrology, paediatrics and oncology. While a single dose of buserelin stimulates the release of pituitary gonadotrophins, multiple doses produce reversible pituitary desensitisation, and this specific blockade of gonadotrophin support to the gonads provides the basis for the drug's efficacy in conditions dependent on sex hormone secretion. Thus, buserelin provides comparable efficacy to orchidectomy or high dose estrogens in the treatment of hormone-sensitive prostate cancer and exhibits a lower incidence of adverse effects. During the early phase of treatment it may be particularly useful in combination with antiandrogens. Buserelin also appears promising in hormone-sensitive premenopausal breast cancer. Extensive studies have proven the value of buserelin in endometriosis, where it produces a transient remission with gradual recurrence of the disease on cessation of treatment. Surgical intervention is necessary in severe disease after buserelin-induced involution of the lesions. In patients with uterine leiomyoma, preliminary data suggest that buserelin may be beneficial in rendering surgery more conservative by reducing fibroid size, although it appears unlikely to preclude surgical intervention. The use of buserelin to induce a state of reversible hypogonadotrophism before administration of exogenous gonadotrophins is a promising strategy in the treatment of infertility associated with polycystic ovary syndrome and other conditions of infertility with underlying ovarian dysfunction; such a strategy also clearly enhances the efficiency of in vitro fertilisation programmes. Initial studies suggest its potential usefulness as a female contraceptive when administered intermittently in conjunction with a progestogen. Buserelin represents a first-line treatment of central precocious puberty. In endometriosis the adverse effect profile of buserelin is generally favourable, with hypoestrogenic effects such as hot flushes and vaginal dryness, and decreased libido, predominating. There is no apparent detrimental effect on lipid metabolism. The potential for adverse hypoestrogenic effects on bone mineral content with long term administration remains to be clarified. Thus, the GnRH agonist buserelin represents an advance in the treatment of a variety of gynaecological and andrological as well as paediatric and oncological conditions, infertility and other sex-hormone dependent conditions, with a low incidence of adverse treatment effects.

Ovarian sensitivity to gonadotrophins in patients with PCO is unaffected by suppression of LH

Infertile women with oligomenorrhoea and elevated LH concentrations (presumed polycystic ovary disease, PCO) were treated with exogenous gonadotrophins, HMG and HCG, for induction of follicular growth and ovulation, respectively. This was effected in the absence or presence of a gonadotrophin releasing hormone analogue (GnRH-A) to suppress basal LH and the positive feedback surge of LH. Analyses of the duration of HMG therapy required to attain the degree of stimulation for HCG to be administered showed no difference between those with and without LH suppression. Analyses of the ultrasound estimations of rates of follicle growth and continued recruitment during the course of HMG also failed to show any effect of LH suppression. These data show that the high sensitivity of these patients to HMG is not related to the circulating LH concentrations.

[Treatment of ovarian polycystic syndrome in vitro. Physiopathogenetic considerations]

More than 60% of patients with polycystic ovary disease (PCO) cannot conceive after repeated ovulation inductions with Clomifene citrate although there is ovulation or more frequently follicle luteinization. Because of hyperstimulation, therapy with hMG has been superseded by low doses of purified FSH with variable results according to authors. It has been even claimed that there was no benefit to replace hMG with FSH. However, on the basis of the PCO physico-pathology, namely LH hypersecretion and androgen hyperproduction, it would be rational to associate the desensitization of the pituitary with LH-RH agonist and the ovary stimulation with variable doses of hMG or purified FSH. In the series where such therapy associating LH-RH agonists with purified FSH was applied, the results concerning suppression of LH and androgen secretion, and the occurrence of pregnancy were interesting. However, the risk of hyperstimulation still occurred. Thus, the first part concerns the critical review of these results while, in the second part, our experience in in vitro fecundation will be reported.

Value of suppression with a gonadotropin-releasing hormone agonist prior to gonadotropin stimulation for in vitro fertilization

This study examined the use of gonadotropin-releasing hormone agonist (GnRHa) suppression before gonadotropin stimulation in 26 patients with failed prior in vitro fertilization (IVF) attempts and variable basal serum gonadotropin levels. Leuprolide, 1 mg subcutaneously per day, was administered from the midluteal phase of the cycle before IVF treatment. Concomitantly, stimulation was initiated on cycle day 3 with human menopausal gonadotropin (hMG) and follicle stimulating hormone (FSH). Based on their prior IVF attempts and serum gonadotropin levels on cycle day 3, 9 patients were high responders with elevated mean basal luteinizing hormone (LH)/FSH, 8 were low responders with elevated mean basal FSH/LH, 7 were intermediate responders with normal mean basal FSH/LH and a history of premature LH surge, and 2 had elevated (perimenopausal) mean FSH and LH. Leuprolide was discontinued on the day of human chorionic gonadotropin (hCG) administration. Prior IVF attempts in the same patients with the same protocol, but without GnRHa suppression, were used as controls. The mean number of ampules of hMG and FSH was significantly higher in leuprolide cycles than in controls. The mean day of hCG administration was also higher for leuprolide cycles than for controls. The mean LH and progesterone levels on the day of hCG were significantly lower in leuprolide cycles. The mean number of preovulatory oocytes aspirated and transferred was higher in leuprolide cycles. Cancellation and pregnancy rates were improved in leuprolide cycles. It is concluded that prior GnRHa suppression is beneficial for follicular recruitment for IVF. More patients with variable basal serum gonadotropin levels need to be studied before definite recommendations are made.

Treatment of polycystic ovarian disease by inducing ovulation with pulsatile subcutaneous administration of human menopausal gonadotrophin associated with luteinizing hormone-releasing hormone analogue

Treatment with a combination of luteinizing hormone-releasing analogue (GnRHa, Buserelin) and pulsatile administration of hMG (Group I) were used to induce ovulation in nine patients with polycystic ovary syndrome (PCO). The same patients were also treated with pulsatile hMG administration alone (Group II). Ovulation was observed in all twelve treatment cycles in Group I, and there were two pregnancies. In Group II, ovulation occurred in 22 of 26 treatment cycles. Ovarian hyperstimulation occurred in one cycle of Group I and in 5 of 26 cycles of Group II. The total dose per cycle of hMG to induce ovulation in Group I was significantly lower than that needed when only pulsatile hMG administration was used. In response to Buserelin administration, the concentrations of serum luteinizing hormone (LH) and follicle stimulating hormone (FSH) increased transiently and then declined to the normal range observed in the early follicular phase. The concentrations of FSH increased in response to hMG administration, resulting in a normal LH/FSH ratio. The present data demonstrated that pulsatile subcutaneous administration of hMG in addition to Buserelin was effective in inducing follicular maturation and ovulation in patients with PCO with a lower incidence of serious side-effects.

LHRH analogues for ovulation induction, with particular reference to polycystic ovary syndrome

Infertile women with PCO have been treated with exogenous gonadotrophins (hMG/hCG) for ovulation induction either with or without LHRH-agonist treatment. Those treated without LHRH-agonist-induced LH suppression showed PL in greater than 30% of the cycles and this problem was eliminated by LHRH-agonist therapy. The pregnancy rate (approximately 80% of patients) during the combined therapy was approximately twice that of the group treated with hMG/hCG alone. The suppression of endogenous LH by the LHRH-agonist appeared to have no effect upon the profiles of follicular development in response to hMG, and a high rate of follicle recruitment characterized all PCO treatment cycles irrespective of circulating LH concentrations. These results suggest that LH suppression improves the efficacy of ovulation induction but has no influence on the primary metabolic disturbance in the PCO syndrome.

Combined gonadotropin-releasing hormone analog and exogenous gonadotropins for ovulation induction in infertile women: efficacy related to ovarian function assessment

The ovarian function of infertile women with normal menstrual rhythm was investigated by daily plasma hormone (estradiol, progesterone, luteinizing hormone, and follicle-stimulating hormone) analyses throughout the menstrual cycle, and patients were diagnosed as showing a subnormal profile of progesterone in the early luteal phase or as showing no abnormality. Women with oligomenorrhea and elevated luteinizing hormone levels were diagnosed as having polycystic ovary syndrome primarily on the basis of endocrinology. All patients were treated with a gonadotropin-releasing hormone analog to suppress endogenous luteinizing hormone and follicle-stimulating hormone so that ovulation induction with exogenous gonadotropins could be undertaken as in patients with hypogonadotropic hypogonadism. Interference in the process of ovulation by endogenous luteinizing hormone fluctuations was eliminated and pregnancies were achieved. The pregnancy rate in the group with polycystic ovary syndrome was 77% per treatment course (six cycles) while that in the group with subnormal progesterone profiles was 61.5%. Patients showing no abnormality achieved no pregnancy, demonstrating the redundancy of interference with normal ovarian function.

Successful use of gonadotropin-releasing hormone agonist leuprolide for in vitro fertilization in a patient with polycystic ovarian disease and infertility unresponsive to standard treatment

A patient with PCO and primary infertility had undergone numerous failed attempts of ovulation induction. She then was treated with GnRHa leuprolide 500 micrograms subcutaneously daily for 4 weeks, later combined with hMG 225 IU IM daily for 8 days and hCG 5000 IU IM. Six oocytes were retrieved for IVF, four fertilized and two were replaced. Twin pregnancy was established and delivered at term. Hyperstimulation syndrome was managed conservatively.

An alternate approach to controlled ovarian hyperstimulation in "poor responders": pretreatment with a gonadotropin-releasing hormone analog

Pharmacologic hypophysectomy was induced with a subcutaneous injection of leuprolide acetate before the administration of exogenous gonadotropins for multiple follicle development in 27 women who had previously responded poorly to conventional controlled ovarian hyperstimulation (COH). Pituitary desensitization occurred within 6 days and concurrent COH with exogenous gonadotropins resulted in an enhanced yield of oocytes in comparison to previous COH attempts (P less than 0.05). Fertilization and pregnancy rates also were higher with gonadotropin-releasing hormone agonist (GnRHa) treatment (P less than 0.01). The administration of leuprolide acetate effectively suppressed endogenous gonadotropin secretion when initiated in the follicular or luteal phase of the menstrual cycle. GnRHa therapy can appreciably facilitate the management of gonadotropin therapy, and increase the probability of oocyte collection and pregnancy.

The effect of oral contraceptives on hormone profiles of oligomenorrheic adolescent cycles

Nineteen adolescent girls with oligomenorrhea were studied to evaluate the effect of oral contraceptives (OCs) on hormone profiles, and 19 adolescent girls with regular menstruations served as control subjects. Serum levels of luteinizing hormone and androgens were higher in the oligomenorrheic girls than in the regularly menstruating girls. During the OC treatment the hormone levels of the oligomenorrheic girls decreased, approaching those of the control subjects. During follow-up cycle immediately after stopping the OCs the hormone levels increased rapidly, but in the oligomenorrheic girls the levels of luteinizing hormone, androstenedione, total and free testosterone were still significantly lower at the end of the post-treatment cycle than during the luteal phase of the pre-treatment cycle. The frequency of ovulation decreased to the same magnitude as reported in adults after discontinuation of OCs. No post-pill amenorrhea existed in either group of adolescents.