Pituitary gonadotrophin secretory capacity during the luteal phase in superovulation using GnRH-agonists and HMG in a desensitization or flare-up protocol.

Pituitary gonadotrophin reserve and basal gonadotrophin secretion were tested during the luteal phase in women superovulated with buserelin/human menopausal gonadotrophin (HMG) in a desensitization (n = 17) or flare-up protocol (n = 7). In the desensitization protocol the luteinizing hormone-releasing hormone (LHRH) stimulated serum LH and follicle stimulating hormone (FSH) concentrations remained impaired at least until day 14 after arrest of the agonist. In the flare-up protocol basal and stimulated LH secretion was still abnormal on days 14 and 15 after human chorionic gonadotrophin (HCG) injection. Normal basal serum FSH concentrations were measured at the end of the luteal phase in the flare-up protocol, but the response of FSH to LHRH injection was still subnormal. We conclude that gonadotrophin function remained impaired until the end of the luteal phase after desensitization and flare-up GnRH-agonist and HMG stimulation protocols. Corpus luteum stimulation with exogenous HCG or substitution therapy using natural progesterone are required to prevent the possible negative effects resulting from pituitary dysfunction after GnRH-agonist treatment.     

Analysis of hormonal changes during combined buserelin/HMG treatment

Changes of serum oestradiol, LH and progesterone have been analysed in view of the effect of the GnRH analogue buserelin on the late follicular and early luteal phase of cycles stimulated with combined buserelin/HMG (n = 31) in an IVF-ET/GIFT programme. Patients undergoing cycles with HMG only (n = 57) served as the control group. With the use of the GnRH analogue buserelin, a significantly higher amount of HMG (25 versus 20 ampoules; P less than 0.001) for a significantly longer stimulation period (10 versus 8 days; P less than 0.001) was necessary to achieve the same oestradiol response as seen in HMG cycles. Serum progesterone levels during a three day period before ovulation induction tended to be lower in the combined buserelin/HMG cycles than in cycles with HMG stimulation only. We did not observe any significant difference in the luteal phase progesterone levels of the buserelin/HMG and the HMG group. On the other hand, we found that an inadequate luteal phase in buserelin/HMG cycles could be avoided by HCG administration during the luteal phase. Both the elevation of basal serum LH and a premature LH rise could also be avoided by the use of buserelin.     

Follicular and luteal phase characteristics following early cessation of gonadotrophin-releasing hormone agonist during ovarian stimulation for in-vitro fertilization

Gonadotrophin-releasing hormone agonists (GnRHa) are widely used in in-vitro fertilization (IVF) for the prevention of a premature rise in luteinizing hormone (LH) concentrations. However, the administration of GnRHa during the follicular phase may also impair subsequent luteal function due to retarded recovery of pituitary gonadotrophin secretion. Therefore, luteal supplementation is generally applied. The present study was designed to determine whether a premature LH surge would still be prevented after early cessation of GnRHa during ovarian stimulation and whether subsequent luteal phase LH production would be sufficient to support progesterone synthesis by the corpus luteum. Sixty patients were randomized for three groups: (i) A long GnRHa/human menopausal gonadotrophin (HMG) protocol with luteal support by repeated human chorionic gonadotrophin (HCG) (n = 20), (ii) early follicular phase cessation of GnRHa without luteal support (n = 20), and (iii) a long GnRHa protocol without luteal support (n = 20). Frequent ultrasound and blood sampling was performed during the entire IVF cycle. Forty normo-ovulatory women served as controls. No premature LH surges were found after early cessation of GnRHa. In this group, some pituitary recovery occurred during the late luteal phase, but this did not affect corpus luteum function. Progesterone concentrations were shown to be dependent on disappearance of the pre-ovulatory bolus of HCG. Pregnancies occurred in all three groups. In conclusion, early follicular phase cessation of GnRHa is still effective in the prevention of a premature rise in LH. Although some pituitary recovery was observed thereafter, corpus luteum function is still abnormal due to early luteolysis.     

Differential effect of exogenous human chorionic gonadotrophin on progesterone production from normal or malfunctioning corpus luteum

To examine whether luteal phase defect is, in part, causally related to insufficient gonadotrophin stimulation, we compared the relation of the increment of serum progesterone concentrations in response to human chorionic gonadotrophin (HCG) with its basal level at mid-luteal phase. Thirty-eight naturally cycling infertile women aged between 27-41 years old were evaluated for hormonal responses to HCG injection at the mid- luteal phase. We measured luteinizing hormone (LH), follicle stimulating hormone (FSH), oestradiol and progesterone concentrations, before and 1, 2 and 3 h after the administration of HCG (5000 IU, i.m.) 7 days after ovulation verified by ultrasonography. Eleven out of 38 women exhibited progesterone concentrations below 10 ng/ml (low progesterone group), and those remaining showed progesterone concentrations of > or = 10 ng/ml (normal progesterone group). The basal LH, FSH and oestradiol concentrations were essentially the same in both groups. Progesterone concentrations rose significantly 1 h after the injection and levelled off thereafter. The increment of progesterone concentrations at 1 h in the normal progesterone group was 5.7 ng/ml on the average, whereas that in low progesterone group was 1.1 ng/ml. Furthermore, the percentage increase in progesterone concentrations at 1 h in the normal progesterone group was significantly greater than that in the low progesterone group. Both groups equally exhibited significant but marginal increases in oestradiol concentrations 1 h after the injection. LH and FSH concentrations at 3 h decreased significantly in both groups. In summary, HCG readily stimulates progesterone production in normally functioning corpus luteum whereas its stimulatory effect is minimal on malfunctioning corpus luteum. This suggests that luteal phase defect is not caused by inadequate gonadotrophin stimulation and, therefore, does not benefit from HCG administration.      

Pregnancy: Serum placental protein 14 concentrations are similar in the first trimester pregnancies of women after pituitary down-regulation with a gonadotrophin-releasing hormone agonist and normal cycles with frozen embryo transfers

Previous studies suggest that, in pregnancies after in-vitrofertilization (IVF) and embryo transfer following pituitarydown-regulation with a gonadotrophin-releasing hormone analogue(buserelin) and ovulation induction with human gonadotrophins,the serum placental protein 14 (PP14) concentration is lowerthan in normally conceived pregnancies. We studied serum PP14concentrations in two groups of women: (i) in 17 infertile womenwhose pregnancy followed IVF and embryo transfer using buserelin(long protocol) and human menopausal gonadotrophin for ovulationinduction; (ii) in 15 women whose pregnancy followed transferof frozen-thawed embryos. Similar PP14 concentrations were foundin both groups on days 9–10, 14–15 and 70–77after human chorionic gonadotrophin administration (buserelin,IVF/embryo transfer) or spontaneous luteinizing hormone surge(frozen-thawed embryo transfer). Our results show that PP14secretion is not compromised by pituitary down-regulation withbuserelin in infertile women with functional ovaries.     

Peritoneal fluid volume and levels of steroid hormones and gonadotrophins in peritoneal fluid of normal and norethisterone-treated women.

Peritoneal fluid and blood samples were collected at surgical sterilization from 30 untreated women at various stages of the luteal phase and from 43 women treated with 300 micrograms norethisterone daily. Levels of oestradiol, progesterone, luteinizing hormone (LH) and follicle stimulating hormone (FSH) were measured. The highest peritoneal fluid volume (mean, 23.1 ml) was found in the early luteal phase (LH 0 to + 3) and the lowest (mean, 5.9 ml) in the late luteal phase (LH + 12 to menses). The norethisterone treatment diminished the formation of peritoneal fluid and the degree of inhibition was dependent upon the type of ovarian reaction to norethisterone. Progesterone and oestradiol levels were higher in peritoneal fluid compared to plasma throughout the luteal phase and during norethisterone treatment. A comparison of the levels of these steroids between untreated controls (LH + 8 to + 11) and norethisterone-treated women demonstrated that the progesterone levels in peritoneal fluid were highly reduced by norethisterone treatment, while the oestradiol levels were not affected. The FSH and LH levels were, in contrast to the steroid hormones, significantly lower in peritoneal fluid than in plasma, both in the untreated and the treated women. No differences in the FSH or LH levels between the untreated and treated women were found. The results indicate that the peritoneal fluid volume and the steroid hormone levels in peritoneal fluid vary with the stages of the luteal phase. Norethisterone treatment significantly reduced the peritoneal fluid volume as well as its progesterone concentration, whereas the oestradiol and gonadotrophin levels remained unchanged.     

Is there a difference in the function of granulosa-luteal cells in patients undergoing in-vitro fertilization either with gonadotrophin-releasing hormone agonist or gonadotrophin-releasing hormone antagonist?

Gonadotrophin-releasing hormone (GnRH) regulates gonadotrophin release. It has been shown that GnRH may have a direct effect on the ovary, as the addition of GnRH to granulosa cell cultures inhibits the production of progesterone and oestradiol. Specific GnRH receptors have been found to be present in rat and human granulosa cells. Desensitization of the pituitary by GnRH agonist has become common in in-vitro fertilization (IVF) treatment, usually by a long protocol of 2-3 weeks. With the introduction of GnRH antagonists, which produce an immediate blockage of the GnRH receptors, a much shorter exposure is needed of 3-6 days. The aim of this study was to evaluate the effect of a GnRH agonist (buserelin) and a GnRH antagonist (cetrorelix) on the function of granulosa cells cultured in vitro from IVF patients. Women were treated by IVF randomized either to have buserelin nasal spray from the luteal phase in the previous cycle or cetrorelix from day 6 of the cycle. Both groups had ovarian stimulation with human menopausal gonadotrophin (HMG) 150 IU daily, i.e. HCG was administered when the follicles were larger than 17 mm, and aspirated 36 h later. Granulosa cells, separated and washed from large follicles containing ova, were pooled. After 48 h of pre-incubation, the granulosa cells were cultured for 4 days in medium with either added testosterone or cAMP with or without HCG, with change of medium after 2 days. The progesterone and oestradiol concentrations in the culture medium were measured by immunological assay, and cellular protein was measured by microprotein assay. The results showed that granulosa cells from women treated with GnRH antagonist (cetrorelix) responded earlier to the in-vitro hormone stimulation in terms of progesterone accumulation than women treated with the GnRH agonist (buserelin). This may have been due to difference in time of exposure to the analogue. The results may indicate that the luteal function is less impaired in GnRH antagonist treatment than in GnRH agonist treatment.     

Ovarian stimulation with HMG: results of a prospective randomized phase III European study comparing the luteinizing hormone-releasing hormone (LHRH)-antagonist cetrorelix and the LHRH-agonist buserelin. European Cetrorelix Study Group

In this prospective and randomized study, 188 patients received the luteinizing hormone-releasing hormone (LHRH) antagonist cetrorelix, and 85 patients the LHRH agonist buserelin to prevent endogenous luteinizing hormone (LH) surges during ovarian stimulation in in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles. Ultimately, 181 patients (96.3%) in the cetrorelix group, and 77 (90.6%) in the buserelin group, reached the day of the human chorionic gonadotrophin (HCG) injection. The mean number of human menopausal gonadotrophin (HMG) ampoules administered and the mean number of stimulation days with HMG were significantly less in the cetrorelix group than in the buserelin group (P < 0.01). A rise in LH and progesterone concentrations was observed in three of the 188 patients (1.6%) who received cetrorelix. On the day of the HCG administration, more follicles of a small diameter (11-14 mm) were observed in the buserelin group than in the cetrorelix group (P = 0. 02) and the mean serum oestradiol concentration was significantly higher in patients who received buserelin than in those who received cetrorelix (P < 0.01). Similar results were observed in fertilization, cleavage and pregnancy rates in the two groups. In conclusion, the use of the LHRH antagonists might be considered more advantageous because of the short-term application needed to inhibit gonadotrophin secretion, so allowing a reduction in the treatment time in a clinically significant manner.     

Luteal phase support and severe ovarian hyperstimulation syndrome.

The incidence and statistical associations of the ovarian hyperstimulation syndrome (OHSS) were studied in 304 egg retrievals with gonadotrophin-releasing hormone agonist suppression, gonadotrophin administration and follicular aspiration. In addition to preserving corpus luteum function, the luteal phase administration of human chorionic gonadotrophin (HCG) was associated with a higher incidence of severe OHSS than was supplementation with progesterone alone (12 versus 0%, P less than 0.001). Severe OHSS occurred in 3.7% and 12% of retrievals without and with pregnancy respectively (P less than 0.01). Stepwise logistic regression showed that the occurrence of moderate or severe OHSS was statistically predicted by the log of the serum oestradiol on the day the initial HCG was given (P less than 0.0001), treatment with luteal phase HCG (P less than 0.0003), and fetal number (P less than 0.0079). In the late luteal phase of cycles without luteal HCG, the serum oestradiol concentration was one-tenth and the serum progesterone concentration was one-fifth of the luteal phase value with HCG support (P less than 0.001). Without luteal phase HCG, oestradiol was two-fold higher (P less than 0.001) and progesterone was 1.4-fold higher (P less than 0.005) in pregnant than in non-pregnant women. With luteal phase HCG, oestradiol was 1.4-fold higher in pregnant than in non-pregnant women (P less than 0.05), and progesterone was 1.7-fold higher (P less than 0.001). Oestradiol upper limits of 4400 and 14,700 pmol/l (1200 and 4000 pg/ml) for cycles with and without luteal phase HCG respectively correspond to approximately 5% risk of moderate or severe OHSS with a singleton pregnancy under these conditions.     

Is continuation of a gonadotrophin-releasing hormone agonist (GnRHa) necessary for women at risk of developing the ovarian hyperstimulation syndrome?

A total of 28 women scheduled for in-vitro fertilization used buserelin and human menopausal gonadotrophin (HMG) for ovarian stimulation. One group (I) of 17 women was given human chorionic gonadotrophin (HCG 10,000 IU) to trigger ovulation, but the resulting embryos were electively cryopreserved because of the risk (serum oestradiol greater than or equal to 3500 pg/ml) of developing the ovarian hyperstimulation syndrome (OHSS). Six women continued the buserelin therapy in the luteal phase and eleven did not. In group II (n = 11), the HMG injections were discontinued because of an exaggerated ovarian response and the HCG was omitted. Six of these women continued the buserelin injections until the onset of menses and five did not. In both groups, the ovarian response to induction of ovulation (serum oestradiol concentrations and number of follicles) was similar for those who did or did not continue buserelin therapy. There was no difference in the rate of ovarian quiescence (weekly fall in serum oestradiol concentration following the stimulation) between those women who did or did not continue the buserelin therapy in either group. The serum luteinizing hormone concentrations remained low in all women in both groups. We conclude that the omission of buserelin therapy after discontinuing the HMG in women at risk of developing OHSS does not affect subsequent ovarian quiescence.     

Recovery of corpus luteum function after prolonged deprivation from gonadotrophin stimulation

Three women with hypogonadotrophic hypogonadism, all desiringpregnancy, participated in a prospective open study attemptingto assess the ability of the human corpus luteum to recoverafter 7 days of deprivation from gonadotrophin stimulation.Follicular growth was induced by gonadotrophins. An endogenousluteinizing hormone (LH) surge was induced by the s.c. injectionof a gonadotrophin-releasing hormone agonist For luteal support,10 mg/day oral medroxyprogesterone acetate were given for 7days, after which a single i.m. injection of human chorionicgonadotrophin (HCG) was administered. Monitoring during thefollicular phase consisted of daily measurements of serum oestradiol,LH and follicle stimulating hormone (FSH) concentrations, andof follicular growth by trans-vaginal ultrasonography. Duringthe luteal phase, monitoring consisted of measurements of serumconcentrations of LH, FSH, oestradiol, progesterone, 17-hydroxy-progesteroneand -HCG. Ovulation and luteinization occurred in two patients,demonstrated by transient marked increases in serum progesteroneand 117-hydroxy-progesterone concentrations which decreasedto basal pre-ovulatory values and increased again followingthe administration of HCG 7 days later. In the third patient,ovulation and luteinization did not occur, and the subsequentadministration of HCG did not result in an increase in progesteroneconcentration. Of the two patients who ovulated, one conceivedand the second had a luteal phase of 15 days duration. Our preliminaryresults suggest that the human corpus luteum can be ’rescued‘and can function normally after 7 days of deprivation from gonadotrophinstimulation in patients with hypogonadotrophic hypogonadism.     

Serum inhibin levels in gonadotrophin stimulated in-vitro fertilization/gamete intra-fallopian transfer cycles.

Serum inhibin concentrations of 64 cycles of in-vitro fertilization--embryo transfer (IVF-ET) or gamete intra-Fallopian transfer (GIFT) have been analysed retrospectively. No significant difference was observed in serum inhibin levels of cycles stimulated with buserelin and human menopausal gonadotrophin (HMG) or HMG alone. During the late follicular phase, serum inhibin was higher in cycles resulting in pregnancy than in cycles without a pregnancy (peak values on day +1: 8.3 versus 6.4 IU/ml, respectively). The same difference was found between stimulation cycles resulting in a viable or a non-viable pregnancy (peak values on day +1: 8.3 versus 7.5 IU/ml). However, these differences were not significant. During the early luteal phase, serum inhibin values were similar in these groups of patients. Our results indicate that the use of the gonadotrophin-releasing hormone (GnRH) analogue buserelin, in combination with HMG, for ovarian stimulation does not affect inhibin production by granulosa cells in vivo. The late follicular and early luteal concentrations of serum inhibin have to be considered unsuitable as predictors in IVF/GIFT cycles with respect to pregnancy and pregnancy outcome.     

Insulin-like growth factor binding protein-1 and ovarian stimulation.

Serum concentrations of insulin-like growth factor binding protein-1 (IGFBP-1) were measured in 42 patients with tubal infertility undergoing two different regimens of ovarian stimulation for in-vitro fertilization. The first group comprised 24 women given a luteinizing hormone-releasing hormone agonist analogue (buserelin, LHRHa) on cycle days 1-4 followed by follicle-stimulating hormone and human menopausal gonadotrophin (LHRHa group). The second group of 18 women received clomiphene citrate and gonadotrophins (CC group). On the day of human chorionic gonadotrophin administration, the sum of follicular diameters (P less than 0.05) and the number of follicles punctured in the LHRHa group (P less than 0.01) were significantly higher than in the CC group. In spite of the greater number of follicles, the oestrogen levels were similar in both groups, but women in the LHRHa group had significantly higher serum IGFBP-1 concentrations during the last 5 days of stimulation. These results suggest that the stimulated preovulatory follicles may contribute to the elevation of serum IGFBP-1.     

Human prolactin release induced by follicle stimulating hormone, luteinizing hormone and human chorionic gonadotrophin

Plasma prolactin levels rise in stimulated cycles. To clarifythe effects of gonadotrophin on the lactotrophs, three studieswere performed. First, plasma concentrations of prolactin duringclomiphene citrate (CC)-human menopausal gonadotrophin (HMG)-humanchononic gonadotrophin (HCG) treatment of women enrolled forin-vitro fertilization (IYF) were compared with those duringHMG-HCG administration while under pituitary suppression witha gonadotrophin releasing hormone (GnRH) analogue (buserelin).Women suppressed with buserelin had higher basal levels of PRLin plasma (14.4 ± 4.3 nglml versus 6.9 ± 1.4 ng/ml,P<0.001). Only buserelin-suppressed women showed a significantrise in plasma prolactin before HCG administration, while bothpatient groups had marked prolactin peaks after HCG injection.This peak was higher in the buserelin group (71.9 ± 50.7ng/ml versus 52.6 ± 29.7 ng/ml). The second study showedthat plasma levels of prolactin of 6 post- menopausal womenwere significantly increased 48 h after an injection of 5000IU HCG, i.m. (24.9 ± 17.4 ng/ml versus 12.4 ±6.2 ng/ml P<0.05). Third, plasma prolactin was studied in5 women over 30 days after surgical castration. An upward trendwas observed similar to that of endogenous gonadotrophin, withthe change in prolactin values closely correlating with thechange in concentrations of follicule stimulating hormone (P<0.005).All these findings suggest that human gonadotrophins stimulatelactotrophs.     

Regulation of corpus luteum function

The effects have been studied of different ovulation inductionregimens [either domiphene citrate or buserelin in combinationwith human menopausal gonadotrophin (HMG)] on the circulatingconcentrations of progesterone, oestradiol, relaxin and humanchorionic gonadotrophin (HCG) during the first trimester ofpregnancy. Ovulation induction with clomiphene resulted in elevatedconcentrations of gonadotrophins in both phases of the cycle,while during ovulation induction with buserelin, gonadotrophinconcentrations were elevated in the follicular phase only. Theconcentrations of all corpus luteum products were greater inclomiphene pregnancies compared with spontaneous pregnancies,but only oestradiol and relaxin concentrations were greaterin clomiphene pregnancies compared with buserelin pregnancies.The concentrations of HCG were significantly reduced in clomiphenepregnancies compared to natural pregnancies. Relaxin concentrationswere significantly higher from 7 weeks gestation in buserelincompared with spontaneous pregnancies, while progesterone, oestradioland HCG concentrations were not consistently different. Consistentassociations were found between relaxin and HCG concentrationsin spontaneous pregnancies and between the concentrations ofrelaxin and both progesterone and oestradiol in pregnanciesachieved after ovulation induction. These data suggest that(i) given the similarity in the circulating concentrations ofHCG, the relatively lower circulating gonadotrophin concentrationsduring the luteal phase of the cycle of conception result inreduced circulating concentrations of oestradiol and relaxin;while in the case of relaxin this effect is partially reversible,there is no evidence that this is so for oestradiol; (ii) synthesisof progesterone in the corpus luteum is less affected by lowerconcentrations of gonadotrophins during the luteal phase; (iii)ovulation induction with clomiphene results in pregnancies withlower concentrations of HCG, suggesting that trophoblast functionmay be impaired; and (iv) corpus luteum function is linked withplacental steroidogenesis.     

Lipoprotein(a) changes during natural menstrual cycle and ovarian stimulation with recombinant and highly purified urinary FSH

This prospective, randomized, controlled study compared the effects of recombinant human FSH (r-hFSH) and highly purified urinary FSH (u-hFSH HP) on lipoprotein(a) [Lp(a)] concentrations in women undergoing ovarian stimulation. Fifty infertile women were randomly allocated into two equally sized treatment groups (n = 25 per group). Thirty normal ovulation women were recruited as controls. The infertile women received u-hFSH or r-hFSH 150 IU/day starting on cycle day 2. From cycle day 6 the dose was adjusted according to ovarian response. Human chorionic gonadotrophin 10,000 IU was administered once there was at least one follicle > or =18 mm in diameter. The luteal phase was supported with progesterone 50 mg/day for at least 15 days. Repeated measurements of Lp(a) concentrations were performed during both stimulated and natural cycles. A significant increase in luteal phase Lp(a) concentrations was detected in the stimulated cycles, whereas no significant changes in serum Lp(a) concentrations were observed during natural cycles. There were no significant differences between the urinary and recombinant FSH effects on serum Lp(a). The luteal Lp(a) increase was transitory because after 1 month Lp(a) concentrations returned to baseline values if pregnancy failed to occur; in pregnant women persistent increased Lp(a) concentrations were found at the 8th week. The percentage changes in serum Lp(a) were positively correlated with the luteal progesterone increase (r = 0.40, P < 0.05), but not with follicular or luteal oestradiol increase. The women with low baseline Lp(a) (< or =5 mg/dl) had a greater increase of the Lp(a) concentrations at midluteal phase than women with baseline Lp(a) >5 mg/dl. In conclusion, the recombinant or urinary hFSH administration does not directly influence Lp(a) concentrations. The luteal Lp(a) increase in stimulated cycles is not related to gonadotrophin treatment per se, but appears to be related to the high luteal progesterone concentrations, physiologically or pharmacologically determined. Our results also suggest that the sensitivity to the progesterone changes could be related to apolipoprotein(a) phenotype.     

Induction of follicular growth and production of a normal hormonal milieu in spite of using a constant low dose of luteinizing hormone in women with hypogonadotrophic hypogonadism

This study was designed to examine ovarian performance, i.e.follicular growth, normal steroidogenesis and luteal phase function,following the administration of multiple increasing doses ofhuman follicle stimulating hormone (FSH) with a constant lowdose of luteinizing hormone (LH) in women with isolated hypogonadotrophichypogonadism. Human meno–pausal gonadotrophin (HMG) wasused in the first treatment cycle, starting with 150 IU of LHand 150 IU of FSH per day, for 7 days. The dose was increaseddaily with 75 IU of LH and 75 IU of FSH for another 7 days ifno response was detected by serial ultrasound measurements andserumoestradiol determinations. In the second treatment cycle,a constant dose of 75 IU of LH (using HMG) was administeredper day and up to 150 IU of FSH (using urofollitrophin) wassupplemented. If no response was detected after 7 days of treatment,the dose of FSH was increased. For the final stage of ovulationinduction, human chorionic gonadotrophin (HCG) was administeredin the presence of at least one follicle >17 mm in diameterbut with no more than three follicles >16mm in diameter.To verify the adequacy of the luteal phase, a pharmacokinetic/pharmacodynamicstudy of -HCG, oestradiol and progesterone was performed followingthe second treatment cycle only. Ovarian stimulation using aconstant dose of 75 IU of LH and increasing doses of FSH upto 225 IU, resulted in normal follicular growth and hormonalmilieu. Both women showed normal luteal phase oestradiol andprogesterone production and both women conceived following thesecond treatment cycle     

Comparison of LH concentrations in the early and mid-luteal phase in IVF cycles after treatment with HMG alone or in association with the GnRH antagonist Cetrorelix

Luteinizing hormone (LH) is mandatory for the maintenance of the corpus luteum. Ovarian stimulation for IVF has been associated with a defective luteal phase. The luteal phases of two groups of patients with normal menstrual cycles and no endocrinological cause of infertility were retrospectively analysed in IVF cycles. Thirty-one infertile patients stimulated with human menopausal gonadotrophins (HMG) for IVF to whom the gonadotrophin-releasing hormone (GnRH) antagonist Cetrorelix 0.25 mg was also administered to prevent the LH surge (group I) were compared with 31 infertile patients stimulated with HMG alone (group II). Despite differences in the stimulation outcome, luteal LH serum concentrations were similar in the two groups. LH values dropped from 2.3 +/- 1 IU/l on the day of human chorionic gonadotrophin (HCG) administration to 1.1 +/- 0.7 IU/l on day HCG +2 in group I (P < 0.0001) and from 5.1 +/- 3 to 1.2 +/- 1.7 IU/l (P < 0.0001) in group II. In the mid-luteal phase, LH concentrations were low in both groups. Our results suggest that suppressed LH concentrations in the early and mid-luteal phase may not be attributed solely to the GnRH-antagonist administration. Pituitary LH secretion may be inhibited by supraphysiological steroid serum concentrations via long-loop feedback and/or by the central action of the exogenously administered HCG via a short-loop mechanism.     

Triggering of ovulation in human menopausal gonadotrophin-stimulated cycles: comparison between intravenously administered gonadotrophin-releasing hormone (100 and 500 {micro}g), GnRH agonist (buserelin, 500 {micro}g) and human chorionic gonadotrophin (10 000 IU)

We studied the peri-ovulatory and luteal phases in 38 humanmenopausal gonadotrophin (HMG)-stimulated cycles, in which ovulationwas triggered with four different i.v. bolus ovulation triggers:100 µg gonadotrophin-releasing hormone (GnRH; group A,n = 9), 500 µg GnRH agonist (GnRHa; group B, n = 10),10 000IU human chorionic gonadotrophin (HCG; group C, n = 10)and 500 µg GnRH (group D, n = 9). Endogenous luteinizinghormone (LH) surges occurred in all cycles of groups A, B andD. The rise was slowest but highest in group B (P < 0.0001)and lowest in group A. Although the t₀ serum oestradiol valueswere similar in all groups, day +8 oestradiol and day +4 and+8 progesterone concentrations were higher in group C (P <0.05). At day +4 and +8, serum LH concentrations were lowest(P < 0.01) but follicle stimulating hormone (FSH) concentrationswere higher. Clinically, day +8 luteal scores showed a moreconspicuous degree of ovarian hyperstimulation in the HCG group(P = 0.0292). Luteal insufficiency, defined as cycles with progesteroneconcentrations of <8 ng/ml, occurred much more frequentlyin groups A, B and D than in group C (day +4: P < 0.0003;day +8: P < 0.0001), despite progesterone supplementation.Three pregnancies (one in group C and two in group D) and onemoderate case of ovarian hyperstimulation syndrome (OHSS) (ina non-conceptional group D cycle) occurred. These findings showthat (i) ovulation occurs and pregnancy can be achieved followingan endogenous LH surge induced by GnRH and its agonists, (ii)a high frequency of luteal insufficiency occurs in such cycleseven with luteal supplementation and (iii) OHSS cannot be totallyprevented by this approach, although cycles with an endogenousLH surge in general result in fewer subclinical signs of ovarianhyperstimulation.     

Clinical and endocrinological changes in women following ovulation induction using buserelin acetate/human menopausal gonadotrophin augmented with biosynthetic human growth hormone.

Biosynthetic human growth hormone added to an ovarian stimulation regime of human menopausal gonadotrophin (HMG) for IVF treatment improves the response of women who were previously resistant. This study investigated the efficacy of growth hormone (GH)/buserelin/HMG treatment in women with a previous normal response to buserelin/HMG stimulation. Ten patients (28-36 years, mean 32.5 years) were treated with GH (6 IU/day) plus buserelin/HMG. A control group of 10 women (28-37 years mean 31.0 years) received buserelin/HMG alone. All were given buserelin 500 micrograms and 2 ampoules (150 IU) HMG daily once pituitary suppression had been confirmed. There was no improvement in the GH group as assessed by follicular growth rate or number, oocyte number per woman and pregnancy rate. There was no effect of GH upon the serum oestradiol level and the follicular fluid levels of oestradiol, GH and inhibin. Serum IGF-1 increased significantly during GH administration, returning to pre-treatment levels 2 days after the last dose of GH. Follicular IGF-1 was much higher in the GH-treated group than the controls. Significant correlations were found in the GH-treated group between follicular fluid GH and follicular fluid oestradiol concentrations and between follicular GH and follicular size. Follicular IGF-1 was correlated with the serum IGF-1 concentration on day 8 of the GH/HMG treatment. In conclusion GH/buserelin/HMG treatment in women with a previous normal response to buserelin/HMG stimulation increased their serum and follicular IGF-1 concentrations. However, it does not improve the clinical ovarian response or the follicular secretion of oestradiol or inhibin.