Use of a gonadotropin-releasing hormone agonist during ovarian stimulation leads to significant concentrations of peptide in follicular fluids

Efficacy and safety of long-acting GnRH agonists in in vitro fertilization and embryo transfer

The introduction of gonadotrophin-releasing hormone (GnRH) agonists combined with gonadotrophins is considered to be one of the most significant events in the development of in vitro fertilization and embryo transfer (IVF-ET) programmes. This article reviews the use of GnRH agonists in IVF-ET programmes and the efficacy and safety of long-acting GnRH agonists. The use of agonists results in higher clinical pregnancy rates, more supernumerary embryos for cryopreservation and allows convenient programming of oocyte recovery. There are different types of agonist and ovarian stimulation protocol available for clinical use. Recent meta-analysis of the Cochrane database has demonstrated the superiority of the long protocols over the short and ultra-short protocols for GnRH agonist use in IVF and GIFT. The depot injection offers increased clinical and patient compliance and improves efficacy of pituitary downregulation. However, compared with short-acting agonists, the depot preparations are associated with a longer period of stimulation and higher doses of gonadotrophins. To date, there is no evidence of an increased risk of pregnancy wastages or teratogenicity in human pregnancies exposed to long-acting agonists.

Clinical and endocrine response to the withdrawal of gonadotropin-releasing hormone agonists during prolonged coasting

OBJECTIVE

To compare the clinical and endocrine response of cycles in which GnRH agonists (GnRH-a) were stopped with cycles in which the agonists were continued during coasting.

DESIGN

Retrospective study of stimulation cycles using flare and luteal agonist protocols.

SETTING

Academic.

PATIENT(S)

Fifty-nine IVF and intracytoplasmic sperm injection (ICSI) treatment cycles in 57 women, coasted for 3 or more days.

INTERVENTION(S)

The GnRH-a were withdrawn when E(2) levels continued to increase during coasting.

MAIN OUTCOME MEASURE(S)

Hormone concentrations, ultrasound findings, cycle cancellation, ovarian hyperstimulation syndrome (OHSS), oocyte retrieval, fertilization, embryo transfer, and clinical pregnancy rates (PR).

RESULT(S)

In the GnRH-a withdrawn group E(2) levels decreased by 63% (18,043-6,656 pmol/L) without cycle cancellations or cases of severe OHSS. In the agonist continuation group, the spontaneous E(2) decrease was 29% (14,205-10,132 pmol/L) with cycle cancellation and severe OHSS rates of 9.5% (4/42) and 4.8% (2/42), respectively. Oocyte retrieval, fertilization, embryo transfer, and clinical PRs were not compromised by stopping the agonists. Variations in the dynamic responses of FSH, LH, anti-Müllerian hormone, P, and androstenedione (A) levels in these cycles are described.

CONCLUSION(S)

Withdrawal of GnRH-a during coasting interrupted increasing E(2) levels, prevented cycle cancellation, and mitigated the risk of OHSS in this high risk group without compromising oocyte retrieval, fertilization, embryo transfer, or PRs.

Impact of leuprolide acetate on luteal phase function in women undergoing controlled ovarian hyperstimulation and intrauterine insemination

OBJECTIVE

To determine if the combination of leuprolide acetate (LA) and human menopausal gonadotropin (hMG) results in luteal phase dysfunction.

DESIGN

A prospective, randomized clinical trial.

SETTING

A tertiary care university fertility center.

PATIENT(S)

One hundred thirty-five couples with various etiologies of infertility.

INTERVENTION(S)

Patients were prospectively randomized to receive either hMG and intrauterine insemination (IUI) or luteal phase down-regulation with LA, hMG, and IUI.

MAIN OUTCOME MEASURE(S)

Serum luteal phase progesterone (P) and luteal phase estradiol (E2) were obtained 9 days after hCG administration. Twenty-four-hour urinary P and luteinizing hormone (LH) were analyzed 9 days after human chorionic gonadotropin (hCG). Endometrial biopsies were performed 11 days after hCG and evaluated for luteal phase defects (LPD) using Noyes' criteria.

RESULT(S)

No significant differences in the incidence of LPD (11.9% vs. 13.9%), cycle fecundity (16.6% vs. 16.3%), or luteal phase hormone profiles were observed between the groups receiving and not receiving LA. A significant difference in E2 levels (on the day of hCG administration) between cycles with a luteal phase defect (967 pg/mL +/- 106) and without a luteal phase defect (1,422 pg/mL +/- 83) was observed (P<.05).

CONCLUSION(S)

Pituitary down-regulation with LA combined with hMG did not result in luteal phase dysfunction. The E2 levels on the day of hCG administration in both groups were lower in women with documented luteal phase defects.

Inhibition of in vivo and in vitro fertilization in rodents by gonadotropin-releasing hormone antagonists

We have examined the effect of two GnRH antagonists, Ac-D-Nal(1)-Cl-D-Phe(2)-3-Pyr-D-Ala(3)-Arg(5)-D-Glu(AA)(6)-GnRH (Nal-Glu) and Ac(3,4)-dehydro-Pro(1),-p-fluoro-D-Phe(2),D-Trp(3,6)-GnRH (4pF), on in vivo and in vitro fertilization in rodents. Female rats were treated in the afternoon of proestrus with 2 micro l of Nal-Glu or 4pF (0.5 and 5 mM) injected directly into one oviductal horn (experimental); saline was injected into the contralateral horn (control). Females were then mated and the oviducts were perfused for egg and sperm recovery. The results indicate that both antagonists inhibited in vivo fertilization. Thus, the percentage of fertilized eggs in control oviducts ranged from 92% +/- 5% to 100% +/- 0%, whereas in treated oviducts, fertilization ranged from 25% +/- 6% to 73% +/- 5%. GnRH antagonists did not interfere with the process of ovulation, sperm migration to the site of fertilization, or early embryo development. In additional experiments with mice, GnRH antagonists inhibited in vitro fertilization. One fertilization event that was specifically inhibited by GnRH antagonists was the process of sperm binding to the zona pellucida. This step was precisely monitored using the hemizona assay. GnRH antagonists did not affect sperm movement or acrosomal status. These observations indicated that local treatment with GnRH antagonists inhibit in vivo fertilization and give additional support to the idea that endogenous GnRH may play an important role during fertilization by increasing the efficiency of sperm-zona binding.

The effects of gonadotropin-releasing hormone agonist on androstenedione production and follicular development during controlled ovarian hyperstimulation

PURPOSE

We performed a prospective randomized study to assess the effects of a GnRH agonist (GnRH-a) on follicular development and steroidogenesis during controlled ovarian hyperstimulation (COH).

METHODS

Patients undergoing in vitro fertilization (IVF) for tubal infertility received human menopausal gonadotropin (hMG) stimulation with or without the GnRH-a, buserelin, beginning in the midluteal phase of the prior cycle. We analyzed serum hormone levels, follicular development, and outcome of IVF.

RESULTS

The mean number of retrieved oocytes was significantly greater, and the implantation rate per embryo was significantly higher, in the GnRH-a/hMG group (n = 101) than in the hMG-only group (n = 97). The concentration of androstenedione (A) and the A/estradiol ratio in the serum were significantly lower in the GnRH-a treatment group throughout the follicular phase.

CONCLUSIONS

The concomitant use of GnRH-a during COH prevents atretic change of the follicles and enhances follicular development by reducing androgen accumulation, resulting in a higher developmental competence of the oocytes.

Long-term down-regulation does not improve pregnancy rates in an in vitro fertilization program

OBJECTIVE

To investigate the effects of long-term down-regulation (4 months) used in combination with gonadotropin ovarian stimulation for IVF-ET.

DESIGN

Prospective randomized study.

SETTING

Assisted Reproduction Unit of the Hospital Clinic i Provincial in Barcelona, a tertiary care setting.

PATIENT(S)

Thirty pairs of IVF patients who were matched for age, indication for IVF, and number of attempts.

INTERVENTION(S)

Women were randomized to receive a standard long protocol of SC leuprolide acetate (n = 30, group L) or a monthly injection of leuprolide acetate depot for 4 months (n = 30, group D) before gonadotropin stimulation.

MAIN OUTCOME MEASURE(S)

Ovarian response and IVF outcome.

RESULT(S)

Days of ovarian stimulation, follicular recruitment and growth during gonadotropin treatment, and the endometrial thickness on the day of hCG administration were similar for the 2 groups of IVF patients. However, the serum concentration of E2 was significantly higher in group L even though group D received a higher total dose of gonadotropins. The number of follicles punctured, the number of oocytes retrieved, the number of oocytes fertilized, the number of embryos suitable for replacement and cryopreservation, the number of patients with ET, and implantation and clinical pregnancy rates were similar for groups L and D. However, the percentage of metaphase II oocytes was significantly higher in group L than in group D.

CONCLUSION(S)

Long-term down-regulation does not improve pregnancy rates in a general IVF program.

Effects of a long-acting gonadotropin-releasing hormone analog on the pituitary-ovarian-adrenal axis in women with severe hirsutism

We evaluated modifications in the pituitary-ovarian-adrenal axis in severely hirsute women after administration of the gonadotropin-releasing hormone analog (GnRHa), D-Trp-6-luteinizing hormone-releasing hormone (LHRH) (Triptorelin) in a prospective study at a tertiary hospital. A total of 20 hirsute women aged 19 to 38 years were included. Hyperandrogenism of adrenal origin was excluded in all subjects. Patients received 3.75 mg D-Trp-6-LHRH intramuscularly (Decapeptyl 3.75; Lasa-Ipsen, Barcelona, Spain). Serum levels of follicle-stimulating hormone (FSH), LH, estradiol (E2), prolactin (PRL), testosterone (T), androstenedione (delta 4 An), dehydroepiandrosterone sulfate (DHEAS), 17-OH-progesterone (17-OHP), and sex hormone-binding globulin (SHBG) were determined before GnRHa administration, 24 and 48 hours after, and on days 7, 15, 30, and 45. GnRHa suppresses FSH, LH, and E2 in all women. Unexpectedly, adrenal steroids showed a flare-up phenomenon in the first days and subsequent decrease to lower values than before GnRHa administration. SHBG showed slight changes. After GnRHa, patients showed a significant decrease in T and delta 4 An: these hormones were reduced to half the basal levels. We conclude that GnRHa can potentially be used in the treatment of hyperandrogenism to reduce androgen levels in hirsute women.

Prospective study of a modified gonadotropin-releasing hormone agonist long protocol in an in vitro fertilization program

OBJECTIVE

To determine if pituitary suppression is still maintained if GnRH agonist (GnRH-a) is discontinued as gonadotropin stimulation is begun in a long protocol.

DESIGN

Prospective, randomized study.

SETTING

An outpatient IVF-GIFT program.

PATIENTS

One hundred seventy-three patients entering an IVF-GIFT program.

INTERVENTIONS

Gonadotropin-releasing hormone agonist in long protocol was either discontinued or continued as gonadotropin stimulation was begun.

MAIN OUTCOME MEASURES

Luteinizing hormone (LH), E2, and P levels, egg numbers, fertilization rate, number of embryos transferred, day of gonadotropin stimulation, and pregnancy rates (PRs).

RESULTS

Pituitary suppression was maintained although GnRH-a was discontinued as gonadotropin stimulation was begun. No spontaneous LH surge was seen, and PRs were increased in the IVF patients.

CONCLUSION

This study indicates that the advantages gained from use of GnRH-a in the long protocol are not compromised by its early discontinuation.

The comparison of two gonadotropin-releasing hormone agonists in an in vitro fertilization program

OBJECTIVE

To compare two gonadotropin-releasing hormone agonists (GnRH-a), buserelin acetate and leuprolide acetate [LA], used in combination with gonadotropins in ovarian stimulation for in vitro fertilization (IVF).

DESIGN

Randomized prospective study.

SETTING

Assisted Reproduction Unit of the Hospital Clínic i Provincial in Barcelona.

PATIENTS

Thirty-five pairs of IVF patients who were matched on age, indication, and number of attempts. These women were randomized to receive either buserelin acetate plus gonadotropins (group B) or LA plus gonadotropins (group L).

MAIN OUTCOME MEASURES

Luteolysis, ovarian response, and IVF outcome.

RESULTS

The mean time for total ovarian arrest and the total dose of gonadotropins and estradiol levels on the day of human chorionic gonadotropin administration were similar in the two groups of patients. The number of follicles punctured, the number of oocytes retrieved, and the percentage of mature oocytes in group L were significantly higher. The number of embryos suitable for replacement and cryopreservation was higher in group L compared with group B approaching statistical significance.

CONCLUSION

Our results warrant further studies to compare different GnRH-a as therapeutic tools in IVF.

Steroidogenesis in vitro of human granulosa-luteal cells pretreated in vivo with two gonadotropin releasing hormone analogs employing different protocols

We have previously observed impaired progesterone accumulation in vitro in response to human chorionic gonadotropin (hCG) by cells pretreated in vivo with a gonadotropin releasing hormone analog (GnRH-a). The present study was conducted in order to evaluate different protocols for GnRH-a in in vitro fertilization (IVF), employing two different available analogs. Granulosa-luteal cells were collected at ovum pick-up and stimulated with hCG. Buserelin (Bus) was employed as long (Bus-L) and short (Bus-S) protocol, and Leuprolide (Leu) was also used as long (Leu-L) and short (Leu-S) protocol. Progesterone accumulation in vitro was compared with cells treated with clomiphene citrate (CC) and gonadotropins. Maximal progesterone production was observed on culture day 6 using Bus-L in comparison to day 4 when clomiphene citrate was employed. While Leu-S showed a similar pattern of progesterone accumulation to clomiphene citrate, Leu-L and Bus-S had an intermediate pattern. The response to hCG was maximal on day 4 for the clomiphene citrate- and Leu-S-treated cells, while the rest of the protocols had a peak on day 6. In addition, hCG consistently stimulated progesterone production in all protocols except in Bus-L. These results confirm an altered progesterone accumulation in vitro when GnRH-a are used. The effect seems to be more evident in long protocols, especially when buserelin is used, suggesting a higher accumulation of the analog in follicular fluid.