Flexible protocol for administration of human follicle-stimulating hormone with gonadotropin-releasing hormone antagonist**Supported in part by the Contraceptive Research and Development (CONRAD) Program, Eastern Virginia Medical School, under a Cooperative Agreement (DPE-2044-A-00-6063-00) with the United States Agency for International Development (A.I.D.). The views expressed by the author(s) do not necessarily reflect the views of A.I.D

Investigating dosage effects of ovulation inhibitors on oocyte maturation in assisted reproductive technology: A retrospective study among patients with normal ovarian reserve

The judicious selection of ovulation inhibitors in ovarian stimulation protocols is crucial for the success of assisted reproductive technology (ART). Herein, we investigate the dose-dependent effects of chlormadinone acetate (CMA) and cetrorelix, two distinct ovulation inhibitors, on oocyte maturation in patients with normal ovarian reserve, using univariable and multivariable Poisson regression analyses. Patients undergoing progestin-primed ovarian stimulation (PPOS) with CMA (n = 299) or gonadotropin-releasing hormone antagonist (GnRH-ant) with cetrorelix (n = 605) during their initial in vitro fertilization cycle were enrolled at our center from March 2018 to October 2020 (N = 904). The primary and secondary outcomes were the oocyte maturation and fertilization rates, respectively. After adjusting for several covariates including age, anti-Müllerian hormone levels, total gonadotropin dose, and type of trigger, we calculated the dose-dependent adjusted relative risk (aRR) and 95% confidence interval (CI) for 1 mg of CMA or 0.25 mg of cetrorelix. In the PPOS group, the median age was 34.0 years, and the median total CMA dosage was 22 mg (interquartile range [IQR]: 18.0-32.0). In the GnRH-ant group, the median age was 35.0 years, and the median total cetrorelix dosage was 0.5 mg (IQR 0.5-0.5). The aRR of the maturation rate was 1.003 (95% CI: 0.999-1.007) with PPOS (p = 0.194) and 1.009 (95% CI: 0.962-1.059) with GnRH-ant (p = 0.717). The aRR of the fertilization rate was 1.002 (95% CI: 0.985-1.020) with PPOS (p = 0.783) and 1.022 (95% CI: 0.839-1.246) with GnRH-ant (p = 0.829). Collectively, these findings indicate that within the applied dosages, ovulation inhibitors do not significantly impact oocyte maturation or fertilization rates in patients with normal ovarian reserve. These valuable insights can be applied when designing ART protocols and may guide clinicians in optimizing infertility treatments.

The role of LHRH agonists and antagonists

Administration of GnRH analogues (agonists as well as antagonists) produces suppression of the pituitary---gonadal axis, thus inhibiting the secretion of LH, FSH and sexual steroids. For this reason, analogs are indicated in all those clinical situations where suppression of gonadotrophins (precocious puberty, contraception) or of sexual steroids (endometriosis, prostate hyperplasia, cancer, uterine fibroids) is desired. For several years GnRH agonists have been used in combination with gonadotrophins for ovarian stimulation for assisted reproduction in order to control premature LH surges and to reduce cancellation rate with improvement of the pregnancy rate per cycle. This effect is obtained after 2 weeks of agonist administration. The immediate suppression of the pituitary achieved by GnRH antagonists without an initial stimulatory effect is the main advantage of these compounds over the agonists. The prevention of a premature LH surge by GnRH antagonists can be obtained by multiple dose or by a single administration. Both protocols offer the following advantages over the agonists: they require fewer ampoules of gonadotrophins, shorter duration of stimulation, there is a preserved pituitary response to GnRH, less risk of ovarian hyperstimulation syndrome and the luteal phase seems to be more preserved. The main disadvantages of the antagonists are that they are expensive and that pregnancy rate appears to be slightly lower than with the agonists. GnRH antagonists will probably replace agonists in ovarian stimulation treatment for assisted reproduction techniques.

A prospective randomized comparison between long and discontinuous-long protocols of gonadotropin-releasing hormone agonist for in vitro fertilization

OBJECTIVE

To investigate the efficacy of a discontinuous-long protocol in an IVF program.

DESIGN

Prospective randomized study.

SETTING

University hospital.

PATIENT(S)

One hundred thirty-seven IVF cycles of 92 patients in an outpatient IVF program from April 1995 to December 1995.

INTERVENTION(S)

In the discontinuous-long protocol group (n = 68), GnRH agonist (GnRH-a) was administered from the luteal phase until cycle day 7, when pure FSH administration was begun. In the long protocol group (n = 69), GnRH-a was administered until the day before hCG administration.

MAIN OUTCOME MEASURE(S)

Serum LH and ovarian steroid hormone levels, and IVF outcome.

RESULT(S)

The period and the total dosage of hMG were increased in the discontinuous-long protocol group. Although the fertilization rate was similar under both protocols, the number of embryos transferred was smaller and the cancellation rate was higher in the discontinuous-long protocol group because of the greater failure of oocyte retrieval and fertilization. Serum E2 levels in the late follicular phase were lower in the discontinuous-long protocol group.

CONCLUSION(S)

Early discontinuation of GnRH-a is not beneficial because of its adverse effects on follicular development.

Control of the preovulatory Luteinizing Hormone surge by Gonadotropin-Releasing Hormone antagonists: prospects for clinical application

The preovulatory LH surge of the primate menstrual cycle represents a number of positive influences, a major component of which is a direct action of estradiol on the anterior pituitary lobe. Whether the LH surge also requires a corresponding burst of GnRH release from the hypothalamus has been debated. After many years of investigation, there is now conclusive evidence that a midcycle GnRH surge does occur in the primate. This is supported by studies in women with normal ovulatory cycles that demonstrate that blockade of the GnRH receptor by potent GnRH antagonists administered within 1-2 days of the expected midcycle can delay the LH surge. The ability to prevent the positive feedback effects of estradiol by GnRH antagonists is being employed for the controlled induction of follicular development and ovulation in the treatment of infertility and in in vitro fertilization programs.