In vitro fertilization cycle outcome after coasting in gonadotropin-releasing hormone (GnRH) agonist versus GnRH antagonist protocols

The effect of early coasting on blastocyst development and outcome following blastocyst transfer in IVF/ICSI programme

Objective

Coasting is a well-known strategy to decrease severity of Ovarian Hyperstimulation Syndrome (OHSS). The purpose of this study is to assess the effect of Coasting on blastocyst development and subsequent clinical outcome following exclusive blastocyst transfer.

Methods

We conducted an observational cohort study of patients having blastocyst transfer following IVF/ICSI treatment. Patients undergoing IVF/ICSI cycles were included in the study. Patients at risk of OHSS were coasted. Outcome following exclusive blastocyst transfer was compared between coasted and non-coasted groups. The main outcome measures were the rate of blastocyst development and live birth rates in coasted and non-coasted cycles. Within coasted cycles, outcome was further analysed based on coasting duration and serum estradiol (E₂) drop (difference between peak E₂ and E₂ on day of HCG).

Results

A total of 166 coasted cycles and 656 non-coasted cycles had blastocyst transfer. Blastocyst development (45.97% vs. 48.6%) and live birth rates (45.18% vs. 43.44%) were not significantly different between coasted and non-coasted cycles. The overall clinical pregnancy (54.21% vs. 49.08%) and implantation rates (43.95% vs. 39.54%) following blastocyst transfer in coasted cycles were not significantly different from those of non-coasted cycles.

Conclusion

Coasting duration up to 6 days and drop in serum E₂ levels did not compromise blastocyst development, implantation, clinical pregnancy or live birth rates. We conclude that coasting with subsequent blastocyst transfer can be used as an effective strategy in patients at risk of OHSS with no detrimental effects on blastocyst development or live birth outcome.

Does ovarian stimulation regimen affect IVF outcome? a two-centre, real-world retrospective study using predominantly cleavage-stage, single embryo transfer

In this study, ovarian stimulation using highly purified human menopausal gonadotrophin (HP-HMG) and recombinant FSH (rFSH) for IVF were compared in two large assisted reproduction technique centres in Sweden. A total of 5902 women underwent 9631 oocyte retrievals leading to 8818 embryo transfers (7720 on day 2): single embryo transfers (74.2%); birth rate per embryo transfer (27.7%); multiple birth rate (5.0%); incidence of severe ovarian hyperstimulation syndrome (0.71%). Compared with ovarian stimulation with rFSH, women who received HP-HMG were older, had higher dosages of gonadotrophins administered, fewer oocytes retrieved and more embryos transferred. After multivariate analysis controlling for age and generalized estimating equation model, no differences were found in delivery outcomes per embryo transfers between HP-HMG and rFSH, independent of gonadotrophin releasing hormone analogue (GnRH) used. Logit curves for live birth rate suggested differences for various subgroups, most prominently for women with high oocyte yield or when high total doses were used. Differences were not significant, perhaps owing to skewed distributions of the FSH compounds versus age and other covariates. These 'real-life patients' had no differences in live birth rate between HP-HMG and rFSH overall or in subgroups of age, embryo score, ovarian sensitivity or use of GnRH analogue regimen.

The Effect of Coasting on Intracytoplasmic Sperm Injection Outcome in Antagonist and Agonist Cycle

Background

Coasting can reduce the ovarian hyperstimulation syndrome (OHSS) risk in ovulation induction cycles before intracytoplasmic sperm injection (ICSI). This study aimed to investigate the effect of gonadotropin-releasing hormone (GnRH) agonist and GnRH antagonist protocols to controlled ovarian hyperstimulation (COH) cycles with coasting on the parameters of ICSI cycles and the outcome.

Materials and Methods

In a retrospective cohort study, 117 ICSI cycles were per- formed and coasting was applied due to hyperresponse, between 2006 and 2011. The ICSI outcomes after coasting were then compared between the GnRH agonist group (n=91) and the GnRH antagonist group (n=26).

Results

The duration of induction and the total consumption of gonadotropins were found to be similar. Estradiol (E₂) levels on human chorionic gonadotropin (hCG) day were found higher in the agonist group. Coasting days were similar when the two groups were compared. The number of mature oocytes and the fertilization rates were similar in both groups; however, the number of grade 1 (G1) embryos and the number of transferred embryos were higher in the agonist group. Implantation rates were significantly higher in the antagonist group compared to the agonist group. Pregnancy rates/embryo transfer rates were higher in the antagonist group; however, this difference was not statistically significant (32.8% for agonist group vs. 39.1% for antagonist group, P>0.05).

Conclusion

The present study showed that applying GnRH-agonist and GnRH-antago- nist protocols to coasted cycles did not result in any differences in cycle parameters and clinical pregnancy rates.

The prevention of ovarian hyperstimulation syndrome

OBJECTIVE

To review the clinical aspects of ovarian hyperstimulation syndrome and provide recommendations on its prevention.

OPTIONS

Preventative measures, early recognition, and prompt systematic supportive care will help avoid poor outcomes.

OUTCOMES

Establish guidelines to assist in the prevention of ovarian hyperstimulation syndrome, early recognition of the condition when it occurs, and provision of appropriate supportive measures in the correct setting.

EVIDENCE

Published literature was retrieved through searches of Medline, Embase, and the Cochrane Library from 2011 to 2013 using appropriate controlled vocabulary ([OHSS] ovarian hyperstimulation syndrome and: agonist IVF, antagonist IVF, metformin, HCG, gonadotropin, coasting, freeze all, agonist trigger, progesterone) and key words (ovarian hyperstimulation syndrome, ovarian stimulation, gonadotropin, human chorionic gonadotropin, prevention). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies published in English. There were no date restrictions. Searches were updated on a regular basis and incorporated in the guideline to February 2013. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). Summary Statements 1. The particular follicle-stimulating hormone formulation used for ovarian stimulation does not affect the incidence of ovarian hyperstimulation syndrome. (I) 2. Coasting may reduce the incidence of severe ovarian hyperstimulation syndrome. (III) 3. Coasting for longer than 3 days reduces in vitro fertilization pregnancy rates. (II-2) 4. The use of either luteinizing hormone or human chorionic gonadotropin for final oocyte maturation does not influence the incidence of ovarian hyperstimulation syndrome. (I) 5. There is no clear published evidence that lowering the human chorionic gonadotropin dose will result in a decrease in the rate of ovarian hyperstimulation syndrome. (III) 6. Cabergoline starting from the day of human chorionic gonadotropin reduces the incidence of ovarian hyperstimulation syndrome in patients at higher risk and does not appear to lower in vitro fertilization pregnancy rates. (II-2) 7. Avoiding pregnancy by freezing all embryos will prevent severe prolonged ovarian hyperstimulation syndrome in patients at high risk. (II-2) 8. Pregnancy rates are not affected when using gonadotropin-releasing hormone (GnRH) agonists in GnRH antagonist protocols for final egg maturation when embryos are frozen by vitrification for later transfer. (II-2) Recommendations 1. The addition of metformin should be considered in patients with polycystic ovarian syndrome who are undergoing in vitro fertilization because it may reduce the incidence of ovarian hyperstimulation syndrome. (I-A) 2. Gonadotropin dosing should be carefully individualized, taking into account the patient's age, body mass, antral follicle count, and previous response to gonadotropins. (II-3B) 3. Cycle cancellation before administration of human chorionic gonadatropin is an effective strategy for the prevention of ovarian hyperstimulation syndrome, but the emotional and financial burden it imposes on patients should be considered before the cycle is cancelled. (III-C) 4. Gonadotropin-releasing hormone (GnRH) antagonist stimulation protocols are recommended in patients at high risk for ovarian hyperstimulation syndrome (OHSS). The risk of severe OHSS in patients on GnRH antagonist protocols who have a very robust ovarian stimulation response can be reduced by using a GnRH agonist as a substitute for human chorionic gonadotropin to trigger final oocyte maturation. (I-B) 5. A gonadotropin-releasing hormone (GnRH) antagonist protocol with a GnRH agonist trigger for final oocyte maturation is recommended for donor oocyte and fertility preservation cycles. (III-C) 6. Albumin or other plasma expanders at the time of egg retrieval are not recommended for the prevention of ovarian hyperstimulation syndrome. (I-E) 7. Elective single embryo transfer is recommended in patients at high risk for ovarian hyperstimulation syndrome. (III-C) 8. Progesterone, rather than human chorionic gonadotropin, should be used for luteal phase support. (I-A) 9. Outpatient culdocentesis should be considered for the prevention of disease progression in severe ovarian hyperstimulation syndrome. (II-2B).

GnRH analogues in the prevention of ovarian hyperstimulation syndrome

The GnRH analogue (agonist and antagonist GnRH) changed ovarian stimulation. On the one hand, it improved chances of pregnancy to obtain more oocytes and better embryos. This leads to an ovarian hyper-response, which can be complicated by the ovarian hyperstimulation syndrome (OHSS). On the other hand, the GnRH analogue can prevent the incidence of OHSS: GnRH antagonist protocols, GnRH agonist for triggering final oocyte maturation, either together or separately, coasting, and the GnRH analogue may prove useful for avoiding OHSS in high-risk patients. We review these topics in this article.