IVF: induction of ovulation in poor responders

How fixed versus variable gonadotropin dose during controlled ovarian stimulation could influence the management of infertility patients undergoing IVF treatment: a national Delphi consensus

AIM

Define how and when fixed starting gonadotropin doses can be used in current clinical ART practices in Italy.

METHODS

A Delphi conference consisting of three rounds was performed in order to define the ideal clinical conditions in which fixed-gonadotropin-dose during COS should be applied. During the conference, 19 statements about the current ART practice were provided to a panel of twenty-nine national experts. Median score was 5 (IQ:4-6) in all Delphi rounds.

RESULTS

Eleven statements (57.9%) were classified as shareable with high-degree of convergence, 2 (10.5%) as shareable with low convergence and 6 (31.6%) as un-shareable with high convergence. The panel reached high consensus regarding some statements: (i) fixed FSH-dose in normoresponders and poor-responder, (ii) importance of predicting ovarian response before COS, considering multiple markers to select the right stimulation protocol for each patient, (iii) importance of therapy simplification and standardization to improve efficiency during COS. Moreover, a low-convergence was reached about use of GnRH antagonist as first treatment line and drug storage at room temperature. However from these findings, the debate remains open regarding some other statements: (a) usefulness of Bologna-criteria to define poor-responders; (b) efficacy to change always stimulation protocol after a failure IVF; (c) utility of AMH-dosed with standardized automatic mode to define normo-responder patients; (d) usefulness to modify the dosage of 12.5 IU/die during COS to improve stimulation effectiveness.

CONCLUSION

Controlled ovarian stimulation remains a challenging clinical step in Assisted Reproductive Technique, especially in some specific patient groups for which no clinical consensus is available. This study is the first attempt to describe the shared clinical opinion regarding the fixed versus variable gonadotropin dose in the real IVF practice.

A randomized, single-blind, prospective trial comparing three different gonadotropin doses with or without addition of letrozole during ovulation stimulation in patients with poor ovarian response

OBJECTIVE

The aim of this randomized controlled trial (RCT) was to investigate whether IVF outcomes would differ between patients with POR who received three different gonadotropin doses with or without the addition of letrozole during ovulation stimulation.

STUDY DESIGN

Only those who fulfilled two of the three Bologna criteria were included to the study. 95 patients met the inclusion criteria and agreed to participate in the study. In the first group, 31 patients were treated with 450IU gonadotropins. In the second group, 31 patients were treated with 300IU gonadotropins. The third group comprised 33 patients and was treated with 150IU gonadotropins in combination with letrozole.

RESULTS

The results indicate that differences in doses of hMG and rFSH in patients with POR result in a similar number of retrieved MII and fertilized oocytes, similar fertilization rates, number of transferred embryos, implantation, cancelation, chemical, clinical, and ongoing pregnancy rates.

CONCLUSIONS

Increasing the dose of gonadotropins during ovulation stimulation is an intuitively appealing approach when the patient is a poor responder. However, increasing the dose does not necessarily improve the reproductive outcome. Using a mild stimulation with addition of letrozole was as effective as stimulation with higher doses of gonadotropins alone in this patient population.

GnRH antagonist versus long GnRH agonist protocol in poor IVF responders: a randomized clinical trial

OBJECTIVE

To compare the efficacy of the long GnRH agonist and the fixed GnRH antagonist protocols in IVF poor responders.

STUDY DESIGN

This was a randomized controlled trial performed in the Iakentro IVF centre, Thessaloniki, from January 2007 to December 2011, concerning women characterised as poor responders after having 0-4 oocytes retrieved at a previous IVF cycle. They were assigned at random, using sealed envelopes, to either a long GnRH agonist protocol (group I) or a GnRH antagonist protocol (group II).

RESULTS

Overall 364 women fulfilled the inclusion criteria and were allocated to the two groups: finally 330 participated in our trial. Of these, 162 were treated with the long GnRH agonist protocol (group I), and 168 with the fixed GnRH antagonist protocol (group II). Numbers of embryos transferred and implantation rates were similar between the two groups (P=NS). The overall cancellation rate was higher in the antagonist group compared to the agonist group, but the difference was not significant (22.15% vs. 15.2%, P=NS). Although clinical pregnancy rates per transfer cycle were not different between the two groups (42.3% vs. 33.1%, P=NS), the clinical pregnancy rate per cycle initiated was significantly higher in the agonist compared to the antagonist group (35.8% vs. 25.6%, P=0.03).

CONCLUSIONS

Although long GnRH agonist and fixed GnRH antagonist protocols seem to have comparable pregnancy rates per transfer in poor responders undergoing IVF, the higher cancellation rate observed in the antagonist group suggests the long GnRH agonist protocol as the first choice for ovarian stimulation in these patients.

What should be the maximum FSH dose in IVF/ICSI in poor responders?

Various protocols of ovarian stimulation have been proposed for optimising IVF/ICSI results in women presenting with a poor response to controlled ovarian stimulation; however, achieving a good response to stimulation for this category of patients still remains a challenge. The most extensively employed strategy to improve follicular response in these so-called 'poor responders' involves the use of high doses of gonadotrophins. A small number of randomised controlled trials and retrospective studies have evaluated the effectiveness of the high-dose FSH regimes over a 300 IU threshold. The results of these studies have shown these approaches to be of little or no clinical benefit, although both the costs of treatment and side-effects were higher. There are other studies that have examined 450 IU FSH regimens or even more. This paper presents an overview in all these clinical trials, trying to evaluate the safest and most effective upper limit of FSH that may be used for controlled ovarian hyperstimulation.

Different ovarian stimulation protocols for women with diminished ovarian reserve

PURPOSE

To review the available treatments for women with significantly diminished ovarian reserve and assess the efficacy of different ovarian stimulation protocols.

METHODS

Literature research performed among studies that have been published in the Pubmed, in the Scopus Search Machine and in Cohrane database of systematic reviews.

RESULTS

A lack of clear, uniform definition of the poor responders and a lack of large-scale randomized studies make data interpretation very difficult for precise conclusions. Optimistic data have been presented by the use of high doses of gonadotropins, flare up Gn RH-a protocol (standard or microdose), stop protocols, luteal onset of Gn RH-a and the short protocol. Natural cycle or a modified natural cycle seems to be an appropriate strategy. Low dose hCG in the first days of ovarian stimulation has promising results. Molecular biology tools (mutations, single nucleotide polymorphisms (SNPs)) have been also considered to assist the management of this group of patients.

CONCLUSIONS

The ideal stimulation for these patients with diminished ovarian reserve remains a great challenge for the clinician, within the limits of our pharmaceutical quiver.

Role of gonadotropin-releasing hormone antagonists in poor responders

OBJECTIVE

To evaluate the role of GnRH antagonists in poor-responder protocols.

DESIGN

Literature review.

CONCLUSION(S)

The optimum stimulation protocol for poor responders is unknown. Although many IVF programs currently use GnRH antagonists for poor responders, there have been only four prospective, randomized trials comparing GnRH antagonists to alternate protocols. None of these studies had sufficient power to evaluate a difference in pregnancy rates (PRs), and in all four cases, IVF outcomes were comparable. Nevertheless, interest in the use of GnRH antagonists in poor responders has continued. GnRH antagonists may be associated with simpler stimulation protocols, lower gonadotropin requirements, reduced patient costs, and shorter downtimes between consecutive cycles. However, the greatest advantage of GnRH antagonists may lie in the ability to assess ovarian reserves immediately prior to deciding whether or not to initiate gonadotropin stimulation. The ability to respond to cycle-to-cycle variation in antral follicle counts may allow the optimization of oocyte yield and reduce cycle cancellation rates. It remains to be seen if this approach (initiating gonadotropins only in cycles where an adequate antral follicle count is present) also translates into higher clinical PRs for poor responders.

Bovine model of reproductive aging: Response to ovarian synchronization and superstimulation

The responsiveness of the hypothalamo-pituitary axis to steroid treatments for ovarian synchronization and the ovarian superstimulatory response to exogenous FSH was compared in 13-14 year old cows and their 1-4 year old young daughters. We tested the hypotheses that aging in cattle is associated with: (1) decreased follicular wave synchrony after estradiol and progesterone treatment; (2) delayed LH surge and ovulation in response to exogenous preovulatory estradiol treatment; (3) reduced superstimulatory response to exogenous FSH. Higher plasma FSH concentrations (P<0.01), and a tendency (P=0.07) for fewer 4-5 mm follicles at wave emergence were observed in old cows (n=10) than in young cows (n=9). The suppressive effect of estradiol/progesterone treatment on FSH was similar between old and young cows. Although the preovulatory LH surge in response to estradiol treatment was delayed in old than young cows (P=0.01), detected ovulation times were not different. No difference in ovarian superstimulatory response was detected between age groups, but old cows (n=8) tended (P=0.10) to have fewer large follicles (>or=9 mm) 12 h after last FSH treatment than in young cows (n=7). We concluded that pituitary and ovarian responsiveness to estradiol/progesterone synchronization treatment was similar between old and young cows, but aging was associated with a delayed preovulatory LH surge subsequent to estradiol treatment. Old cows tended to have fewer large follicles after superstimulatory treatment than young cows.

Modified natural cycle using GnRH antagonist can be an optional treatment in poor responders undergoing IVF

PURPOSE

To investigate the efficacy of gonadotrophin-releasing hormone (GnRH) antagonist supplementation during natural cycles in poor responders undergoing IVF-ET treatment.

METHODS

We retrospectively evaluated 540 cycles of 433 suitable patients who were divided by treatment protocol into modified natural, antagonist, and long agonist groups. There were 52 modified natural cycles with GnRH antagonist supplementation, 200 stimulated cycles with GnRH antagonist, and 288 long GnRH agonist cycles. Cycle characteristics and treatment outcomes were compared between the groups.

RESULTS

The mean number of oocytes retrieved in the modified natural group was significantly lower than in the stimulated antagonist and long agonist groups (1.4 +/- 0.5 vs. 2.3 +/- 1.1 and 2.5 +/- 1.1, respectively, p < 0.05). The respective implantation and pregnancy rates were 10% and 14.3%, 6.75% and 10.2%, and 7.4% and 10.6%. Cycle outcome and cycle properties were similar.

CONCLUSIONS

Modified natural IVF cycle with GnRH antagonist supplementation is a feasible alternative to ovarian stimulation protocols in poor responders.

An initial low response predicts poor outcome in in vitro fertilization/intracytoplasmic sperm injection despite improved ovarian response in consecutive cycles

OBJECTIVE

To study the predictive value of initial low response (LR) in IVF/intracytoplasmic sperm injection (ICSI).

DESIGN

Retrospective analysis.

SETTING

Two Finnish fertility centers.

PATIENT(S)

A total of 3,846 IVF/ICSI cycles performed from 1994 to 2002.

INTERVENTION(S)

Consecutive cycles in the same subject were identified. The study groups consisted of subjects who had three treatment cycles and at least one LR cycle (n = 80).

MAIN OUTCOME MEASURE(S)

Pregnancy rate (PR), total gonadotropin dose, and embryo quality.

RESULT(S)

Only 2.5% (2/80) of subjects had a LR in all three consecutive cycles. In 43 women an initial LR was followed by >/=1 normal response (NR) cycle, and in 35 women an initial NR was followed by >/=1 LR cycle. The PR/cycle was similarly low in women with an initial LR and an initial NR (10.1% vs. 16.2%). An increase in gonadotropin dose resulted in a higher number of oocytes in women with an initial LR (from 2.1 +/- 0.9 to 6.7 +/- 2.7) but the PR/cycle remained low, compared to the overall mean PR (27.2%). In cycles in which top quality embryos were transferred, subjects with an initial LR had a lower PR than women with an initial NR (17.8% vs. 41.2%).

CONCLUSION(S)

An initial LR is a predictor of poor outcome in subsequent cycles, even if ovarian response is improved by increasing the gonadotropin dose or a top quality embryo is replaced.

Use of follicle-stimulating hormone test to predict poor response in in vitro fertilization

OBJECTIVE

Optimized ovarian stimulation protocols are required for the success of in vitro fertilization (IVF). The purpose of this study was to estimate whether the ovarian reserve test using exogenous follicle-stimulating hormone (FSH) could predict ovarian response in IVF.

METHODS

This was a prospective observational study of 110 patients who underwent their first IVF cycle. The FSH test was administered as 150 IU of urinary FSH daily from day 3 to day 6 of the menstrual cycle preceding the IVF cycle for evaluation of the plasma estradiol level. Outcomes of IVF, including ovarian response, were analyzed.

RESULTS

A negative correlation was observed between the duration of stimulation and the result of the FSH test (r = -.238, P = .014) and between the dose of FSH per retrieved mature oocyte (metaphase II oocyte) and the result of the FSH test (r = -.308, P < .001). In addition, our results showed that the result of the FSH test was significantly lower in poor responders defined by FSH of 400 IU/metaphase II oocyte or greater (207 +/- 149 compared with 293 +/- 174 pg/mL, P = .007).

CONCLUSION

The FSH test can be a useful tool for determining the conditions of individualized clinical management plans and optimizing stimulation protocols in IVF.

GnRH antagonist in IVF poor-responder patients: results of a randomized trial

The aim of this prospective study was to evaluate the efficacy of gonadotrophin-releasing hormone antagonist (GnRH) in comparison with the standard long protocol in poor-responder patients. Sixty patients with poor ovarian response in previous treatment cycles were randomized into two groups: group A (n = 30) was stimulated with a standard long protocol, and group B (n = 30) received GnRH antagonist. Vaginal ultrasound was performed to evaluate ovarian response. There was a significantly reduced duration of ovarian stimulation (9.8 +/- 0.8 versus 14.6 +/- 1.2, P = 0.001) in group B in comparison with group A, and a reduced number of ampoules was used in group B (49.3 +/- 4.3 versus 72.6 +/- 6.8, P = 0.0001). In group B, the number of oocytes retrieved was significantly higher than in group A (5.6 +/- 1.6 versus 4.3 +/- 2.2, P = 0.02) and there was an increased number of follicles with a diameter >15 mm at human chorionic gonadotrophin administration in group B (P = 0.0001). Fewer cycles were cancelled with the use of an antagonist protocol. Five pregnancies (17% for embryo transfer) were obtained with GnRH antagonist protocol and two (7% for embryo transfer) with GnRH agonist protocol.

Alternative Approaches in the Management of Poor Response in Controlled Ovarian Hyperstimulation (COH)

Improving pregnancy rates in patients with many failed attempts remains a challenge during IVF-ET or ICSI-ET programs. The availability of good-quality oocytes is a prerequisite for good results in such programs. The use of a personalized protocol for controlled ovarian hyperstimulation (COH) that gives the best possible results for the specific patient is a main factor for the success in IVF or ICSI. The response of many patients to the ovarian stimulation used is very poor, giving fewer oocytes than expected, resulting in much lower, if any, pregnancy rates. The definition of a poor responder is not clear and differs among researchers. A variety of strategies have been used to improve response in these patients, regardless of the definition used. These include various ovulation induction protocols that we believe might assist these patients achieve a pregnancy. The difficulty is greater due to the fact that poor responders are not a homogeneous group and each patient may have a different cause. More studies with large numbers of patients are needed in order to find those protocols that could provide these couples with an acceptable pregnancy rate.

Increasing the gonadotrophin dose in the course of an in vitro fertilization cycle does not rectify an initial poor response

OBJECTIVE

To evaluate the value of increasing the gonadotrophin dose after 5 days of controlled ovarian stimulation in IVF patients who show an initial poor response to stimulation.

SUBJECTS AND METHODS

We identified all IVF cycles between January 1992 and March 1996 in which ovarian response after 5 days of controlled ovarian hyperstimulation (COH) with 225-300 IU per day of human menopausal gonadotrophins (hMG; Metrodin or Pergonal) was monitored by measurement of serum estradiol concentrations (n=596 patients). According to estradiol concentration, the daily dose of hMG was doubled or increased to 450 IU in 193 patients (group A) or maintained the same in 403 patients (group B). Further cycle monitoring was achieved using serial ultrasound and serum estradiol measurements.

RESULTS

The two groups were age-matched. Group A patients experienced a higher cancellation rate despite having a higher mean number of hMG ampoules (59.5 versus 36.2) and a longer duration of stimulation (12.2 versus 10.8 days). They achieved lower levels of serum estradiol on days 9 and 10 of stimulation, produced a lower mean number of oocytes per retrieval (5.8 versus 8.9) and had a lower clinical pregnancy rate per cycle (8.3 versus 23.4%) compared to group B. All differences were statistically significant.

CONCLUSION

The poor outcome of cycles with initial low response to COH appears not to be averted by doubling or increasing the hMG dose after 5 days of stimulation.

Poor responders: does the protocol make a difference?

An inadequate response to gonadotropins during in-vitro fertilization treatment may result in cycle cancellation, fewer embryos available for transfer and decreased pregnancy rates. For these reasons, numerous strategies to improve ovarian stimulation in poor responders have been proposed. These include variations in the type, dose and timing of gonadotropins, gonadotropin-releasing hormone agonists and gonadotropin-releasing hormone antagonists. Unfortunately, despite optimism generated by studies using retrospective controls, epidemiologically sound trials have been scarce. Indeed, of the three prospective randomized trials performed in poor responders to date no compelling advantage for one stimulation protocol over another has been established. Although this lack of improvement may reflect inadequate sample sizes, an alternative explanation is simply that the protocol, after a certain point, does not make a difference. Aside from oocyte donation, greater hope for poor responders may rest in aneuploidy screening, in-vitro oocyte maturation and cytoplasm/nuclear transfer.

Evaluating strategies for improving ovarian response of the poor responder undergoing assisted reproductive techniques

OBJECTIVE

To assess the efficacy of various controlled ovarian hyperstimulation (COH) regimens in the prior poor-responder patient preparing for assisted reproductive techniques.

DESIGN

English-language literature review.

PATIENT(S)

Candidates for assisted reproductive techniques who had been defined as having a prior suboptimal response to standard COH regimens.

INTERVENTION(S)

A variety of regimes are reviewed, including increased gonadotropin doses, change of gonadotropins, adjunctive growth hormone (GH), luteal phase (long) GnRH agonist (GnRH-a) initiation, early follicular phase (flare) GnRH-a initiation, low-dose luteal phase (ultrashort) GnRH-a initiation, progestin pretreatment, and microdose flare GnRH-a initiation.

MAIN OUTCOME MEASURE(S)

Maximal serum E(2) levels, follicular development, dose, and duration of gonadotropin therapy, cycle cancellation rates, oocytes retrieved, embryos transferred, and clinical and ongoing pregnancy rates.

RESULT(S)

A lack of uniformity in definition of the poor responder and of prospective randomized trials make data interpretation somewhat difficult. Of the varied strategies proposed, those that seem to be more uniformly beneficial are microdose GnRH-a flare and late luteal phase initiation of a short course of low-dose GnRH-a discontinued before COH.

CONCLUSION(S)

No single regimen will benefit all poor responders. General acceptance of uniform definitions and performance of large-scale prospective randomized trials are critical. Development of a reliable precycle screen will allow effective differentiation among normal responders, poor responders, and those who will not conceive with their own oocytes.

The prognostic importance of the number of oocytes retrieved and estradiol levels in poor and normal responders in in vitro fertilization (IVF) treatment

A low response to ovarian stimulation in in vitro fertilization poses a unique therapeutic challenge. Gonadotropin-releasing hormone agonists (GnRHa) have been suggested as a modality for treatment of this condition. In this study, we analyzed the results of 880 in vitro fertilization treatment cycles with respect to modality of ovarian stimulation, degree of hormonal response, and number of oocytes retrieved. In patients with estradiol (E2) levels less than 501 pg/ml on the day of human chorionic gonadotropin administration, 27% pregnancy rate was achieved with clomiphene citrate (CC) combined with human menopausal gonadotropin (hMG), compared to 15.1% (P less than 0.005) with hMG alone and 20.8% (NS) with GnRHa and hMG. Pregnancy rates were not lower in these patients compared to patients with higher estradiol levels in the different stimulation protocols, but pregnancy rates were significantly lower in cycles during which three or fewer oocytes were retrieved, compared to those in which four or more oocytes were retrieved (10.8 vs 23.8%; P less than 0.0005). In low-retrieval cycles pregnancy rates actually decreased with increasing levels of estradiol. Our results indicate that the number of oocytes retrieved is a better prognostic parameter than E2 levels in predicting the outcome of in vitro fertilization treatment and that GnRHa in the long protocol do not seem to be superior to CC combined with hMG for the treatment of poor responders.