The clinical significance of the retrieval of a low number of oocytes following mild ovarian stimulation for IVF: a meta-analysis

Ovarian stimulation protocols in assisted reproductive technology: an update

Controlled ovarian stimulation (COS) with gonadotropins to produce multiple follicular development and high-quality oocytes is the cornerstone of assisted reproductive technology. Today, recombinant human follicle-stimulating hormone (r-hFSH) is widely used for COS. A long-acting r-hFSH and a combination of r-hFSH and recombinant human luteinizing hormone have recently become available. Formulations of purified urinary FSH with or without luteinizing hormone activity (provided by human chorionic gonadotropin) are also available. COS protocols can now be individualized to optimize efficacy and safety - defined as singleton pregnancies with a low incidence of ovarian hyperstimulation syndrome. This is facilitated by an estimation of ovarian response using the antral follicle count and/or serum anti-Müllerian hormone levels; anti-Müllerian hormone is viewed as the most reliable single marker. However, an efficient management strategy for poor responders to COS is still required. Developments in biomarkers and other techniques for accurate identification of viable oocytes and embryos and optimal uterine receptivity are expected.

Gonadotropin therapy: a 20th century relic

Gonadotropin therapy has been a cornerstone of infertility therapy for half a century. From the very beginning, its use has been associated with a high rate of multiple births, particularly high order multiples, and ovarian hyperstimulation syndrome. Initially, success rates seemed acceptable when used for superovulation (SO)/IUI therapy. However, as data from RCTs have emerged, reported outcomes suggest that we question the use of injectible gonadotropins. This manuscript examines the studies that have challenged gonadotropin use for SO/IUI and other research that supports reduced doses of gonadotropins for IVF. We examine the challenges for its continued use for SO/IUI and for moving to lower doses worldwide for IVF. We propose a future that views gonadotropins as a relic of the twentieth century.

Increasing the Stimulation Dose of rFSH in Unexpected Poor Responders Is Not Associated with Better IVF Outcome

The aim of this retrospective study is to determine whether increasing the stimulation dose of rFSH in unexpected poor responders is associated with better in vitro fertilization (IVF) outcome or not. A total of forty eligible women who fulfilled our definition of poor responders and who did not achieve an ongoing pregnancy in the first cycle and returned for a second higher rFSH dose IVF cycle with a long-agonist protocol were included to the study. The first low-dose cycles and the second high-dose cycles were compared to each other. Main outcome measures of the study were duration of stimulation, number of follicles, number of oocytes retrieved, number of embryos, and E2 level on day of hCG injection. There were no significant differences in duration of stimulation, number of follicles, number of oocytes retrieved, number of embryos, and E2 level on day of hCG injection between the first low- and second high-dose cycles. Daily dose and total dose of rFSH were significantly higher in the second high-dose cycles. Increasing the dose of rFSH in a second stimulation cycle after first unsuccessful treatment cycle will add only to the cost and discomfort of the treatment and might adversely affect pregnancy rates.

The poor responder in IVF: is the prognosis always poor?: a systematic review

BACKGROUND In IVF treatment a considerable proportion of women are faced with a low number of oocytes retrieved. These poor responders have reduced pregnancy rates compared with normal responders. However, this may not be applicable to all poor responders. This review aims at identifying patient characteristics and ovarian reserve tests (ORT) that will determine prognosis for pregnancy in poor responders. METHODS A systematic search was conducted in PubMed, Embase, Cochrane and SCOPUS databases in April 2010. Studies regarding patient characteristics or ORT in poor responders and their pregnancy prospects were included. All included papers were summarized in descriptive tables. RESULTS Nineteen studies were included. Pooled data of six studies comparing poor and normal responders demonstrated clearly lower pregnancy rates in poor responders (14.8 versus 34.5%). Ten studies indicated that older poor responders have a lower range of pregnancy rates compared with younger (1.5-12.7 versus 13.0-35%, respectively). Four studies showed that pregnancy prospects become reduced when fewer oocytes are retrieved (0-7% with 1 oocyte versus 11.5-18.6% with 4 oocytes). Five studies concerning pregnancy rates in subsequent cycles suggested a more favourable outcome in unexpected poor responders, and if ≥2 oocytes were retrieved. CONCLUSIONS Poor responders are not a homogeneous group of women with regards to pregnancy prospects. Female age and number of oocytes retrieved in particular will modulate the chances for pregnancy in current and subsequent cycles. Applying these criteria will allow the identification of couples with a reasonable prognosis and balanced decision-making on the management of poor responders.

[Use of GnRH antagonist for in vitro fertilization]

BACKGROUND

For many patients, the typical treatment protocol for in vitro fertilization (IVF) is both physically and psychologically demanding. An alternative approach to use of gonadotropin-releasing hormone (GnRH)-agonists traditionally used to prevent premature ovulation, is use of GnRH-antagonists. The aim of this article is to describe advantages and disadvantages of using GnRH-antagonists in IVF.

MATERIAL AND METHODS

The paper is based on literature identified through a non-systematic search in PubMed, and more than ten years of clinical experience with use of GnRH antagonists in IVF.

RESULTS

To maintain a similar pregnancy rate as that with GnRH-agonists, one can use GnRH-antagonists at an earlier time-point during stimulation of the ovaries and a lower dose of follicle stimulating hormone (FSH). A less intensive stimulation implies a lower risk of complications and side effects and a shorter treatment period before egg collection (from four-five weeks to less than two weeks). The main disadvantage of the GnRH-antagonist protocol is that ovarian stimulation cannot be programmed to the same extent as that with use of a GnRH-agonist.

INTERPRETATION

Stimulation with a GnRH-antagonist instead of a GnRH-agonist in IVF, is less physically and psychologically demanding for the patients and maintains the same birth rate.

How many eggs are needed to produce an assisted reproductive technology baby: is more always better?

OBJECTIVE

To evaluate the association between the number of mature (metaphase II [MII]) oocytes per assisted reproductive technology (ART) cycle and the likelihood of live birth.

DESIGN

Retrospective study.

SETTING

Academic infertility practice.

PATIENT(S)

Seven hundred thirty-seven infertile women undergoing their initial fresh embryo, nondonor IVF or intracytoplasmic sperm injection cycle at Montefiore's Institute for Reproductive Medicine and Health between January 2002 and December 2008.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Live birth.

RESULT(S)

Two hundred twenty-four cycles resulted in a live birth (30.4%). Live birth cycles had significantly more MII oocytes obtained per cycle as compared with their unsuccessful counterparts (11.0 ± 5.9 vs. 9.7 ± 6.2, respectively). Multivariate logistic regression was done to determine the minimum number of MII oocytes per cycle as a predictor of live birth after adjustment for age and historical maximum FSH values. Cycles that included the average number of MII in this cohort were used as a reference group. For cycles with five or fewer MII oocytes obtained, there was a statistically significant decrease in the likelihood of a live birth as compared with the reference group (odds ratio 0.61, 95% confidence interval 0.38-0.99). However, cycles with six or fewer obtained MII oocytes were not less likely to result in a live birth when compared with the reference group (odds ratio 0.69, 95% confidence interval 0.45-1.08).

CONCLUSION(S)

In our cohort, there was an advantage to obtaining six or more MII oocytes during the fresh oocyte retrieval compared with five or fewer oocytes. There was not an advantage, however, to obtaining 10 or more or 15 or more oocytes as compared with obtaining 6-9 oocytes. The strategy of aiming for a greater number of oocytes in an ART cycle should be revisited.

Individualised controlled ovarian stimulation (iCOS): maximising success rates for assisted reproductive technology patients

BACKGROUND

In the last two decades, pregnancy rates for patients undergoing in-vitro fertilisation (IVF) have significantly increased. Some of the major advances responsible for this improvement were the introduction of controlled ovarian stimulation (COS) for the induction of multiple follicle development, and the utilisation of mid-luteal gonadotropin-releasing hormone agonists to achieve pituitary down-regulation and full control of the cycle. As a result, a combination of a gonadotropin-releasing hormone agonist with high doses (150-450 IU/day) of recombinant follicle-stimulating hormone has become the current standard approach for ovarian stimulation. However, given the heterogeneity of patients embarking on IVF, and the fact that many different drugs can be used alone or in different combinations (generating multiple potential protocols of controlled ovarian stimulation), we consider the need to identify special populations of patients and adapt treatment protocols accordingly, and to implement a more individualised approach to COS.

DISCUSSION

Studies on mild, minimal and natural IVF cycles have yielded promising results, but have focused on fresh embryo transfers and included relatively young patient populations who generally have the potential for more favourable outcomes. The efficacy of these protocols in patients with a poorer prognosis remains to be tested. When comparing protocols for COS, it is important to think beyond current primary endpoints, and to consider the ideal quality and quantity of oocytes and embryos being produced per stimulated patient, in order to achieve a pregnancy. We should also focus on the cumulative pregnancy rate, which is based on outcomes from fresh and frozen embryos from the same cycle of stimulation. Individualised COS (iCOS) determined by the use of biomarkers to test ovarian reserve has the potential to optimise outcomes and reduce safety issues by adapting treatment protocols according to each patient's specific characteristics. As new objective endocrine, paracrine, functional and/or genetic biomarkers of response are developed, iCOS can be refined further still, and this will be a significant step towards a personalised approach for IVF.

CONCLUSIONS

A variety of COS protocols have been adopted, with mixed success, but no single approach is appropriate for all patients within a given population. We suggest that treatment protocols should be adapted for individual patients through iCOS; this approach promises to be one of the first steps towards implementing personalised medicine in reproductive science.

Multiplying recipients paired with oocyte donors optimizes the use of donated oocytes

OBJECTIVE

To review donor-egg assisted reproductive technology (ART) activity using young fertile donors (<37 years of age) paired with multiple recipients.

DESIGN

Age-matched cohort study.

SETTING

Tertiary ART center at Cochin Hospital, Paris.

PATIENT(S)

A total of 125 oocyte donors and 361 age-matched control subjects. Donated oocytes were attributed to 163 different recipients undertaking 258 transfer cycles.

INTERVENTION(S)

Donor-egg and regular ART.

MAIN OUTCOME MEASURE(S)

Controlled ovarian hyperstimulation (COH) outcome-oocytes provided-was compared in donors and control subjects. Clinical pregnancy (cPR), ongoing pregnancy (oPR), and implantation (IR) rates per transfer in recipients were compared with age-matched controls. IRs were analyzed in the various recipients as a function of the number of oocytes harvested.

RESULT(S)

COH outcome was similar in donors and control subjects. cPR (37.5%), oPR (28.4%), and IR (24.4%) were slightly but significantly lower in donor-egg recipients compared with control subjects (44.9%, 37.4%, and 31.8%, respectively). More embryos (average +2.06) were transferred fresh and fewer frozen. In recipients, IRs were independent from the number of oocytes received in the donor.

CONCLUSION(S)

Multiplying recipients paired with oocyte donors slightly lowered per-transfer outcome, but enabled more (average +2.06) embryos to be transferred fresh.

Anti-Mullerian hormone is a better marker than inhibin B, follicle stimulating hormone, estradiol or antral follicle count in predicting the outcome of in vitro fertilization

OBJECTIVE

The present study aims to compare anti-Mullerian hormone (AMH) with other ovarian reserve markers and to find a cut-off value of AMH for predicting ovarian response towards controlled ovarian hyperstimulation in an in vitro fertilization (IVF) program.

MATERIALS AND METHODS

A prospective analysis was performed in 180 patients undergoing their first IVF trial, which is being conducted at a department of assisted reproduction in a tertiary medical center. The main outcome measures were determined as age and antral follicle count as well as the serum concentrations of follicle stimulating hormone, luteinizing hormone (LH), estradiol (E2), inhibin B and AMH. The predictive power of the aforementioned measures in specifying ovarian response was determined by means of discriminate analyses.

RESULTS

As expected, day 3 LH levels were significantly high in the poor responder group. The poor responders had significantly lower antral follicle counts, retrieved oocyte number, and mature oocyte counts as well as day 3 AMH levels (5.8 ± 2.32 vs. 1.8 ± 0.80 ng/ml). There was a positive correlation with antral follicle count, basal AMH, E2 and follicle count on the day of HCG administration and negative correlation with age. The AMH level was addressed as the only significant factor in determination of mature oocyte number. A cut-off point for serum AMH concentration indicating the value of 2.97 ng/ml was found to predict the poor ovarian response with a sensitivity of 100.0% and a specificity of 89.6%. However, the same cut-off point was not as predictive for the non-conception circumstance.

CONCLUSION

The present study concludes that AMH is a promising biochemical marker for the prediction of ovarian response and that a cut-off point indicating the value of 2.97 ng/ml can be adopted for this prediction.

Milder is better? Advantages and disadvantages of "mild" ovarian stimulation for human in vitro fertilization

In the last decades, several steps have been made aiming at rendering human IVF more successful on one side, more tolerable on the other side. The "mild" ovarian stimulation approach, in which a lower-than-average dose of exogenous gonadotropins is given and gonadotropin treatment is started from day 2 to 7 of the cycle, represents a significant step toward a more patient's friendly IVF. However, a clear view of its virtues and defects is still lacking, because only a few prospective randomized trials comparing "mild" vs. conventional stimulation exist, and they do not consider some important aspects, such as, e.g., thawing cycles. This review gives a complete panorama of the "mild" stimulation philosophy, showing its advantages vs. conventional ovarian stimulation, but also discussing its disadvantages. Both patients with a normal ovarian responsiveness to exogenous gonadotropins and women with a poor ovarian reserve are considered. Overall, we conclude that the level of evidence supporting the use of "mild" stimulation protocols is still rather poor, and further, properly powered prospective studies about "mild" treatment regimens are required.

Oocyte yield and dysmorphisms as indicators of biological efficiency in intracytoplasmic sperm injection cycles

The aim of the study was to examine whether oocyte yield could be an indicator of morphological oocyte quality and biological competency in patients younger than 36 years undergoing controlled ovarian stimulation (COS). Three hundred and thirty-five intracytoplasmic sperm injection (ICSI) procedures were arbitrarily subdivided into five groups according to the number of retrieved oocytes. Patients' demographic characteristics and treatment success were compared among the groups. The influence of the morphological oocyte abnormalities on outcomes was also investigated. The proportion of oocytes that gave rise to viable embryos and high-quality embryos decreased significantly according to oocyte yield. Similarly, the number of foetal heartbeat per retrieved oocyte in fresh embryo transfer cycles was higher in patients with fewer oocytes collected. Finally, a negative correlation was observed between the occurrence of intracytoplasmic oocyte dysmorphisms and the number of foetal heartbeat per oocyte. High oocyte yield may be considered an indicator of low oocyte biological efficiency and intracytoplasmic dysmorphisms may contribute to this biological wastage suggesting that protocols of minimal or mild stimulation should be used.

Risk charts to identify low and excessive responders among first-cycle IVF/ICSI standard patients

Ovarian stimulation carries a risk of either low or excessive ovarian response. The aim was to develop prognostic models for identification of standard (ovulatory and normal basal FSH) patients’ risks of low and excessive response to conventional stimulation for IVF/intracytoplasmic sperm injection. Prospectively collected data on 276 first-cycle patients treated with 150 IU recombinant FSH (rFSH)/day in a long agonist protocol were analysed. Logistic regression analysis was applied to the outcome variables:low (seven or less follicles) and excessive (20 or more follicles) response. Variables were woman’s age, menstrual cycle length, weight or body mass index, ovarian volume, antral follicle count (AFC) and basal FSH. The predictive performance of the models was evaluated from the prediction error (Brier score, %) where zero corresponds to a perfect prediction. Model stability was assessed using 1000 bootstrap cross-validation steps. The best prognostic model to predict low response included AFC and age (Brier score 7.94) and the best model to predict excessive response included AFC and cycle length (Brier score 15.82). Charts were developed to identify risks of low and excessive ovarian response. They can be used for evidence-based risk assessment before ovarian stimulation and may assist clinicians in individual dosage of their patients.

A randomised controlled trial of 300 versus 225 IU recombinant FSH for ovarian stimulation in predicted normal responders by antral follicle count

OBJECTIVE

To test the hypothesis that among women predicted to have a normal ovarian response, ovarian stimulation using 300 IU follicle-stimulating hormone (FSH) results in the retrieval of more mature oocytes than 225 IU during in vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI) treatment.

DESIGN

Prospective randomised controlled study.

SETTING

University-based assisted conception unit.

POPULATION

A cohort of 131 women predicted to have a normal ovarian response to gonadotrophin stimulation, based on antral follicle count.

METHODS

Subjects undergoing their first cycle of IVF/ICSI were randomised to receive a fixed daily dose of 300 (experimental arm) or 225 IU (control arm) of recombinant FSH (Gonal-F).

MAIN OUTCOME MEASURES

Number of mature oocytes retrieved and live birth rates.

RESULTS

The number (mean +/- standard deviation) of mature oocytes retrieved (8.2 +/- 5.0 versus 9.0 +/- 4.8, for 300 and 225 IU, respectively; P = 0.34) was similar in each group. There were no differences between the 300- and 225 IU arms in live birth rates (31 versus 41%, respectively; P = 0.25), cycle cancellations resulting from insufficient ovarian response (0 versus 6.1%, respectively; P = 0.12), and prevalence of moderate (3.1 versus 3.0, respectively; P = 1.0) and severe (0 versus 1.5%, respectively; P = 1.0) ovarian hyperstimulation syndrome.

CONCLUSIONS

The use of a higher daily dose of 300 IU of recombinant FSH for ovarian stimulation does not improve the number of mature oocytes retrieved, or live birth rates, among women with a predicted normal response during conventional IVF/ICSI.

Approaches to improve the diagnosis and management of infertility

BACKGROUND Recent advances in our understanding of the causes of infertility and of assisted reproductive technology (ART) have led to the development of complex diagnostic tools, prognostic models and treatment options. The Third Evian Annual Reproduction (EVAR) Workshop Meeting was held on 26-27 April 2008 to evaluate evidence supporting current approaches to the diagnosis and management of infertility and to identify areas for future research efforts. METHODS Specialist reproductive medicine clinicians and scientists delivered presentations based on published literature and ongoing research on patient work-up, ovarian stimulation and embryo quality assessment during ART. This report is based on the expert presentations and subsequent group discussions and was supplemented with publications from literature searches and the authors' knowledge. RESULTS It was agreed that single embryo transfer (SET) should be used with increasing frequency in cycles of ART. Continued improvements in cryopreservation techniques, which improve pregnancy rates using supernumerary frozen embryos, are expected to augment the global uptake of SET. Adaptation and personalization of fertility therapy may help to optimize efficacy and safety outcomes for individual patients. Prognostic modelling and personalized management strategies based on individual patient characteristics may prove to represent real progress towards improved treatment. However, at present, there is limited good-quality evidence to support the use of these individualized approaches. CONCLUSIONS Greater quality control and standardization of clinical and laboratory evaluations are required to optimize ART practices and improve individual patient outcomes. Well-designed, good-quality studies are required to drive improvements to the diagnosis and management of ART processes.

Fewer medications for in vitro fertilization can be better: thinking outside the box

Minimal stimulation or mild stimulation protocols for in vitro fertilization offer many advantages for all patients, but especially for low and high responders. In the current practice of reducing the number of embryos transferred to a maximum of two for a significant number of patients, using aggressive and high-dose gonadotropins to obtain a large, and sometimes excessive, number of oocytes should be questioned.

Mild ovarian stimulation for IVF

BACKGROUND

Mild ovarian stimulation for in vitro fertilization (IVF) aims to achieve cost-effective, patient-friendly regimens which optimize the balance between outcomes and risks of treatment.

METHODS

Pubmed and Medline were searched up to end of January 2008 for papers on ovarian stimulation protocols for IVF. Additionally, references to related studies were selected wherever possible.

RESULTS

Studies show that mild interference with the decrease in follicle-stimulating hormone levels in the mid-follicular phase was sufficient to override the selection of a single dominant follicle. Gonadotrophin-releasing hormone antagonists compared with agonists reduce length and dosage of gonadotrophin treatment without a significant reduction in the probability of live birth (OR 0.86, 95% CI 0.72-1.02). Mild ovarian stimulation may be achieved with limited gonadotrophins or with alternatives such as anti-estrogens or aromatase inhibitors. Another option is luteinizing hormone or human chorionic gonadotrophin administration during the late follicular phase. Studies regarding these approaches are discussed individually; small sample size of single studies along with heterogeneity in patient inclusion criteria as well as outcomes analysed does not allow a meta-analysis to be performed. Additionally, the implications of mild ovarian stimulation for embryo quality, endometrial receptivity, cost and the psychological impact of IVF treatment are discussed.

CONCLUSIONS

Evidence in favour of mild ovarian stimulation for IVF is accumulating in recent literature. However, further, sufficiently powered prospective studies applying novel mild treatment regimens are required and structured reporting of the incidence and severity of complications, the number of treatment days, medication used, cost, patient discomfort and number of patient drop-outs in studies on IVF is encouraged.