hMG increases the yield of mature oocytes and excellent-quality embryos in patients with a previous cycle having a high incidence of oocyte immaturity
2009; Elsevier BV; Volume: 92; Issue: 3 Linguagem: Inglês
10.1016/j.fertnstert.2009.02.039
ISSN1556-5653
AutoresHeather G. Huddleston, Katharine V. Jackson, Joseph Doyle, Catherine Racowsky,
Tópico(s)Reproductive System and Pregnancy
ResumoIn a selected group of patients with >20% oocyte immaturity during an IVF cycle with FSH alone, the addition of hMG to the stimulation protocol results in a higher yield of mature oocytes and excellent-quality embryos. In a selected group of patients with >20% oocyte immaturity during an IVF cycle with FSH alone, the addition of hMG to the stimulation protocol results in a higher yield of mature oocytes and excellent-quality embryos. In the natural cycle, both LH and FSH appear to play a role in the maturation of the oocyte (1Hillier S.G. Gonadotropic control of ovarian follicular growth and development.Mol Cell Endocrinol. 2001; 179: 39-46Crossref PubMed Scopus (287) Google Scholar). However, in the setting of exogenous stimulation with gonadotropins, both with and without down-regulation, the precise requirements of FSH and, in particular, LH for adequate development and maturation of the ovarian follicle remain a debated issue (2Fischer R. Understanding the role of LH: myths and facts.Reprod Biomed Online. 2007; 15: 468-477Abstract Full Text PDF PubMed Scopus (22) Google Scholar). With the growing availability of highly purified and recombinant forms of both gonadotropins, this question has become increasingly pertinent. Whereas some investigators suggest that patients undergoing GnRH down-regulation may have profoundly suppressed endogenous LH levels and therefore may achieve suboptimal outcomes when stimulated with FSH alone (3Westergaard L.G. Laursen S.B. Andersen C.Y. Increased risk of early pregnancy loss by profound suppression of luteinizing hormone during ovarian stimulation in normogonadotrophic women undergoing assisted reproduction.Hum Reprod. 2000; 15: 1003-1008Crossref PubMed Scopus (259) Google Scholar, 4Esposito M.A. T. Barnhart K. Coutifaris P. Patrizio C. Role of periovulatory luteinizing hormone concentrations during assisted reproductive technology cycles stimulated exclusively with recombinant follicle-stimulating hormone.Fertil Steril. 2001; 75: 519-524Abstract Full Text Full Text PDF PubMed Scopus (84) Google Scholar), others have argued that LH supplementation in this setting does not improve implantation rates and may even be detrimental to secondary outcomes such as oocyte and embryo yield (5Balasch J. Penarrubia J. Fabregues F. Vidal E. Casamitjana R. Mana D. et al.Ovarian responses to recombinant FSH or hMG in normogonadotrophic women following pituitary desensitization by a depot GnRH agonist for assisted reproduction.Reprod Biomed Online. 2003; 7: 35-42Abstract Full Text PDF PubMed Scopus (52) Google Scholar, 6Fabregues F. Creus M. Penarrubia J. Manau D. Vanrell J.A. Balasc J. et al.Effects of recombinant human luteinizing hormone supplementation on ovarian stimulation and the implantation rate in down-regulated women of advanced reproductive age.Fertil Steril. 2006; 85: 925-931Abstract Full Text Full Text PDF PubMed Scopus (55) Google Scholar). Recent large controlled trials have suggested that cycles supplemented with an LH-containing product have statistically equivalent outcomes compared with cycles stimulated with FSH alone (7N. Andersen A. Devroey P. Arce J.C. Clinical outcome following stimulation with highly purified hMG or recombinant FSH in patients undergoing IVF: a randomized assessor-blind controlled trial.Hum Reprod. 2006; 21: 3217-3227Crossref PubMed Scopus (248) Google Scholar, 8Marrs R. Meldrum D. Muasher S. Schoolcraft W. Werlin L. Kell E. et al.Randomized trial to compare the effect of recombinant human FSH (follitropin alfa) with or without recombinant human LH in women undergoing assisted reproduction treatment.Reprod Biomed Online. 2004; 8: 175-182Abstract Full Text PDF PubMed Scopus (139) Google Scholar, 9Nyboeandersen A. Humaidan P. Fried G. Hausken J. Antila L. Bangsboll S. et al.Recombinant LH supplementation to recombinant FSH during the final days of controlled ovarian stimulation for in vitro fertilization. A multicentre, prospective, randomized, controlled trial.Hum Reprod. 2008; 23: 427-434Crossref PubMed Scopus (52) Google Scholar). Nevertheless, debate continues regarding which specific subgroups may or may not benefit from LH supplementation. For example, Marrs et al. (8Marrs R. Meldrum D. Muasher S. Schoolcraft W. Werlin L. Kell E. et al.Randomized trial to compare the effect of recombinant human FSH (follitropin alfa) with or without recombinant human LH in women undergoing assisted reproduction treatment.Reprod Biomed Online. 2004; 8: 175-182Abstract Full Text PDF PubMed Scopus (139) Google Scholar), in a subgroup analysis of a larger trial, suggested that older women (>35 years) may derive specific benefit from LH supplementation. In contrast, Chung et al. (10Chung K. Krey L. Katz J. Noyes N. Evaluating the role of exogenous luteinizing hormone in poor responders undergoing in vitro fertilization with gonadotropin-releasing hormone antagonists.Fertil Steril. 2005; 84: 313-318Abstract Full Text Full Text PDF PubMed Scopus (29) Google Scholar) reported in a retrospective study that patients ≥40 years old stimulated with recombinant FSH and hMG produced fewer oocytes and embryos than those stimulated with FSH alone, a finding not seen in patients 20% oocyte immaturity (FSH cycles) and who then underwent a subsequent cycle using the same stimulation protocol as used in the first cycle (microflare, antagonist, or low-dose long luteal). Two patient cohorts were developed that were distinguished by their use of hMG in the second cycle: Those in cohort 1 used hMG in addition to FSH in their second cycle (FSH/hMG cycles; n = 110 pairs), and those in cohort 2 (the control group) used only FSH in their second cycle (n = 62). For patients in cohort 1, hMG was most frequently given in a 1:1 ratio with pure FSH. Cycle pairs were excluded if they were discordant for intracytoplasmic sperm injection (ICSI)/non-ICSI. Oocyte maturity was assessed after removal of the cumulus cells before injection in cases of ICSI or at the fertilization check in cases of standard IVF insemination. Oocytes were classified as immature if they exhibited either a germinal vesicle or a smooth homogeneous cytoplasm with no evidence of an extruded polar body. Cycle characteristics and outcomes were compared between the first and second cycle for each pair. Excellent-quality embryos were defined as having at least eight cells with <10% fragmentation on day 3, 68–72 hours after insemination. For cohort 1 cycles, four analyses were performed to compare: 1) pairs regardless of absolute amount of FSH used; 2) pairs in which the starting FSH dose increased in the second cycle (n = 43); 3) pairs in which the FSH dose was the same in the first and second cycles (n = 43); and 4) pairs in which the starting FSH dose decreased in the second cycle (n = 24). The absolute amount of FSH administered to each patient was determined by adding the total amount of FSH present in both the FSH and the hMG ampules. Wilcoxon rank sum test for matched pairs was used for all analyses, with P<.05 considered to be statistically significant. The results of the analysis of cohort 1 revealed that the patients in the FSH alone group were slightly younger than in the FSH/hMG group (35.1 ± 3.85 yrs vs. 35.5 ± 3.83 yrs; P<.0001; Table 1). More than one-half of the study cohort (60%) used ICSI or split ICSI, and 40% used standard IVF insemination. The dose of hMG administered in the hMG group ranged from 1 to 4 ampules per day, with a mean of 2.7 ampules. The distributions of patients according to stimulation protocols were: 86% long luteal, 10% microflare, and 4% antagonist. Results according to cycle parameters and oocytes retrieved are shown in Table 1. There was no difference between the FSH and the FSH/hMG groups for number of days of stimulation, total ampules of gonadotropin used, or timing of hCG trigger as assessed by number of follicles >16 mm or 17 mm at time of hCG or by the mean diameter of the two lead follicles. Although the total number of oocytes retrieved did not differ between groups, there were significantly more mature eggs retrieved in the FSH/hMG cycles (11.2 ± 6.6 vs. 9.4 ± 5.2; P<.0001) and significantly more embryos of excellent morphologic grade obtained (1.4 ± 2.4 vs. 0.90 ± 1.5; P=.028) compared with the FSH cycles.Table 1Cycle characteristics and outcomes (cohort 1).FSH cyclesFSH/hMG cyclesP valueAnalysis 1: all cycles (n =110) Peak E2 (pg/mL)1,842 ± 8452,229 ± 970NS No. of follicles at hCG trigger12.9 ± 5.013.7 ± 6.3NS No. of follicles >17 mm at hCG3.1 ± 1.63.1 ± 1.6NS No. of follicles >16 mm at hCG4.5 ± 2.14.4 ± 2.2NS Diameter of 2 lead follicles19.8 ± 1.519.3 ± 3.0NS No. of ampules48.3 ± 20.249.9 ± 22.3NS No. of oocytes14.9 ± 7.215.6 ± 7.9NS No. of immature oocytes5.5 ± 3.24.3 ± 3.7.0009 % immature oocytes37.3 ± 11.827.0 ± 17.0<.0001 No. of mature oocytes9.4 ± 5.211.2 ± 6.6.001 % mature oocytes64 ± 1273 ± 18<.0001 No. of fertilized oocytes6.3 ± 4.17.4 ± 5.4.08 No. of excellent-quality embryos0.9 ± 1.51.4 ± 2.4.028Analysis 2: dose increased in second cycle (n =43) No. of mature oocytes7.5 ± 3.111.0 ± 5.5.0002 % mature oocytes62.8 ± 10.671.4 ± 16.5.005Analysis 3: dose same in second cycle (n =43) No. of mature oocytes8.7 ± 4.110.9 ± 6.6.005 % mature oocytes63.5 ± 13.273.3 ± 19.1.001Analysis 4: dose decreased in second cycle (n =24) No. of mature oocytes14.5 ± 6.413.0 ± 7.6.3 % mature oocytes64.0 ± 11.372.0 ± 16.6.05 Open table in a new tab To determine if our observation of an increased yield of mature oocytes in the FSH/hMG cycles was independent of the starting daily dose of FSH used in the second cycle, we reanalyzed the data after stratifying the cycle pairs according to whether the starting FSH dose had increased, stayed the same, or decreased in the second cycle. For patients in whom the overall starting daily dose of FSH was either increased or stayed the same, there was a significant increase in both the number and the percentage of mature eggs in the hMG-supplemented cycle. In contrast, for those patients in whom the FSH dose was decreased in the second cycle, the total number of mature eggs did not change, but the percentage of mature eggs was still higher in the hMG-supplemented group. We also examined the role of stimulation protocol. Although the number of patients stimulated with a microflare (n = 9) or antagonist (n = 11) protocol was too small for meaningful stratification, analysis of only patients completing a long luteal protocol (n = 90) did not significantly change the results. Long luteal cycles using hMG demonstrated a higher proportion of mature oocytes (73.2% vs 62.5%; P=.0001) and a trend toward more excellent-quality embryos (1.48 vs. 0.99; P=.08). Analysis of cohort 2 (the control group) also demonstrated that patients in their first FSH only cycle were younger than in their subsequent FSH only cycle (35.4 ± 4.1 yrs vs. 35.8 ± 4.0 yrs; P<.0001). The majority of patients were stimulated with a low-dose long luteal protocol (93.5%), with the remainder stimulated with microflare (6.5%). As with cohort 1, there was no difference between the cycle pairs regarding days of stimulation, number of follicles, peak E2, and total ampules of FSH used across the two cycles. In contrast to cohort 1, however, there was no difference in maturity observed between the first FSH only cycle and the subsequent FSH only cycle (% metaphase II [MII]: 64.2 ± 9.4% vs. 63.3 ± 11.5%; no. MII: 11.0 ± 4.8 vs. 10.9 ± 5.3). There was also no difference in the number of eight-cell embryos (2.1 ± 1.7 vs. 2.2 ± 2.0) or in number of top-quality embryos (2.2 ± 1.9 vs. 2.0 ± 2.2) noted between the first and second cycles. In the context of controlled ovarian stimulation for IVF, the precise requirements of FSH and, in particular, LH for adequate development and maturation of the ovarian follicle remain unclear. In the patient with hypogonadotropic hypogonadism, LH supplementation is required to achieve appropriate growth and maturation of the oocyte (12Balasch J. Burzaco I. Casamitjana R. Civico Ballesca J.L. The role of luteinizing hormone in human follicle development and oocyte fertility: evidence from in-vitro fertilization in a woman with long-standing hypogonadotrophic hypogonadism and using recombinant human follicle stimulating hormone.Hum Reprod Suppl. 1995; 10: 1678-1683Crossref PubMed Scopus (139) Google Scholar). However, although it is accepted that some LH is necessary for the formation of a developmentally competent oocyte and subsequent establishment of pregnancy, the precise threshold is not known. When down-regulated with GnRH agonists, pituitary suppression is achieved and LH exists at a so-called resting level. Under these circumstances, it is increasingly accepted that stimulation with FSH alone is sufficient to achieve adequate stimulation, fertilization, and pregnancy rates (13Tesarik J. Mendoza C. Effects of exogenous LH administration during ovarian stimulation of pituitary down-regulated young oocyte donors on oocyte yield and developmental competence.Hum Reprod. 2002; 17: 3129-3137Crossref PubMed Scopus (85) Google Scholar, 14Hull M.G. Armatage R.J. McDermott A. Use of follicle-stimulating hormone alone (urofollitropin) to stimulate the ovaries for assisted conception after pituitary desensitization.Fertil Steril. 1994; 62: 997-1003Abstract Full Text PDF PubMed Scopus (34) Google Scholar). The debate has thus shifted to focus on whether LH supplementation either as hMG or in recombinant form, might allow for an improvement in outcomes above those achieved with FSH alone. For example, several investigators have demonstrated a benefit to outcomes when LH supplementation is used (15De Placido G. Alviggi C. Perino A. Strina I. Lisi F. Fasolin F. et al.Recombinant human LH supplementation versus recombinant human FSH (rFSH) step-up protocol during controlled ovarian stimulation in normogonadotrophic women with initial inadequate ovarian response to rFSH. A multicentre, prospective, randomized controlled trial.Hum Reprod. 2005; 20: 390-396Crossref PubMed Scopus (143) Google Scholar, 16Lisi F. Rinaldi L. Fishel S. Lisi R. Pepe G.P. Picconer M.G. et al.Use of recombinant LH in a group of unselected IVF patients.Reprod Biomed Online. 2002; 5: 104-108Abstract Full Text PDF PubMed Scopus (48) Google Scholar). In contrast, other investigators have argued that LH supplementation is not necessary (17Cedrin-Durnerin I. Grange-Dujardin D. Laffy A. Parneix I. Massin N. Gale J. et al.Recombinant human LH supplementation during GnRH antagonist administration in IVF/ICSI cycles: a prospective randomized study.Hum Reprod. 2004; 19: 1979-1984Crossref PubMed Scopus (108) Google Scholar) or may lead to suboptimal production of oocytes and embryos (5Balasch J. Penarrubia J. Fabregues F. Vidal E. Casamitjana R. Mana D. et al.Ovarian responses to recombinant FSH or hMG in normogonadotrophic women following pituitary desensitization by a depot GnRH agonist for assisted reproduction.Reprod Biomed Online. 2003; 7: 35-42Abstract Full Text PDF PubMed Scopus (52) Google Scholar, 6Fabregues F. Creus M. Penarrubia J. Manau D. Vanrell J.A. Balasc J. et al.Effects of recombinant human luteinizing hormone supplementation on ovarian stimulation and the implantation rate in down-regulated women of advanced reproductive age.Fertil Steril. 2006; 85: 925-931Abstract Full Text Full Text PDF PubMed Scopus (55) Google Scholar). Against the backdrop of these conflicting reports, recent investigators have advanced the concept that ovarian stimulation therapy may require individualization, because the degree of pituitary suppression achieved may be variable in different patients (13Tesarik J. Mendoza C. Effects of exogenous LH administration during ovarian stimulation of pituitary down-regulated young oocyte donors on oocyte yield and developmental competence.Hum Reprod. 2002; 17: 3129-3137Crossref PubMed Scopus (85) Google Scholar). To this end, the concept of an LH window has been proposed wherein LH levels too high or too low can be detrimental (2Fischer R. Understanding the role of LH: myths and facts.Reprod Biomed Online. 2007; 15: 468-477Abstract Full Text PDF PubMed Scopus (22) Google Scholar, 18Shoham Z. The clinical therapeutic window for luteinizing hormone in controlled ovarian stimulation.Fertil Steril. 2002; 77: 1170-1177Abstract Full Text Full Text PDF PubMed Scopus (129) Google Scholar). Humaiden et al. (19Humaidan P. Bungum L. Bungum M. Andersen C.Y. Ovarian response and pregnancy outcome related to mid-follicular LH levels in women undergoing assisted reproduction with GnRH agonist down-regulation and recombinant FSH stimulation.Hum Reprod. 2002; 17: 2016-2021Crossref PubMed Scopus (100) Google Scholar) investigated this concept and demonstrated that less optimal outcomes are achieved in down-regulated cycles using recombinant FSH only when LH levels are in either the lowest or the highest quartile on day 8 of stimulation. However, others have not been able to confirm these results (20Balasch J. Creus M. Fabregues F. Civico S. Carmona F. Puert B. et al.Suppression of LH during ovarian stimulation: analysing threshold values and effects on ovarian response and the outcome of assisted reproduction in down-regulated women stimulated with recombinant FSH.Hum Reprod. 2001; 16: 1636-1643Crossref PubMed Scopus (120) Google Scholar, 21Penarrubia J. Fabregues F. Creus M. Manau D. Casamitjana R. Guimer M. et al.LH serum levels during ovarian stimulation as predictors of ovarian response and assisted reproduction outcome in down-regulated women stimulated with recombinant FSH.Hum Reprod. 2003; 18: 2689-2697Crossref PubMed Scopus (47) Google Scholar). A potentially complicating factor for the LH window theory is that measurement of serum LH levels is unlikely to be an accurate reflection of LH activity owing to its pulsatile release and variability in assays and bioactivity. The present study takes a slightly different approach to the question of individualizing LH supplementation. Given the known role of LH in the maturation of the oocyte in vivo, we hypothesized that patients with a high rate of oocyte immaturity may be manifesting a deficiency of LH bioactivity. In this study, we sought to determine if, in a cohort of patients with a high rate of oocyte immaturity during a cycle stimulated with FSH only, the addition of LH in a subsequent cycle would increase the yield of both mature oocytes and excellent-quality embryos. Our results show that indeed, in this particular cohort, the addition of LH to the gonadotropin regimen did increase the yield of mature oocytes as well as increase the number of embryos exhibiting excellent morphologic grade. The strength of this study lies in the matched-pair design. With each patient serving as her own control across two cycles, the role of potential confounders is limited. Because a primary finding of this study was yield of mature eggs, we sought to determine if other factors may have played a role in increasing the yield in a second cycle. Although our center uses strict follicular criteria for hCG trigger (two follicles >18 mm), we wanted to confirm that timing of trigger was not altered in the second cycles. Using matched-pair analysis, we did not note a difference in days of stimulation, number of follicles >17 mm, number of follicles >16 mm at hCG, or mean diameter of the two lead follicles at hCG across the two cycles. Collectively, these observations point to the addition of LH being the primary contributor to the increased yield of mature oocytes in the second cycle. A weakness of the study is the inability to fully account for regression to the mean; however, the inclusion of a control group (cohort 2) who also underwent an FSH cycle with a similarly high rate of immaturity but then went on to cycle again with FSH only is instructive. In this cohort, we did not observe an increase in either the number or proportion of mature eggs retrieved, the number of eight-cell embryos, or the number of top-quality embryos. Collectively, these results suggest that our findings in cohort 1 indicate a true biologic effect of LH supplementation. Another limitation of these findings is their inability to provide guidance for patients initiating their first cycle. Similarly, these findings do not indicate whether there is benefit of adding hMG to the stimulation protocol for those with average or above-average rates of maturity. Finally, because the analysis is based on cycles using hMG, it does not provide guidance on the use of recombinant LH. To our knowledge, this is the first study specifically to address supplementation with hMG in a cohort of patients with a previous high incidence of immature eggs. The future of ovarian stimulation may not lie in the utilization of new strategies, but rather an improved ability to individualize existing treatment modalities. To this end, our study provides evidence that in this discrete population, addition of hMG leads to an improved yield of both mature oocytes and embryos of excellent morphologic grade compared with use of FSH alone.
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