AL-AZHAR ASSIUT MEDICAL JOURNAL VOL 13, NO 1, JANUREY 2015

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1 AL-AZHAR ASSIUT MEDICAL JOURNAL VOL 13, NO 1, JANUREY 2015 EVALUATION OF MODIFIED FLARE UP VERSUS MODIFIED LONG PROTOCOLS FOR LOW PESPONDERS HOW WERE UNDERGOING INTRACYTOPLASMIC SPERM INJECTION EMBRYO TRANSFER Hassan Abd Rabou International Islamic center for Population Studies and Researcher,AL-Azhar University ABATRACT Objective: to evaluate two COH protocols designed for poor ovarian responders undergoing ICSI. Design: Randomized prospective study. Setting: Assisted reproductive technology unit in International Islamic Center for Population Study and Research (IICPSR), AL-Azhar University Patient(s): Fifty four poor ovarian responder patients were recruited on the basis of there results in previous cycle(s). Intervention: Modified long protocol in which a standard GnRH agonist dose was used until pituitary DR, after which the GnRH agonist dose was halved during stimulation, or modified flare protocol in which high dose of GnRH agonist administrated for the 1 st four days, followed by a standard GnRH agonist dose. Main outcome measure(s): Number of meta two phase oocyle collected. Results: A total of 54 infertile women with the patient's age ranged from 20 to 37 years were included in this study. 30 patients (55.5%) were stimulated with modified short protocol while 24 patients (45.5%) were stimulated with modified long protocol. With the exception of total HMG dose (number of ampoules), there had been no significant differences in the studied characteristics among the patient stimulated with the different protocols. There have been statistically significant differences among the patient stimulated with the different protocols with respect to number of follicles 20mm, E2 HCG, and number of meta phase ll oocyes (MII) where P-value were < The mean number of follicles 20mm was, 5.5±1.4 in short protocol and 12.9±4.4 in long protocol. INTRODUCTION AND AIM OF STUDY The poor ovarian responder patients: The management of the "poor ovarian responder" in controlled ovarian hyperstimulation (COH) around the world has been a long-standing challenge. Although there is no clear, universal definition of the ''poor responders'' patient, they tend to represent about 10% of patient undergoing COH treatment for of ART, despite advances in ovarian stimulation protocols and IVF laboratory techniques (Gautam et al., 2004; Leon and Mark, 2005). The original definition of poor response of COH was based only on low oestradiol concentrations. But most authors define the poor ovarian response in patients that develop less than four mature oocytes by the time of human chorionic gonadotropin (hcg) administration, or a peak estradiol (E2) of less then 500pg/ml during IVF or the patient having undergone a previous IVF cycle with a poor stimulation outcome (Guttam et al., 2004; kailasam et al., 2004; Roest et al., 2006). This definition generally implies failure to achieve a certain number of mature follicles or a certain estrogen level in relation to the amount of ovarian stimulation that has been given (Leon and Mark, 2005; perez et al., 2007). Despite these differences in definition '' poor responders'' represent a heterogeneous group of patients who can be divided clinically into; patients with low ovarian reserve and patients with normal ovarian reserve who are inherently low responders to gonadotrophin stimulation. Advanced age, previous ovarian surgery, pelvic adhesions and high body high body mass index may be associated with poor ovarian response (Keay et al. 2002; Akande et al., 2003; Kupker et al., 2005). Ovulation induction is a process of promotion of follicular growth and development culminating in ovulation (Gutam et al., 2004). Prolonged elevation of FSH can be achieved by direct administration of exogenous FSH (Rabe et al., 2002). However, in about 15% of cycles stimulated, the exaggerated estradiol levels due to the multifollicular response provoke high LH concentrations during the follicular phase or an untimely spontaneous LH concentration during the follicular phase or an untimely spontaneous LH surge. This may lead to impaired oocyte quality or more often, to cycle cancellation. For this reason, to avoid interference from endogenous gonadotrophin secretion; a combined therapy of gonadptrophins and GnRH agonists has been gradually introduced (Tarlatzis and Grimbizis, 2002; Paul and Carolin, 2005). GnRH agonist administration leads to prolonged agonistic action on the GnRH stability. The initial increase gonadotrophin secretion from pituitary cells, a phenomenon known as the flare-up effect which results from 78 P a g e

2 Hassan Abd Rabou VOL 13, NO 2, APRIL 2015 activation of mechanisms that are identical to those observed after natural GnRH agonist administration. However, the prolonged administration of agonists with there chronic action on pituitary gonadotrophs suppresses pituitary function. This is due to downregulation of the GnRH receptors and the inhibition of post-receptor mechanisms (pituitary desensitization) that are responsible for the synthesis and release of gonadotrophins which block the positive oestradiol (E2) feedback to the pituitary and the resulting untimely LH surges (Dayas, 2001). The GnRH agonist treatment may suppress endogenous LH levels below those necessary for necessary for normal follicular development in some women. Because only about 1% of LH receptors need to be occupied to support normal follicular steroidogenesis, these low levels of LH are sufficient to meet the need in most women stimulated with ufsh or rfsh alone (Balasch et al., 2006). The only disadvantage is the GnRH agonist treatment sometimes blunts the response to subsequent gonadotrophin stimulation and increases the dose and duration of gonadotrophin therapy required to stimulated follicular development, which increase the total cost of treatment (Meldrum et al., 2005). These combinations associated with fewer than 2% of cycle cancellation due to a premature LH surge which previously had necessitated cancellation of approximately 20% of all IVF cycles before oocyte retrieval, which was met by direct inhibitory effect of GnRH antagonist or after down-regulation with a GnRH agonist, stimulation could continue until follicles were larger and more mature (Daya, peter, 2006). The two successive actions of GnRH agonists have permitted the design of different protocols for ovarian stimulation. The immediate stimulatory section is used in the socalled ''short'' and ''ultrashort'' in order to enhance follicular recruitment in the early follicular phase. On the other hand, the secondary inhibitory action is used in the ''short'' and ''long'' protocols suppress endogenous LH secretion and prevent premature LH surges (Janssens et al., 2005). Ideal ovarian stimulation regimen for IVF should have a lower cancellation rate, minimize drug costs, risks and side effects, required limited monitoring, and maximize singleton pregnancy rates (Leon and Marc, 2005). Several regimens are available for GnRH agonist administration during controlled ovarian hyperstimulation, of which the most common and extensively used are the long and short protocols in different variations. The ''long protocol'' is the preferred ovarian stimulation regimen for ART. This is the most traditional and widely employed protocol (reports for the year 2000 that more than 80% of stimulated cycles were performed according to long protocol) (Wang et al., 2002). Because the egg yield is grater, the large number of embryos the probability of having an optimal number of embryos for transfer and excess embryos cryopreservation is greater (Meldrum et al., 2005). The '' short of flare'' protocol is an alternative stimulation regimen that exploits both the initial brief agonistic phase of the response to along-acting GnRH agonist and the subsequent suppression of agonistic phase of endogenous gonadotrophin secretion induced by longer-term treatment, then exogenous gonadotrophins starting on cycle day 3. The doses of gonadotrophin stimulation, if needed, are based on response and indications for hcg administration are the same as in the long protocol (Karancle et al., 2005; Padilla et al., 2005). Ovarian response in young ovulating women under-going in vitro fertilization (IVF) treatment, the standard stimulation protocol can result in either poor response in ovarian hyperstimulation syndrome (Balasch et al., 2006)/ Patients and Methods Patients: In this study, we prospectively recruited 54 ovulating women, ovulation was documented indirectly by mid luteal progesterone levels. Patients were recruited from the ongoing assisted reproduction program in Assisted Reproductive Technology Unit in International Islamic Center for population Study and Research (IICPSR), AI-Azher University. All the women were candidates for ICSI-ET who had a poor response during a previous cycle within months before participation, where standard long or short protocol for controlled ovarian stimulating where administered. In the previous cycle, dorm or a daily subcutaneous 100µg of the GnRH agonists were used for the long protocol, while in the short protocol, a daily subcutaneous 100µg of the GnRH agonist was administered from the 1 st day of 79 P a g e

3 AL-AZHAR ASSIUT MEDICAL JOURNAL VOL 13, NO 1, JANUREY 2015 menstruation in short protocol, while in the long protocol HMG were administered from the 2 nd day of menstruation in short protocol, while in the long protocol HMG administration started when E2 serum level less then 50pg/ml. A poor response were diagnosed when less than follicles with main follicular diameter 18 or more at the time of HCG administration, or serum E2 level less than 500pg/ml women excluded from the study if the basal FSH >15IU/ml. Treatment: Modified long protocol (GnRH agonistmini dose protocol): AII patients GnRH agonist started day 21 of the previous cycle at a daily dose of 100µg until menstruation. On menstruation patients were evaluated for down regulation (serum E2 level less than 50pg/ml, no follicle more than 15 mm and endometrial thickness less than 6mm). Where pituitary down regulation was confirmed the dose of GnRH was decreased to 50µg/day) was termed mini dose as suggested by Feldberg et al. and continued until the day of HCG administration (Meldrum et al., 2005). Modified short protocol: AII patients were pretreated oral contraception cessation of this treatment induce withdrawal bleeding, on the 1 st day of the withdrawal bleeding, subcutaneous administration of high dose GnRH agonist 200µg/ day was commenced and continued for 4 days, then the GnRH agonist 200µg/ day was commenced and continued for days, then GnRH agonist dose was reduced to 100µh/ day and continued until the day of HCG demonstration. Ovarian stimulation was commenced on the 2 nd day of withdrawal bleeding one day after administration of GnRH analoge. 4 ampules of HMG were commenced on the 3 rd day withdrawal bleeding. The dose and duration of gonadotrophin treatment required to induce successful ovulation varied among women. Typical starting dose gonadotrophins ranged between 150 and 300IU (2-4 ampoules) of uhmg daily, depending on age, Weight, results of ovarian reserve testing and the response observed in any previous trial. Ovarian reserve testing and the response observed in any previous trial. The dose was adjusted according to the patient's response to stimulation from cycle day 7 (6 day from stimulation) as assessed by TV U/S and / E2 level, either a step up or step down was used. Cycle monitoring: In general, follicular development was first monitored by transvaginal ultrasonography 6 days after stimulation and subsequently every other day. Sonography was performed daily when the leading follicle exceeded 16 mm in diameter. Ovulation was induced by IU human CG (hcg), IM Oocyte retrieval by transvaginal ultrasound guided aspiration under general anesthesia was generally performed approximately hours after hcg administration. Intracytoplasmic sperm injection sperm injection was performed in all patients, according to the protocol of Van Steirteghem et al. (1993). Statistical analysis: The characteristics of the studied patients were expressed as mean ±SD. In order to compare patients' characterstics among different stimulation protocols, analyses of variance (ANOVA) were used as appropriate. P-value <0.05 were considered statistically significant. The characteristics of the ovarian response variables were expressed as mean ±SD. In order to compare patients' outcome among different stimulation protocols, analyses of variance (ANOVA) were sued as appropriate. P-value <0.05 were considered statistically significant. Data were analyzed by Statistical Analysis System (SAS version 9.0, USA) statistical software. Ethical consideration: This study was approved by the regional authority of the reproductive technology (ART) unit, International Islamic center for Population Study and Research (IICPSR), AI-Azhar University. Each patient received a full explanation of the purpose of the study and a written consent was taken from each studied patient. All patients were enrolled in this study if only they gave a free and informed consent. All the data were manipulated confidentially. RESULTS A total of 54 infertile women included in this study. The patients' age ranged from 20 to 37 years. 30 patients (55 %) were stimulated with modified long protocol. The overall results of this study are summarized in following tables and figures: 80 P a g e

4 Hassan Abd Rabou VOL 13, NO 2, APRIL 2015 Table (1): patients Variableª Characteristics of the studied Stimulation protocol P- Short (n=30) Long (n=24) value* Age in years 30.0± ± BMI (kg/m2) 27.1± ± Cycle duration in days 29.0± ± Total HMG dose (No. of ampoules) 41.3± ± Serum FSH (IU / I) 7.1± ± Serum LH (IU / I) 4.2± ± PRL 11.7± ± Serum E2 (n mol / l) 70.7± ± ª Variable is presented by mean ±SD or (%). *P-value calculated for the difference stimulation protocols. Table (1) represents characteristics of all the studied patients (n= 54) and compare these characteristics in patients with different stimulation protocols. With the exception of total HMG dose (number of ampoules), there had been no significant differences in the studied characteristics among the patient stimulated with the different protocols. The mean age of the studied patients was 30.0±5.4 and 30.8±4.6 for the short and long protocol respectively with significant statistical difference (p=0.01). The mean number of ampoules given to the studied patients was 41.3±4.8 in short protocol, and 37.5±6.3 in long protocol and showed significant statistical difference (p=0.01). Table (2): Mean and SD ovarian response variables of all studied patients and allelic variant groups Variableª Stimulation protocol Short (n=20) Long (n=14) P-value* Number of follicle 20mm 5.5± ±4.4 <0.0001** E2 HCG 747± ±858 <0.0001** Endometrial thickness 10.8± ± Number of MII 3.1± ±4.0 <0.0001** * P-value calculated for the difference stimulation protocols. ** The difference is among two studied stimulation protocols. Table (2) displays the mean and SD of the ovarian response variables in studied patients in different stimulation protocol. There have been statically significant differences among two studied stimulation protocols with respect to number of follicles 20mm, E2 HCG and number of Meta phase II oocytes (MII) where p-values were < the mean number of follicle 20mm was 5.5±1.4 in short protocol and 12.9±4.4 in long protocol DISCUSSION Soon after the introduction of GnRH agonist into clinical protocol, their use extended to treatment of low responders undergoing IVF. Although, early studies were optimistic and suggested that long GnRH agonist protocols could be beneficial for low responders, subsequent clinical experience has yielded disappointing results. In many cases, ovarian suppression with GnRH agonist resulted in excessive dampening of the ovarian response to hormonal stimulation and complete refractoriness to gonadotrophin stimulation. Cancellation rates due to lack of ovarian response were unacceptably high, and hormonal stimulation was excessively prolonged, with increased cost and duration of treatment and only a marginal benefit in the mean E2 maximum response and the yield of mature oocyte (Albano et al., 2000; Balasch et al., 2001; Balasch and Gabregues, 2002; Shoham,2002). Initiation of GnRH agonist therapy early in the follicular phase, which takes advantage of the initial endogenous gonadotrophin flare-up also has been proposed as a better stimulation protocol for low responders (Balasch et al., 2006). It is believed that the flare-up effect enhances the effect of exogenous gonadotrophins and in theory eliminates excessive ovarian suppression. However, patients who receive GnRH agonist in this early phase have an increase un gonadotrophin levels that may also induce enhanced ovarian androgen release, elevated follicular phase progesterone levels (from corpus luteum rescue), and a secondary decline in follicular recruitment and oocyte quality, leading to decreased ongoing pregnancy rates compared with those who receive GnRH agonist in the long protocol (Judith et al., 2005). Few data exist on the dose-effect relationship for the different GnRH agonist preparations used in the short or long protocol. In this study we investigate changes to the GnRH agonist doses in both the short and the long protocol. In this study we investigate changes to the GnRH agonist does in both the short and the long protocol. For the sort protocol, increasing the agonist dose during the flare phase was not found to improved follicular recruitment. 81 P a g e

5 AL-AZHAR ASSIUT MEDICAL JOURNAL VOL 13, NO 1, JANUREY 2015 A partial explanation for our observations may be found in a recent report by Balasch et al. (2001), who studied the hormonal profiles during the flare-up period using 25µg and 100µg of triptorelin in the short protocol. No significant difference in the magnitude of FSH and E2 release was observed between the groups, but the maximal plasma LH level was significantly reduced after injection of 25ug of triptorelin. It was suggested that in the flare protocol, a lower dose of GnRH agonist induces a hormonal flare-up that is better for optimal follicular recruitment. Clearly, the mega-dose that were have used for flare induction (200µg) is much higher that the doses of 25 and 100µg used by Balasch et al., (2001). We the reason for the poor outcome observed in this group may be related to a higher LH output during the flare period. There is evidence of an adverse effect of high endogenous LH level curing the follicular phase, which led to the establishment of the ceiling theory (Loumaye et al., 2003). According to this theory, beyond a certain ceiling level, LH suppresses granulose cell proliferation and initiates atresia of less mature follicles. This may explain why significantly less oocytes were obtained using the high dose of GnRH for flare induction. Amicro-dose flare regimen has also been proposed and used successfully in low responders. In these regimens, the dose GnRH agonist is reduced to minimal amount that can successfully induce endogenous gonadotropin release In theory, micro-flare regimens decrease the enhanced LH, P, and androgen secretion associated with traditional flare regimens. Although the lowest dose of GnRH agonist that can induce gonadotrophin release in humans is not known, doses as low as 20 to 40µg of leuprolide acetate twice daily, with or without growth hormone supplementation, have been successfully used for this purpose (Daya et al., 2001; Balasch and Fabregues, 2002; Albano et al., 2000 Janssens et a., 2000). Favorable ovarian response and cycle outcome were observed. Compared to cycles without use of GnRH agonist, a higher amount of exogenous gonadotrophins is required to obtain an adequate ovarian response in the long GnRH agonist protocol. This phenomenon, which may be partially related to the state of hypophyseal desensitization and the degree of LH suppression, hassled investigators to propose use of a lower dose of GnRH agonist, especially for patients with a previous low response to gonadotropin stimulation. In an attempt to maximize ovarian response without losing the benefits of GnRH agonist down-regulation, Fady et al., use the mini- dose GnRH agonist, protocol in low responders with elevated basal FSH levels They found that patients who received triptorelin, 100µg/d SC from the mid-luteal phase until menstruation and than 50µg/d thereafter, had higher peak E2 levels, more oocytes recovered, and more embryos transferred. They also noted a trend toward improved pregnancy and implantation rates and a lower spontaneous abortion rate. Further support to this concept is derived from the first prospective, placeebocontrolled double-blind study to deter-mime the lowest effective dose for triptorelin to prevent an LH surge during IVF (Janssens et al., 2000; Janssens et al., 2005). A total of 240 women were randomized to placebo or to one of here doses of triptorelin: 15, 50 or 100µg/d. The LH surge occurred in 23% of placebo-treated patients but in none of the triptorelin recipients. Significantly more oocytes and embryos were obtained in patients receiving 50 or 100µg of triptorelin. No dose relationship was obtained in terms of rates of rates of implantation, pregnancy ongoing pregnancy. Live birth, or take-home babies. Daily administration of 15µg of triptorelin was sufficient to prevent apremature LH surge, and 50 µg was equivalent to 100 µg in terms of IVF results. Thus, the dose of triptorelin can be safely reduced to 50 µg/d, which may be beneficial for low responders. In both protocols, treatment with different combinations of steroids preceded administration of GnRH agonist. In the modified flare-up protocol, an oral contraceptive was given for 2 weeks and GnRH agonist therapy was commenced on menstruation. Pretreatment with oral contraceptive is believed to eliminate corpus luteum from the prior cycle, so that the flare effect of GnRH agonist cannot ''rescue'' the preexisting corpus luteum and its associated premature production. Furthermore, precycle treatment with estrogen-progestin may augment the subsequent response to gonadotrophins and prevent premature LH surges. The long mini-luteal GnRH agonist protocol was preceded by a course of oral progestin. The original goal of this modification 82 P a g e

6 Hassan Abd Rabou VOL 13, NO 2, APRIL 2015 was to prevent ovarian cyst formation, which is a common complication of GnRH agonist therapy. Ovarian cyst formation after GnRH agonist administration has been suggested to be typical for low responders and is a reliable predictor of poor stimulation and low pregnancy rates in a given cycle. Although the pathophysiology of ovarian cyst formation following GnRH agonist. Administration, the lower the incidence of cyst formation (Paul and caroline, 2004).Progestagen pretreatment directly inhibits endogenous gonadotrophin secretion and influences the pattern of gonadotrophin and hypothalamic GnRH secretion. There prospective, randomized studies have demonstrated the successful use of progestins to prevent ovarian cyst formation during pituitary suppression in IVF cycles (Gautam et al., 2004). On the basis of the above observations, pretreatment with a progestin for low responders who received the long protocol, higher clinical pregnancy rates that were observed with progestin pretreatment on the three studies that evaluated this approach (Gautam et al., 2004). Addition of a progestin to the drug regimen did not completely eliminate ovarian cyst formation, as 4 of 31 (12.9%) patients developed cyst. This is probably related to the increased risk for cyst development in low responders (Paul and Caroline, 2004; Peter, 2006). Whether this modification to the long protocol contributed to the significantly higher oocyte yield and the trend toward increased clinical pregnancy rates must be further evaluated. Although the clinical pregnancy rate per cycle (22.5%) and pertranssfer (25.9%) were favorable with the long mini-dose protocol, the sample size of our study is insufficient to make meaningful calculation; considerably larger samples are required to evaluate the effect of various interventions on pregnancy rates after IVF. Nevertheless, others have also noted improved pregnancy rates in low responders after use of specifically designed stimulation protocols (Keay et al., 2002; Paul and Caroline, 2004). Our sample consisted of patients with very poor prognosis. In addition to being low responders, our patients also had had repeated failure in previous IVF attenpts (mean of 6.4±5.6 past failed cycles) and advanced maternal age (38.8±3.7 years). The very poor prognosis in our sample is uncommon for countries in which the full cost of IVF is provided by the national health insurance program except for extreme cases. Couples are entitled to an almost unlimited number of IVF attempts, as long as embryos are available for transfer and up to the birth of two children. As consequence of this policy, low responders with multiple failed attempts of IVF-ET are commonly seen in Israeli clinics, including ours. The inclusion of low responders with poor prognosis and advanced reproductive age explains in past why we failed to observe the shorter duration of stimulation and decreased gonadotropic requirements typically obtained with the short protocol. Furthermore, we found that despite the superiority of the mini-dose protocol, which was demonstrated in the current study, some low responder patients have better performance on the short protocol. Thus, there is no universal protocol that should be uniformly applied to all low responders. Treatment protocol should be individually tailored, and other protocols, such as the microflare or a GnRH antagonist protocol appears to yield the best results and is therefore our protocol of choice for low responders undergoing. IVF. REFERENCES - Akande VA; Fleming CF; Hunt LP; keay SD; Jenkins JMB (2003): FSH versus chronological ageing of oocyte, distinguishable by raised FSH in relation to the success of IVF treatment. Hum Reprod; 17:2. - Albano C; Felberbaum RF; Smitz J; Ruethmuller-Winzen H; Engel J; Diedrich K; Devroey P; The European Cetrorelix Study Group (2000): Ovarian stimulation with HMG: results of a prospective randomized phase lll European study comparing the luteinizing hormone-releasing hormone- releasing hormone (LHRH)-antagonist cetrorelix and the LHRH-agonist buserelin. Hum Reprod; 15: Balasch J; Wang PT; Lee RK; Su JT; Hou JW; Lin MH; Hu YM (2006):Cessation of low dose gonadptrophin releasing hormone agonist therapy followed by high-dose gonadptrophin stimulation yield a favorable ovarian response in poor 83 P a g e

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