Send Orders for Reprints to [email protected] The Open Reproductive Science Journal, 2013, 5, 1-13 1 Open Access Ovarian Stimulation with Urofollitropin (uFSH) Results in a Lower Yield of Oocytes Compared to Recombinant FSH (rFSH), Nevertheless, uFSH is at Least as Effective as rFSH in Younger Patients: Preliminary Results of a Retrospective Study with Antagonist Protocols in an IVF/ICSI Program Peter Kemeter*, Monika Stroh-Weigert and Wilfried Feichtinger Wunschbaby Institut Feichtinger, Vienna, Austria Abstract: Objective: Differences in the mode of action between recombinant FSH (rFSH) and urinary derived FSH (uFSH) have been reported in cycles down-regulated by agonists. The aim of our study was to determine, if these differences also exist in cycles down-regulated by antagonists. Method: Antagonist cycles performed between 2009 – 2012 were divided into two groups: 1. Cycles stimulated with rFSH preparations: Follitropin alfa (n=203) and Follitropin beta (n=443) and 2. Cycles stimu- lated with Urofollitropin (n=405). Cetrorelix or Ganirelix were used as antagonists. All patients received 75 IU hMG additionally from day 6 of stimulation onwards up to the day of hCG administration. A logistic regression analysis was conducted to find the most significant parameters predicting hCG-positive pregnancy for 2471 IVF cycles. The results demonstrated that the predictors such as age of patients and number of cycles ever per- formed made negative contributions and number of oocytes retrieved and number of embryos transferred made positive contributions to prediction. Taking this into consideration, comparable groups could be created by including only first- ever IVF cycles with more than 10 oocytes retrieved and 2 embryos transferred. Thus, the final sample for comparison included 98 patients in the rFSH-group and 27 patients in the uFSH group. Results: There were no differences in basic personal data and gonadotropin consumption between the groups. Stimulation with rFSH resulted in a higher yield of oocytes compared to uFSH (15,6 vs. 14,4), however, the results of the following reproductive outcome parameters were all in favor of uFSH when rFSH and uFSH were compared: oocyte maturation rate (76.5% vs. 79.0 %), fertilization rate (53,6% vs. 58,6%), embryo score 4 rate (25,7% vs.. 31,1%), hCG-positive pregnancy rate (43,9% vs. 59,3%), clinical pregnancy rate (33,7% vs. 44,4%), embryo-cryopreservation rate (19,3% vs. 30,5%) and abortion rate (14,0% vs. 12,5%). Conclusions: These results seem to support the concept that uFSH produces fewer oocytes than rFSH, but the oocytes produced by uFSH are, on an average, of better quality than those produced by rFSH. Basic studies have shown that dif- ferent FSH isoforms with different elimination kinetics in the two gonadotropin preparations could be responsible for the different effects. However, the results have to be confirmed by well designed prospective randomized studies. Keywords: Urofollitropin, uFSH, rFSH, FSH glycosylation, IVF. BACKGROUND fection of the human FSH gene into Chinese hamster ovary (CHO) cells. The resulting clones are screened for FSH pro- Ovarian stimulation with gonadotropin preparations has duction and activity as well as genetic stability. A single cell become an integral part of assisted reproduction treatment. is then selected and cultured to create a working cell bank At present, two recombinant follicle stimulating hormone (WCB) of identical cells that produce rFSH which is then (rFSH) preparations are on the market: follitropin-alfa (Go- harvested from the culture supernatant [1]. An alternative to nal-F, Serono) and follitropin-beta (Puregon, MSD). Both rFSH is urinary FSH (uFSH), which is purified from the have been developed through genetic engineering, by trans- urine of post-menopausal women [2]. FSH is a complex glycoprotein composed of protein and carbohydrate. The protein part consists of two dissimilar *Address correspondence to this author at the Wunschbaby Institut Feicht- inger, A-1130 Vienna, Lainzerstr. 6, Austria; Tel: + 436649224886; non-covalently linked polypeptide subunits: alfa and beta Fax: +43125330334922; E-mail: [email protected] [3], with the beta subunit conferring the biological specific- 1874-2556/13 2013 Bentham Open 2 The Open Reproductive Science Journal, 2013, Volume 5 Kemeter et al. ity of FSH (the alfa subunit is common to all the pituitary lis; and hormone levels in the normal range (FSH < 14 glycoprotein hormones). The carbohydrate part consists of mIU/ml, prolactin < 30 ng/ml, TSH < 2.0 uU/ml). Exclusion four side chains, referred to as glycans, each composed of criteria were abnormalities of the uterine cavity seen by varying numbers of sugars (oligosaccharides) and sialic acid. sonography. Due to their sialic acid content, more heavily glycosylated Patients were allocated to one of three groups (Figs. 1-3) molecules have a more acidic isoelectric point (pI). Mole- by the physicians: cules with the same pI are referred to as isoforms, and sev- ® eral studies have shown that the anterior pituitary contains a Group I = Follitropin-alfa (Gonal-F ) + Cetrorelix (Ce- ® spectrum of FSH isoforms with not only different isoelectric trotide ); properties, but also different bioactivities and different circu- ® Group II = Follitropin-beta (Puregon ) + Ganirelix (Or- lating half-lives due to the micro-heterogeneity of the carbo- ® hydrate side-chains [4, 5]. This mixture of different carbohy- galutran ); ® ® drate moieties produced by the pituitary gland is modulated Group III = uFSH (Fostimon ) + Cetrorelix (Cetrotide ). by the ovulatory cycle: in the early follicular phase heavily sialylated, acidic isoforms with long half lives in vivo and There was no randomization of patients, with doctors free low in-vitro biological potency predominate, whereas in the to decide which treatment to prescribe. However, their deci- peri-ovulatory phase, the less-sialylated, less acidic isoforms, sion may have been influenced by personal experience, price with short in vivo half-lives and high in-vitro biological ac- differences, product availability, information from the phar- tivity are more prevalent. Based on these considerations, it maceutical companies, seminars, etc. has been assumed that the more acidic isoforms stimulate the follicular maturation process in a longer, but less intense To prime menstruation, all patients received tablets pre- manner, while the less acidic isoforms appearing to provide a pared by the pharmacist containing 2 mg norethisterone ace- short, but potent stimulus necessary for the induction of ovu- tate and 0.01 mg ethinyl estradiol, three times daily for 10 lation [6, 7]. days, starting on a Friday between day 16 and 22 of the cy- cle, with the final dose on a Sunday. At the same time, pa- Various studies have compared rFSH with Human tients received prednisolone (2.5 mg in the morning and 5 Menopausal Gonadotropin (HMG) and more or less purified mg in the evening). This adjuvant mild corticoid therapy FSH preparations for ovarian stimulation in IVF/ICSI. While earlier studies reported rFSH to be more effective than HMG (which was continued throughout the treatment cycle and up and/or uFSH [8-13], others found no significant difference to the ninth week of pregnancy), has been found to suppress [14-21], and some more recent studies have reported uFSH excessive adrenal androgen production, which can affect to be superior to rFSH [22-24] or “at least as effective” [25]. ovarian steroid metabolism [31, 32]. In addition to the different FSH preparations, all the patients received an There is a highly-purified uFSH preparation (Fostimon; injection containing 75 IU FSH and 75 IU LH (Merional®) IBSA, Switzerland) that belongs to a new generation of uri- daily from stimulation day 6 until the day of hCG admini- nary FSH preparations that have especially acidic glycosyla- stration, to avoid a possible lack of LH caused by the an- tion content. A number of advantages of this product over tagonist. Exogenous LH supplementation has been shown to rFSH preparations have been reported, including: signifi- benefit patients older than 35 years of age [33-36], and pa- cantly more top-quality embryos [26]; consumption of sig- nificantly fewer units of FSH in patients older than 39, tients with a sub-optimal response to FSH-only preparations achieving equivalent embryo development and pregnancy (poor responders) [37-40]. rates [27]; significantly higher implantation and pregnancy In all groups, ovarian stimulation commenced on the Fri- rates when Fostimon was administered for the first 6 days, day after the last dose of 2 mg norethisterone acetate and followed by rFSH, compared to rFSH alone [28]; signifi- 0.01 mg ethinyl estradiol (Figs. 1-3). In Group I, daily doses ® cantly less FSH consumption in patients achieving blastocyst of Gonal-F were 225 IU up to day 5, then 150 IU from day ® transfers on day 5 [29]; and a significantly higher number of 6 to the day of hCG administration. Cetrotide (0.25 ® top quality embryos and transferring of cryopreserved em- mg/day) and Merional were administered from day 6 (Fig. bryos in PCO-patients [30]. 1). The other groups followed a similar protocol, with Pure- ® ® ® Since these studies were all conducted using agonist cy- gon instead of Gonal-F , and Orgalutran instead of Ce- ® ® ® cles, and we predominantly use antagonist cycles, we were trotide for Group II (Fig. 2), and Fostimon and Cetrotide interested in determining whether the reported advantages of for Group III (Fig. 3). During the luteal phase, patients re- ® Urofollitropin could be achieved in antagonist cycles as well. ceived micronized progesterone (Utrogestan , Meda Accordingly, this study reports a retrospective comparison of Pharma, Austria; taken orally: 3 × 200 mg/day), together ® ® ® both rFSH preparations (Puregon , MSD and Gonal-F , with 20 mg dydrogesterone (Duphaston , Solvay, Austria) ® ® Serono) with Fostimon . and 2 mg estradiol valerate (Progynova , Schering, Ger- many) up to week 9 of pregnancy. DESIGN All patients signed an informed consent that they agreed Patients were selected for the study if they had undergone to the inclusion of their data in the analysis.