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Administration of atosiban in patients with endometriosis undergoing frozen–thawed embryo transfer: a prospective, randomized study
ORIGINAL ARTICLE: ENDOMETRIOSIS
Administration of atosiban in patients with endometriosis undergoing frozen–thawed embryo transfer: a prospective, randomized study Ye He, M.D., Huan Wu, M.D., Xiaojin He, M.D., Ph.D, Qiong Xing, M.D., Ping Zhou, M.D., Yunxia Cao, M.D., Ph.D., and Zhaolian Wei, M.D., Ph.D. Department of Obstetrics and Gynecology, Reproductive Medicine Center, The First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China
Objective: To examine the effects of atosiban, given before transfer of frozen–thawed embryo to women with endometriosis (EMs). Design: A prospective, randomized, controlled clinical trial. Setting: University hospital and IVF center. Patient(s): One hundred twenty women with endometriosis undergoing frozen–thawed embryo transfer were randomly allocated into the atosiban treatment and the control groups. Another 120 women with infertility due to tubal factor were enrolled into a tubal factor group, to compare serum oxytocin (OT) and prostaglandin (PG)F2a levels and uterine contractions with the endometriosis group. Intervention(s): In the endometriosis treatment group, a single bolus (6.75 mg, 0.9 mL per vial) of atosiban was administrated before ET. Main Outcome Measure(s): Implantation rate and pregnancy rate. Result(s): Serum OT level (1.89 0.33 vs. 1.66 0.32 ng/L), PGF2a (2.83 0.34 vs. 2.36 0.35 ng/L) level, and uterine contractions (2.5 1.2 vs. 1.8 1.0 waves per minute) in the endometriosis group were all significantly higher than in the tubal factor group. The clinical pregnancy rate per cycle and implantation rate per transfer were 58.3% and 41.0%, respectively, in the atosiban treatment group, significantly higher than in the control group (38.3% and 23.4%, respectively). Conclusion(s): Women with endometriosis showed higher serum OT level, PGF2a level, and uterine contractions. Atosiban treatment before ET in endometriosis is effective in the priming of the uterus, suitable for embryo implantation. This is the first study to evaluate the effect of atosiban treatment in patients with endometriosis. Use your smartphone Clinical Trial Registration Number: ChiCTR-IOQ-14005715. (Fertil SterilÒ 2016;-:-–-. to scan this QR code Ó2016 by American Society for Reproductive Medicine.) and connect to the Key Words: Atosiban, clinical pregnancy rate, endometriosis, oxytocin, uterine contractility Discuss: You can discuss this article with its authors and with other ASRM members at http:// fertstertforum.com/hey-atosiban-endometriosis-fet/
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ndometriosis is a benign gynecologic disorder characterized by the presence of endometrial tissue outside the uterus and is accompanied by pain and infertility (1). The disease affects approximately 10% of women of reproductive age and
20%–50% of infertile women (2, 3). In vitro fertilization is currently the most effective treatment for endometriosis-associated infertility (4), especially for those who have experienced surgical treatment but are still infertile. Although the issue of whether
Received November 5, 2015; revised April 2, 2016; accepted April 14, 2016. Y.H. has nothing to disclose. H.W. has nothing to disclose. X.H. has nothing to disclose. Q.X. has nothing to disclose. P.Z. has nothing to disclose. Y.C. has nothing to disclose. Z.W. has nothing to disclose. Reprint requests: Zhaolian Wei, M.D., Ph.D., The First Affiliated Hospital of Anhui Medical University, Department of Obstetrics and Gynecology, Reproductive Medicine Center, 218 Jixi Road, Hefei, People's Republic of China (E-mail: [email protected]). Fertility and Sterility® Vol. -, No. -, - 2016 0015-0282/$36.00 Copyright ©2016 American Society for Reproductive Medicine, Published by Elsevier Inc. http://dx.doi.org/10.1016/j.fertnstert.2016.04.019 VOL. - NO. - / - 2016
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the presence of endometriosis has a negative impact on the outcome of IVF has not been resolved (5), previous studies have shown that the pregnancy rate is reduced in infertile women with endometriosis undergoing IVF when compared with tubal factor infertility (6). The changed receptivity of the endometrium may account for this reduced performance. Ideal intrauterine conditions that enable implantation include appropriate endometrial states, sufficient endometrial perfusion, and absence of excessive uterine contractions (7). A significantly higher uterine contraction 1
ORIGINAL ARTICLE: ENDOMETRIOSIS frequency was found in women with endometriosis than in women without endometriosis (8), which may contribute to the development of endometriosis as well as to the reduced IVF success rate in women with endometriosis. Oxytocin (OT), a nonapeptide synthesized by neurons of the supraoptic nucleus and released from the posterior pituitary gland, has diverse effects on the female reproductive system (9). It is known to be a factor causing uterine contractions. It has also been shown in animal models that endometrial cells contain oxytocin receptors (OTRs) and that OT has the capacity to trigger the production of prostaglandin (PG)F2a from these cells (10, 11). Steinwall et al. (12) demonstrated that OT may be synthesized in the endometrium of nonpregnant women, particularly in the glandular epithelial cells. Hormone released from these sources may have a paracrine action on the uterus. Furthermore, Mechsner et al. (13) reported that OTRs are expressed in smooth muscle cells and in the epithelial cells of peritoneal endometriotic lesions and ovarian endometriotic cysts of premenopausal women, suggesting that OT might participate in the pathogenesis of endometriosis and contribute to infertility. It is well known that an increase of plasma OT levels in pregnant women stimulates uterine contractions (14). Thus, we speculate that a hyperactivated autocrine/paracrine OT/ OTR system in endometriosis may result in uterine hyperperistalsis and poor endometrial receptivity. The therapeutic efficiency of atosiban, an OTR antagonist, was confirmed in a report using endometriotic rat models in which the volumes of endometriotic implants and proliferating cell nuclear antigen expression levels were significantly reduced in the atosiban treatment group (15). On the basis of this background, we designed the present study to investigate the effect of atosiban used before ET in patients with endometriosis and analyze serum OT and PGF2a levels and uterine contractions in patients with endometriosis.
MATERIALS AND METHODS This was a randomized clinical trial for the first part described. The part comparing endometriosis patients with tubal factor patients was a prospective cohort study. The study was performed from December 2014 to July 2015. A total of 120 patients with endometriosis undergoing IVF/ET using cryopreserved embryos in the reproductive center of the First Affiliated Hospital of Anhui Medical University were randomized into treatment (n ¼ 60) and control (n ¼ 60) groups. Clinical pregnancy rate (PR) and implantation rate (IR) were compared between the treatment and control groups. Uterine peristalsis frequency and serum OT and PGF2a levels of another group of 120 patients without endometriosis but with tubal factor infertility were compared with those of the endometriosis group. Written informed consent was obtained from each patient before inclusion. The study was approved by the institutional review board (Clinical Trial Registration Number: ChiCTRIOQ-14005715). There is no conflict of interest with any product used in this study. 2
Study Population Patients meeting the following inclusion criteria were prospectively recruited into the endometriosis group: [1] aged 20–45 years; [2] with baseline FSH <10 IU/L; [3] having endometriosis, as demonstrated by laparoscopy; [4] normal serum CA-125 level (<35 IU/L); [5] one or more day-5 good-quality embryo(s) available for transfer; and [6] fewer than three previous ET cycle failures. Most of these patients had minimal or mild endometriosis (n ¼ 82), and the rest had moderate or severe endometriosis (n ¼ 28), according to the revised classification of the American Society of Reproductive Medicine (formerly the American Fertility Society) (16). A total of 120 matched women without endometriosis but with tubal factor infertility were assigned to the tubal factor group. They were matched as follows: [1] women aged 20–45 years, with regular cycles (25– 35 days); [2] to enter IVF/intracytoplasmic sperm injection cycles of down-regulation with the long GnRH agonist protocol; [3] basic FSH level <10 IU/L; [4] basic antral follicle count level >5; [5] body mass index (BMI) %28 kg/m2; and [6] normal features of uterus and bilateral ovaries. The exclusion criteria for the endometriosis and tubal factor groups were as follows: [1] uterine anomaly; [2] uterine fibroids; [3] presence of hydrosalpinges; [4] fresh embryo transfer cycle; [5] patients received GnRH agonists or antagonists (GnRH analogous) treatment before frozen– thawed embryo transfer (FET) (if they received GnRH agonists or antagonists within 3 months or their ovaries were still suppressed with no regular menstruation); [6] endometrial thickness <8 mm; [7] day-3 ET; and [8] endocrine disorders (hyperthyroidism or hypothyroidism, hyperprolactinemia, premature ovarian failure, and polycystic ovary syndrome).
Cryopreservation Cycles The entire cohort of good-quality embryos was cryopreserved on day 5 and vitrified using an open system. In our center we use the Gardner blastocysts score. Blastocysts were given a numerical score from 1 to 6 on the basis of their degree of expansion and hatching status, as follows: 1, an early blastocyst with a blastocoel that is less than half of the volume of the embryo; 2, a blastocyst with a blastocoel that is half of or greater than half of the volume of the embryo; 3, a full blastocyst with a blastocoel completely filling the embryo; 4, an expanded blastocyst with a blastocoel volume larger than that of the early embryo, with a thinning zona; 5, a hatching blastocyst with the trophectoderm starting to herniate though the zona; and 6, a hatched blastocyst, in which the blastocyst has completely escaped from the zona. For blastocysts graded as 3–6 (i.e., full blastocysts onward), the development of the inner cell mass was assessed as follows: A, tightly packed, many cells; B, loosely grouped, several cells; or C, very few cells. The trophectoderm was assessed as follows: A, many cells forming a cohesive epithelium; B, few cells forming a loose epithelium; or C, very few large cells. By using this scoring system, good-quality embryo (R3BB) was selected for transfer. VOL. - NO. - / - 2016
Fertility and Sterility® For the natural FET cycles, development of the dominant follicle and endometrium was monitored from day 10 by regular transvaginal ultrasound, urine LH tests, and serum LH, E2, and P levels until ovulation. To prevent luteal phase defect, luteal phase support was provided from the day of ovulation by dydrogesterone tablets (10 mg three times daily; Duphaston, Abbott). For the artificial FET cycles, patients received E2 valerate (2 mg; Progynova, Bayer) from day 3 three times daily to prepare the endometrium for ET. Endometrial thickness was monitored by transvaginal ultrasound from day10; when the endometrium reached or exceeded 8 mm, P was given (60 mg IM once per day). On the ET day, the endometrial pattern was required to be type B, C, or B–C, which was classified according to Gonen and Casper and defined as follows (17): type B, an intermediate, isoechogenic pattern characterized by the same reflectivity compared with the surrounding myometrium, with a nonprominent or absent central echogenic line; type C, a multilayered ‘‘triple-line’’ endometrium consisting of prominent outer and central hyperechogenic lines and inner hypoechogenic or black regions.
Measurement of Uterine Contractions Three groups received a 4-minute ultrasound scan of the uterus in the sagittal plane using a 7.5-MHz transvaginal probe (Toshiba Nemio SSA-550A) at approximately 1 hour before ET by a single examiner. Measurement of uterine contractions was performed using the method described by Fanchin et al. (18) and Zhu et al. (19). Briefly, a video recorder was connected to the ultrasound to detect uterine contractions for 4 minutes. The records were analyzed at 4 regular speed using KMPlayer 3.9.1.130 (Pandora TV), and the frequency of uterine contractions was counted by two independent, experienced observers. Frequency of uterine contractions was calculated as the average of the observations by the two observers.
Blood Sampling and Hormone Testing Blood samples were drawn on the day of ET. Samples were centrifuged at 3,000 rpm for 10 minutes, and serum was stored at 80 C until testing for OT and PGF2a concentration by ELISA (Gen II ELISA, USCN). Estradiol and P in serum samples were determined with a radioimmunoassay kit (Beckman Coulter).
Atosiban Treatment A computer-generated system of sealed envelopes was used to randomly allocate the patients into either the control group (n ¼ 60) or the atosiban treatment group (n ¼ 60). Briefly, the research assistant used the software SPSS 16.0 to randomize the numbers 1 to 120 to ‘‘0’’ or ‘‘1,’’ whereby ‘‘0’’ means do not use atosiban and ‘‘1’’ means do use atosiban before ET. Then the numbers ‘‘0’’ and ‘‘1’’ were put into the sealed envelopes in randomized order. Each patient was given an envelope with either the numbers ‘‘0’’ or ‘‘1’’ in the envelope. Other people were blind to the envelopes. VOL. - NO. - / - 2016
Sixty patients in the treatment group were given atosiban (Tractocile, Ferring Pharmaceuticals) as an IV bolus of 6.75 mg at approximately 30 min before ET. Then ET was carried out. The laboratory staff and ET operator were blind to the groups.
Outcome Measures The primary outcome measures were clinical PR and IR. The secondary outcome measures included frequency of uterine contractions and serum concentrations of OT and PGF2a between the endometriosis and tubal factor groups. The IR was defined as the number of gestational sacs per number of embryos transferred. The PR was defined as the presence of one or more gestational sacs at 3 weeks after a positive hCG test with heartbeat. Miscarriage was defined as a loss of a clinical pregnancy before the 13 weeks’ of gestation.
Statistical Analysis Sample size was estimated to be a minimum of 58 women per study group, based on a minimum absolute difference of 25% between treatments. Alpha was set at 0.05 and b at 0.20. Statistical Package for Social Sciences version 16.0 (SPSS) was used for data analysis. Fisher's exact test was used for categorical variables. Quantitative variables were presented as mean SD and analyzed with Student's t test. Data for serum OT and PGF2a levels were transformed into normal distribution using the natural logarithms before statistical analysis. Logistic regression analysis was used to analyze factors predicting clinical pregnancy. A P value of < .05 was defined as statistically significant.
RESULTS Between December 2014 and July 2015, a total of 143 patients with endometriosis infertility were screened at the Assisted Reproductive Center, The Affiliated Hospital of Anhui Medical University. Of them, 120 patients were recruited and randomized: 60 in the atosiban group and 60 in the control group. Another 120 patients without endometriosis but with tubal factor infertility undergoing FET cycle were matched into the tubal factor group (Fig. 1). Baseline characteristics of women in the endometriosis group and the tubal factor group had no significant differences. The serum E2 and P levels were also comparable between the two groups. The frequency of uterine contractions and serum LogOT and LogPFG2a levels in the endometriosis group (2.5 1.2, 1.89 0.33 ng/L, and 2.83 0.34 ng/L, respectively) were all significantly higher than in the tubal factor group (1.8 1.0, 1.66 0.32 ng/L, and 2.36 0.35 ng/L, respectively) (Table 1). Clinical characteristics of the control and treatment groups are summarized in Table 2. Both of the groups were homogeneous in terms of age, length of infertility, BMI, endometrial thickness on the ET day, or the number of embryos transferred (P>.05). Additionally, no significant differences were detected in serum CA-125, E2, P, LogOT, and LogPGF2a concentrations and frequency of uterine contractions. 3
ORIGINAL ARTICLE: ENDOMETRIOSIS
FIGURE 1
Flow chart. He. Atosiban treatment in EMs under FET. Fertil Steril 2016.
After ET, statistical analyses of the IR, PR, and miscarriage rate of patients were carried out; results are shown in Table 3. In the atosiban treatment group, the clinical PR per cycle and the IR were 58.3% and 41.0%, respectively, which were significantly higher than the rates in the control group (38.3% and 23.4%, respectively; odds ratio 2.25, 95% confidence interval [CI] 1.08–4.68; P¼ .044). The miscarriage rate (8.6% vs. 8.7%, P¼1.000), twin PR (22.9% vs. 21.7%, P¼1.000) and triplet PR (8.6% vs. 4.3%, P¼1.000) did not differ in the endometriosis group with and without atosiban treatment. Binary logistic regression was used to analyze the prediction for clinical pregnancy by uterine contraction, atosiban treatment, cause of infertility, and serum OT and PGF2a. Atosiban administration was positively related [Exp(B) 1.874, 95% CI 1.067–3.291; P¼ .029) and uterine contractions were inversely related to the clinical pregnancy rate [Exp(B) 0.584, 95% CI 0.429–0.795; P¼ .001).
DISCUSSION This study shows higher rates of clinical pregnancy and implantation with atosiban treatment in patients with endometriosis undergoing FET. Significantly higher serum OT and PGF2a levels and uterine contractions in the endometriosis group were also observed. To the best of our knowledge this is the first study to date that focused on the use of atosiban 4
in endometriosis for priming the uterus to improve the pregnancy rate after FET. The cause of infertility associated with endometriosis remains elusive, with current findings suggesting a multifactorial mechanism (20–22). It has been reported that patients with endometriosis displayed a dramatic increase in uterine contractions, with uterine hyper- and dysperistalsis (8). In our study we measured the uterine contractions in the implantation window of endometriosis and tubal factor patients; we defined hyperperistalsis as more than two waves per minute, according to our study experience about uterine contractions at our center, and dysperistalsis referred to some of the contractions originating in the middle portion of the uterus and spreading simultaneously to the fundus and the cervix. Other contractions started simultaneously at different sites, creating a convulsive appearance of uterine activity, whereas some vanished before they had reached the fundal part of the uterus. Thus the contractile activity of the uterus displayed the characteristics of dysperistalsis (8). It is tempting to speculate that OT and prostaglandins act as mediators in this system of coordinated uterine contractions (23, 24). Whether this finding is due to a hyperactivated inflammatory response or a hyperactivated OT/OTR system within the epithelium remains to be elucidated (25). VOL. - NO. - / - 2016
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TABLE 1 Comparison of demographic characteristics and uterine contractions between the endometriosis and the tubal factor groups. Characteristic
Endometriosis group (n [ 120)
Tubal factor group (n [ 120)
31.14 4.19 20.81 2.44 3.81 2.71 10.89 1.77 776.83 585.56 68.71 30.63
30.28 3.95 21.34 2.10 3.56 2.10 10.56 1.71 773.26 539.96 63.68 31.37
64 (53.3) 56 (46.7) 71 (59.2) 2.4 1.0 1.94 0.37 2.85 0.39 49 (40.8) 2.7 1.4 1.82 0.25 2.80 0.26 1.89 0.33 2.83 0.34 2.5 1.2
57 (47.5) 63 (52.5) 70 (58.3) 1.8 1.0 1.65 0.30 2.38 0.32 50 (41.7) 1.8 1.0 1.68 0.35 2.35 0.40 1.66 0.32 2.36 0.35 1.8 1.0
Age (y) BMI (kg/m2) Infertility duration (y) Endometrial thickness (mm) E2 (pmol/L) P (nmol/L) Cycle number, n (%) First cycle Second cycle Nature FET cycle, n (%) UC (waves per minute) LogOT (ng/L) LogPGF2a (ng/L) Artificial FET cycle, n (%) UC (waves per minute) LogOT (ng/L) LogPGF2a (ng/L) LogOT (ng/L) LogPGF2a (ng/L) UC (waves per minute)
P value .104 .071 .511 .144 .972 .376 .366 .366 1.000 < .01 < .01 < .01 1.000 < .01 .025 < .01 < .01 < .01 < .01
Note: Values are mean SD unless otherwise noted. FET ¼ frozen–thawed embryo transfer; UC ¼ uterine contractions. He. Atosiban treatment in EMs under FET. Fertil Steril 2016.
Previously, the presence of OTR messenger RNA in human ovarian endometriotic cysts has been demonstrated (26). Evidence also shows that OT receptor is expressed in smooth muscle cells and epithelial cells of peritoneal endometriotic lesions and ovarian endometriotic cysts (13). These findings suggest that the inhibition of OTR by specific inhibitors might be a useful approach for the treatment of endometriosis. Asselin et al. (27) found that OT stimulated the production of PGF2a and PGE2 in cultured endometrial epithelial cells; OT also stimulates the production of PGF2a in bovine endometrial cells (28). The increased production of PGF2a can be a coactivator of nociceptors and a pain mediator, which further increase PGE2 and its own production in an autocrine/paracrine manner, causing dysmenorrhea and the development of endometriosis (29). However, there are
no studies on serum OT and PGF2a levels in patients with endometriosis. Common medical therapies used to treat endometriosis are hormonal medications and include combined oral contraceptives, progestins, danazol, and GnRH analogous. Although these medications may help to treat pain, they have shown no benefit in the treatment of endometriosis-associated infertility, often need long treatment time, and cause many side effects. The ideal uterus environment of patients is a key factor for the success of ET, including appropriate endometrial status, adequate endometrial perfusion, and absence of excessive uterine contractions; however, the above treatments have little benefit in improving the poor endometriosis uterine environment. It has been reported that there is evidence that GnRH agonists increase IVF pregnancy rates in stage 3 and 4 endometriosis patients when given 6–12 weeks before the
TABLE 2 Clinical data of the control and atosiban treatment groups in patients with endometriosis. Characteristic Age (y) BMI (kg/m2) Infertility duration (y) Endometrial thickness (mm) No. of embryos transferred CA125 (IU/L) E2 (pmol/L) P (nmol/L) LogOT(ng/L) LogPGF2a (ng/L) UC (waves per minute)
Control group (n [ 60)
Atosiban group (n [ 60)
P value
31.27 4.48 20.41 2.12 3.85 2.48 10.95 1.99 2.13 0.54 16.04 5.94 775.04 560.85 66.19 30.97 1.90 0.34 2.87 2.82 2.6 1.3
31.02 3.90 21.21 2.69 3.76 2.93 10.83 1.54 2.03 0.41 17.46 6.88 778.13 391.32 59.37 28.39 1.88 0.33 2.79 0.40 2.4 1.1
.745 .074 .856 .709 .253 .231 .961 .077 .801 .189 .455
Note: Values are mean SD. UC ¼ uterine contractions. He. Atosiban treatment in EMs under FET. Fertil Steril 2016.
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ORIGINAL ARTICLE: ENDOMETRIOSIS
TABLE 3 Frozen–thawed embryo transfer outcomes in the control and atosiban treatment groups in patients with endometriosis. Outcome
Control group (n [ 60)
Atosiban group (n [ 60)
P value
Clinical PR IR Miscarriage rate Twin PR Triplet PR
23/60 (38.3) 30/128 (23.4) 2/23 (8.7) 5/23 (21.7) 1/23 (4.3)
35/60 (58.3) 50/122 (41.0) 3/35 (8.6) 8/35 (22.9) 3/35 (8.6)
.044 .004 1.000 1.000 1.000
Note: Values are number (percentage). He. Atosiban treatment in EMs under FET. Fertil Steril 2016.
procedure (30); in contrast, patients with stage 2 endometriosis did not benefit uniquely from this treatment. Oxytocin receptor antagonist can compete with OT of OTR in uterine smooth muscle cells, decidual cells, and fetal membrane and inhibit OT-induced PGF2a and uterine activity. Currently, only atosiban, a combined OT/vasopressin V1A antagonist, has been registered for human use with minimal side effects (31). No side effects of atosiban in patients were encountered in our study. Atosiban was found not only to directly stop contractions and decrease release of PGF2a in human uterine smooth muscle cells but also preferentially to relax uterine arteries in near-term pregnant rats (32), which enriches uterine blood supply and supports embryo implantation. Thus, this treatment may show better clinical efficacy than other approaches and provide a specific treatment for the improvement of uterine receptivity (7). Although there are inconsistent results regarding whether the serum E2 level had an influence on uterine contractions, it is confirmed that the wave frequency is negatively correlated with serum P (33, 34). The Fujimoto group previously reported that infertile Asian women have peak serum E2 concentrations that are 15% higher than in white women when undergoing gonadotropin stimulation, and that infertile Asian women have lower PRs and IRs, which may be linked to different E2 metabolism (35, 36). In our study, serum concentrations of E2 in women with endometriosis did not differ from those in tubal factor women, so it might not affect FET outcomes in the present study. Additionally, because enough P was supported before ET, there were also no differences in the serum P level between the endometriosis and the tubal factor groups. It is intriguing to consider the locally elevated estrogen concentrations as a consequence of the pathologic expression of P450 aromatase and up-regulated OT/OTR system (37–39). The OT/OTR/PGF2a/P450 aromatase system may be the key event as a feed-forward system on the level of both the endometrium and the endometriotic lesions and increased production of endometrial OT, which influences uterine peristalsis in patients with endometriosis (25). In our study we also noticed that women with endometriosis displayed a marked uterine hyperperistalsis, which differed significantly from the peristalsis of the controls during the luteal phases. Uterine hyperperistalsis and dysperistalsis are considered to be responsible for both reduced fertility 6
and the development of endometriosis. Uterine hyper- and dysperistalsis enhance the tubal transport of endometrial tissue into the peritoneal cavity and may, in addition, promote the detachment of endometrial cells from the eutopic endometrium (8). This process may start from the later stages of menstruation (8) and continue throughout the entire cycle, which might contribute to the development of infertility and endometriosis. It is identified that the clinical PR was the highest when uterine contractions were <2.0 waves per minute, and the rate decreased with an increasing wave frequency thereafter (40). This study's limitations included no placebo group and no measurement of uterine contractions after atosiban administered, owing to difficulties in obtaining patients' consent for repeated transvaginal ultrasound. However, previous studies have confirmed effective reduction of uterine contractility by atosiban (7, 41). Indeed, the absence of a placebo group in our present study caused the bias that the psychological effects might contribute to the improvement of PR and IR in endometriosis besides pharmacological effects of atosiban. More comprehensive study is needed to fully elucidate the mechanism of action and clinical value of atosiban in this new indication. In conclusion, application of atosiban in patients with endometriosis improves the clinical PR and IR. The high level of serum OT level is closely associated with the stimulation of the secretion of PGF2a in endometriosis and contributes to a significantly higher frequency of uterine contractions, which might result in an unstable uterine environment in women with endometriosis. Atosiban may constitute a new treatment opportunity in endometriosis-associated infertility during ET procedures.
REFERENCES 1. 2. 3. 4.
5. 6. 7. 8.
9.
10.
11.
Giudice LC, Kao LC. Endometriosis. Lancet 2004;364:1789–99. Taylor RN, Lebovic DI, Mueller MD. Angiogenic factors in endometriosis. Ann N Y Acad Sci 2002;955:89–100. discussion 18, 396–406. Krikun G, Lockwood CJ, Paidas MJ. Tissue factor and the endometrium: from physiology to pathology. Thromb Res 2009;124:393–6. Macer ML, Taylor HS. Endometriosis and infertility: a review of the pathogenesis and treatment of endometriosis-associated infertility. Obstet Gynecol Clin North Am 2012;39:535–49. Surrey ES. Endometriosis-related infertility: the role of the assisted reproductive technologies. Biomed Res Int 2015;2015:482959. Barnhart K, Dunsmoor-Su R, Coutifaris C. Effect of endometriosis on in vitro fertilization. Fertil Steril 2002;77:1148–55. Pierzynski P, Reinheimer TM, Kuczynski W. Oxytocin antagonists may improve infertility treatment. Fertil Steril 2007;88:213.e19–22. Leyendecker G, Kunz G, Wildt L, Beil D, Deininger H. Uterine hyperperistalsis and dysperistalsis as dysfunctions of the mechanism of rapid sperm transport in patients with endometriosis and infertility. Hum Reprod 1996;11: 1542–51. Defendini R, Zimmerman EA. The magnocellular neurosecretory system of the mammalian hypothalamus. Res Publ Assoc Res Nerv Ment Dis 1978; 56:137–54. Braileanu GT, Simasko SM, Hu J, Assiri A, Mirando MA. Effects of arginineand lysine-vasopressin on phospholipase C activity, intracellular calcium concentration and prostaglandin F2alpha secretion in pig endometrial cells. Reproduction 2001;121:605–12. Stormshak F. Biochemical and endocrine aspects of oxytocin production by the mammalian corpus luteum. Reprod Biol Endocrinol 2003;1:92. VOL. - NO. - / - 2016
Fertility and Sterility® 12.
13.
14.
15.
16. 17.
18.
19. 20. 21. 22. 23.
24.
25.
26.
27.
Steinwall M, Hansson S, Bossmar T, Larsson I, Pilka R, Akerlund M. Oxytocin mRNA content in the endometrium of non-pregnant women. BJOG 2004; 111:266–70. Mechsner S, Bartley J, Loddenkemper C, Salomon DS, Starzinski-Powitz A, Ebert AD. Oxytocin receptor expression in smooth muscle cells of peritoneal endometriotic lesions and ovarian endometriotic cysts. Fertil Steril 2005; 83(Suppl 1):1220–31. Vasicka A, Kumaresan P, Li C, Scheffs J. Immunologic and biologic activity of oxytocin in midtrimester pregnancy. Am J Obstet Gynecol 1977;127: 171–5. Simsek Y, Celik O, Karaer A, Gul M, Yilmaz E, Koc O, et al. Therapeutic efficiency of atosiban, an oxytocin receptor blocking agent in the treatment of experimental endometriosis. Arch Gynecol Obstet 2012;286:777–83. Revised American Fertility Society classification of endometriosis: 1985. Fertil Steril 1985;43:351–2. Gonen Y, Casper RF. Prediction of implantation by the sonographic appearance of the endometrium during controlled ovarian stimulation for in vitro fertilization (IVF). J In Vitro Fert Embryo Transf 1990;7:146–52. Fanchin R, Righini C, Olivennes F, Taylor S, de Ziegler D, Frydman R. Uterine contractions at the time of embryo transfer alter pregnancy rates after invitro fertilization. Hum Reprod 1998;13:1968–74. Zhu L, Xiao L, Che HS, Li YP, Liao JT. Uterine peristalsis exerts control over fluid migration after mock embryo transfer. Hum Reprod 2014;29:279–85. Practice Committee of the American Society for Reproductive Medicine. Endometriosis and infertility. Fertil Steril 2006;86:S156–60. de Ziegler D, Borghese B, Chapron C. Endometriosis and infertility: pathophysiology and management. Lancet 2010;376:730–8. Gryparis I, Nardo LG. Update in endometriosis and IVF. Minerva Ginecol 2011;63:571–6. Lefebvre DL, Farookhi R, Larcher A, Neculcea J, Zingg HH. Uterine oxytocin gene expression. I. Induction during pseudopregnancy and the estrous cycle. Endocrinology 1994;134:2556–61. Lefebvre DL, Farookhi R, Giaid A, Neculcea J, Zingg HH. Uterine oxytocin gene expression. II. Induction by exogenous steroid administration. Endocrinology 1994;134:2562–6. Leyendecker G, Kunz G, Noe M, Herbertz M, Mall G. Endometriosis: a dysfunction and disease of the archimetra. Hum Reprod Update 1998;4: 752–62. Mizumoto Y, Furuya K, Makimura N, Mitsui C, Seki K, Kimura T, et al. Gene expression of oxytocin receptor in human ectopic endometrial tissues. Adv Exp Med Biol 1995;395:491–3. Asselin E, Goff AK, Bergeron H, Fortier MA. Influence of sex steroids on the production of prostaglandins F2 alpha and E2 and response to oxytocin in
VOL. - NO. - / - 2016
28.
29. 30.
31.
32.
33.
34. 35.
36.
37. 38.
39.
40.
41.
cultured epithelial and stromal cells of the bovine endometrium. Biol Reprod 1996;54:371–9. Danet-Desnoyers G, Wetzels C, Thatcher WW. Natural and recombinant bovine interferon tau regulate basal and oxytocin-induced secretion of prostaglandins F2 alpha and E2 by epithelial cells and stromal cells in the endometrium. Reprod Fertil Dev 1994;6:193–202. Sales KJ, Jabbour HN. Cyclooxygenase enzymes and prostaglandins in pathology of the endometrium. Reproduction 2003;126:559–67. Rickes D, Nickel I, Kropf S, Kleinstein J. Increased pregnancy rates after ultralong postoperative therapy with gonadotropin-releasing hormone analogs in patients with endometriosis. Fertil Steril 2002;78:757–62. Husslein P, Quartarolo JP. Review of clinical experience with atosiban and the Tractocile Efficacy Assessment Survey in Europe (TREASURE) study protocol. Int J Clin Pract 2003;57:121–7. Vedernikov Y, Betancourt A, Shi SQ, Shi LL, Reinheimer T, Garfield RE. Oxytocin antagonistic effect of barusiban and atosiban in isolated uterine artery from late pregnant rats. J Soc Gynecol Invest 2006;13:192a. Fanchin R, Ayoubi JM, Olivennes F, Righini C, de Ziegler D, Frydman R. Hormonal influence on the uterine contractility during ovarian stimulation. Hum Reprod 2000;15(Suppl 1):90–100. Zhu L, Li Y, Xu A. Influence of controlled ovarian hyperstimulation on uterine peristalsis in infertile women. Hum Reprod 2012;27:2684–9. Purcell K, Schembri M, Frazier LM, Rall MJ, Shen S, Croughan M, et al. Asian ethnicity is associated with reduced pregnancy outcomes after assisted reproductive technology. Fertil Steril 2007;87:297–302. Huddleston HG, Rosen MP, Gibson M, Cedars MI, Fujimoto VY. Ethnic variation in estradiol metabolism in reproductive age Asian and white women treated with transdermal estradiol. Fertil Steril 2011;96:797–9. Noble LS, Simpson ER, Johns A, Bulun SE. Aromatase expression in endometriosis. J Clin Endocrinol Metab 1996;81:174–9. Noble LS, Takayama K, Zeitoun KM, Putman JM, Johns DA, Hinshelwood MM, et al. Prostaglandin E2 stimulates aromatase expression in endometriosis-derived stromal cells. J Clin Endocrinol Metab 1997;82: 600–6. Zingg HH, Rozen F, Chu K, Larcher A, Arslan A, Richard S, et al. Oxytocin and oxytocin receptor gene expression in the uterus. Recent Prog Horm Res 1995;50:255–73. Zhu L, Che HS, Xiao L, Li YP. Uterine peristalsis before embryo transfer affects the chance of clinical pregnancy in fresh and frozen-thawed embryo transfer cycles. Hum Reprod 2014;29:1238–43. Lan VT, Khang VN, Nhu GH, Tuong HM. Atosiban improves implantation and pregnancy rates in patients with repeated implantation failure. Reprod Biomed Online 2012;25:254–60.
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Administration of atosiban in patients with endometriosis undergoing frozen–thawed embryo transfer: a prospective, randomized study Ye He, M.D., Huan Wu, M.D., Xiaojin He, M.D., Ph.D, Qiong Xing, M.D., Ping Zhou, M.D., Yunxia Cao, M.D., Ph.D., and Zhaolian Wei, M.D., Ph.D. Department of Obstetrics and Gynecology, Reproductive Medicine Center, The First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China
Objective: To examine the effects of atosiban, given before transfer of frozen–thawed embryo to women with endometriosis (EMs). Design: A prospective, randomized, controlled clinical trial. Setting: University hospital and IVF center. Patient(s): One hundred twenty women with endometriosis undergoing frozen–thawed embryo transfer were randomly allocated into the atosiban treatment and the control groups. Another 120 women with infertility due to tubal factor were enrolled into a tubal factor group, to compare serum oxytocin (OT) and prostaglandin (PG)F2a levels and uterine contractions with the endometriosis group. Intervention(s): In the endometriosis treatment group, a single bolus (6.75 mg, 0.9 mL per vial) of atosiban was administrated before ET. Main Outcome Measure(s): Implantation rate and pregnancy rate. Result(s): Serum OT level (1.89 0.33 vs. 1.66 0.32 ng/L), PGF2a (2.83 0.34 vs. 2.36 0.35 ng/L) level, and uterine contractions (2.5 1.2 vs. 1.8 1.0 waves per minute) in the endometriosis group were all significantly higher than in the tubal factor group. The clinical pregnancy rate per cycle and implantation rate per transfer were 58.3% and 41.0%, respectively, in the atosiban treatment group, significantly higher than in the control group (38.3% and 23.4%, respectively). Conclusion(s): Women with endometriosis showed higher serum OT level, PGF2a level, and uterine contractions. Atosiban treatment before ET in endometriosis is effective in the priming of the uterus, suitable for embryo implantation. This is the first study to evaluate the effect of atosiban treatment in patients with endometriosis. Use your smartphone Clinical Trial Registration Number: ChiCTR-IOQ-14005715. (Fertil SterilÒ 2016;-:-–-. to scan this QR code Ó2016 by American Society for Reproductive Medicine.) and connect to the Key Words: Atosiban, clinical pregnancy rate, endometriosis, oxytocin, uterine contractility Discuss: You can discuss this article with its authors and with other ASRM members at http:// fertstertforum.com/hey-atosiban-endometriosis-fet/
E
ndometriosis is a benign gynecologic disorder characterized by the presence of endometrial tissue outside the uterus and is accompanied by pain and infertility (1). The disease affects approximately 10% of women of reproductive age and
20%–50% of infertile women (2, 3). In vitro fertilization is currently the most effective treatment for endometriosis-associated infertility (4), especially for those who have experienced surgical treatment but are still infertile. Although the issue of whether
Received November 5, 2015; revised April 2, 2016; accepted April 14, 2016. Y.H. has nothing to disclose. H.W. has nothing to disclose. X.H. has nothing to disclose. Q.X. has nothing to disclose. P.Z. has nothing to disclose. Y.C. has nothing to disclose. Z.W. has nothing to disclose. Reprint requests: Zhaolian Wei, M.D., Ph.D., The First Affiliated Hospital of Anhui Medical University, Department of Obstetrics and Gynecology, Reproductive Medicine Center, 218 Jixi Road, Hefei, People's Republic of China (E-mail: [email protected]). Fertility and Sterility® Vol. -, No. -, - 2016 0015-0282/$36.00 Copyright ©2016 American Society for Reproductive Medicine, Published by Elsevier Inc. http://dx.doi.org/10.1016/j.fertnstert.2016.04.019 VOL. - NO. - / - 2016
discussion forum for this article now.*
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the presence of endometriosis has a negative impact on the outcome of IVF has not been resolved (5), previous studies have shown that the pregnancy rate is reduced in infertile women with endometriosis undergoing IVF when compared with tubal factor infertility (6). The changed receptivity of the endometrium may account for this reduced performance. Ideal intrauterine conditions that enable implantation include appropriate endometrial states, sufficient endometrial perfusion, and absence of excessive uterine contractions (7). A significantly higher uterine contraction 1
ORIGINAL ARTICLE: ENDOMETRIOSIS frequency was found in women with endometriosis than in women without endometriosis (8), which may contribute to the development of endometriosis as well as to the reduced IVF success rate in women with endometriosis. Oxytocin (OT), a nonapeptide synthesized by neurons of the supraoptic nucleus and released from the posterior pituitary gland, has diverse effects on the female reproductive system (9). It is known to be a factor causing uterine contractions. It has also been shown in animal models that endometrial cells contain oxytocin receptors (OTRs) and that OT has the capacity to trigger the production of prostaglandin (PG)F2a from these cells (10, 11). Steinwall et al. (12) demonstrated that OT may be synthesized in the endometrium of nonpregnant women, particularly in the glandular epithelial cells. Hormone released from these sources may have a paracrine action on the uterus. Furthermore, Mechsner et al. (13) reported that OTRs are expressed in smooth muscle cells and in the epithelial cells of peritoneal endometriotic lesions and ovarian endometriotic cysts of premenopausal women, suggesting that OT might participate in the pathogenesis of endometriosis and contribute to infertility. It is well known that an increase of plasma OT levels in pregnant women stimulates uterine contractions (14). Thus, we speculate that a hyperactivated autocrine/paracrine OT/ OTR system in endometriosis may result in uterine hyperperistalsis and poor endometrial receptivity. The therapeutic efficiency of atosiban, an OTR antagonist, was confirmed in a report using endometriotic rat models in which the volumes of endometriotic implants and proliferating cell nuclear antigen expression levels were significantly reduced in the atosiban treatment group (15). On the basis of this background, we designed the present study to investigate the effect of atosiban used before ET in patients with endometriosis and analyze serum OT and PGF2a levels and uterine contractions in patients with endometriosis.
MATERIALS AND METHODS This was a randomized clinical trial for the first part described. The part comparing endometriosis patients with tubal factor patients was a prospective cohort study. The study was performed from December 2014 to July 2015. A total of 120 patients with endometriosis undergoing IVF/ET using cryopreserved embryos in the reproductive center of the First Affiliated Hospital of Anhui Medical University were randomized into treatment (n ¼ 60) and control (n ¼ 60) groups. Clinical pregnancy rate (PR) and implantation rate (IR) were compared between the treatment and control groups. Uterine peristalsis frequency and serum OT and PGF2a levels of another group of 120 patients without endometriosis but with tubal factor infertility were compared with those of the endometriosis group. Written informed consent was obtained from each patient before inclusion. The study was approved by the institutional review board (Clinical Trial Registration Number: ChiCTRIOQ-14005715). There is no conflict of interest with any product used in this study. 2
Study Population Patients meeting the following inclusion criteria were prospectively recruited into the endometriosis group: [1] aged 20–45 years; [2] with baseline FSH <10 IU/L; [3] having endometriosis, as demonstrated by laparoscopy; [4] normal serum CA-125 level (<35 IU/L); [5] one or more day-5 good-quality embryo(s) available for transfer; and [6] fewer than three previous ET cycle failures. Most of these patients had minimal or mild endometriosis (n ¼ 82), and the rest had moderate or severe endometriosis (n ¼ 28), according to the revised classification of the American Society of Reproductive Medicine (formerly the American Fertility Society) (16). A total of 120 matched women without endometriosis but with tubal factor infertility were assigned to the tubal factor group. They were matched as follows: [1] women aged 20–45 years, with regular cycles (25– 35 days); [2] to enter IVF/intracytoplasmic sperm injection cycles of down-regulation with the long GnRH agonist protocol; [3] basic FSH level <10 IU/L; [4] basic antral follicle count level >5; [5] body mass index (BMI) %28 kg/m2; and [6] normal features of uterus and bilateral ovaries. The exclusion criteria for the endometriosis and tubal factor groups were as follows: [1] uterine anomaly; [2] uterine fibroids; [3] presence of hydrosalpinges; [4] fresh embryo transfer cycle; [5] patients received GnRH agonists or antagonists (GnRH analogous) treatment before frozen– thawed embryo transfer (FET) (if they received GnRH agonists or antagonists within 3 months or their ovaries were still suppressed with no regular menstruation); [6] endometrial thickness <8 mm; [7] day-3 ET; and [8] endocrine disorders (hyperthyroidism or hypothyroidism, hyperprolactinemia, premature ovarian failure, and polycystic ovary syndrome).
Cryopreservation Cycles The entire cohort of good-quality embryos was cryopreserved on day 5 and vitrified using an open system. In our center we use the Gardner blastocysts score. Blastocysts were given a numerical score from 1 to 6 on the basis of their degree of expansion and hatching status, as follows: 1, an early blastocyst with a blastocoel that is less than half of the volume of the embryo; 2, a blastocyst with a blastocoel that is half of or greater than half of the volume of the embryo; 3, a full blastocyst with a blastocoel completely filling the embryo; 4, an expanded blastocyst with a blastocoel volume larger than that of the early embryo, with a thinning zona; 5, a hatching blastocyst with the trophectoderm starting to herniate though the zona; and 6, a hatched blastocyst, in which the blastocyst has completely escaped from the zona. For blastocysts graded as 3–6 (i.e., full blastocysts onward), the development of the inner cell mass was assessed as follows: A, tightly packed, many cells; B, loosely grouped, several cells; or C, very few cells. The trophectoderm was assessed as follows: A, many cells forming a cohesive epithelium; B, few cells forming a loose epithelium; or C, very few large cells. By using this scoring system, good-quality embryo (R3BB) was selected for transfer. VOL. - NO. - / - 2016
Fertility and Sterility® For the natural FET cycles, development of the dominant follicle and endometrium was monitored from day 10 by regular transvaginal ultrasound, urine LH tests, and serum LH, E2, and P levels until ovulation. To prevent luteal phase defect, luteal phase support was provided from the day of ovulation by dydrogesterone tablets (10 mg three times daily; Duphaston, Abbott). For the artificial FET cycles, patients received E2 valerate (2 mg; Progynova, Bayer) from day 3 three times daily to prepare the endometrium for ET. Endometrial thickness was monitored by transvaginal ultrasound from day10; when the endometrium reached or exceeded 8 mm, P was given (60 mg IM once per day). On the ET day, the endometrial pattern was required to be type B, C, or B–C, which was classified according to Gonen and Casper and defined as follows (17): type B, an intermediate, isoechogenic pattern characterized by the same reflectivity compared with the surrounding myometrium, with a nonprominent or absent central echogenic line; type C, a multilayered ‘‘triple-line’’ endometrium consisting of prominent outer and central hyperechogenic lines and inner hypoechogenic or black regions.
Measurement of Uterine Contractions Three groups received a 4-minute ultrasound scan of the uterus in the sagittal plane using a 7.5-MHz transvaginal probe (Toshiba Nemio SSA-550A) at approximately 1 hour before ET by a single examiner. Measurement of uterine contractions was performed using the method described by Fanchin et al. (18) and Zhu et al. (19). Briefly, a video recorder was connected to the ultrasound to detect uterine contractions for 4 minutes. The records were analyzed at 4 regular speed using KMPlayer 3.9.1.130 (Pandora TV), and the frequency of uterine contractions was counted by two independent, experienced observers. Frequency of uterine contractions was calculated as the average of the observations by the two observers.
Blood Sampling and Hormone Testing Blood samples were drawn on the day of ET. Samples were centrifuged at 3,000 rpm for 10 minutes, and serum was stored at 80 C until testing for OT and PGF2a concentration by ELISA (Gen II ELISA, USCN). Estradiol and P in serum samples were determined with a radioimmunoassay kit (Beckman Coulter).
Atosiban Treatment A computer-generated system of sealed envelopes was used to randomly allocate the patients into either the control group (n ¼ 60) or the atosiban treatment group (n ¼ 60). Briefly, the research assistant used the software SPSS 16.0 to randomize the numbers 1 to 120 to ‘‘0’’ or ‘‘1,’’ whereby ‘‘0’’ means do not use atosiban and ‘‘1’’ means do use atosiban before ET. Then the numbers ‘‘0’’ and ‘‘1’’ were put into the sealed envelopes in randomized order. Each patient was given an envelope with either the numbers ‘‘0’’ or ‘‘1’’ in the envelope. Other people were blind to the envelopes. VOL. - NO. - / - 2016
Sixty patients in the treatment group were given atosiban (Tractocile, Ferring Pharmaceuticals) as an IV bolus of 6.75 mg at approximately 30 min before ET. Then ET was carried out. The laboratory staff and ET operator were blind to the groups.
Outcome Measures The primary outcome measures were clinical PR and IR. The secondary outcome measures included frequency of uterine contractions and serum concentrations of OT and PGF2a between the endometriosis and tubal factor groups. The IR was defined as the number of gestational sacs per number of embryos transferred. The PR was defined as the presence of one or more gestational sacs at 3 weeks after a positive hCG test with heartbeat. Miscarriage was defined as a loss of a clinical pregnancy before the 13 weeks’ of gestation.
Statistical Analysis Sample size was estimated to be a minimum of 58 women per study group, based on a minimum absolute difference of 25% between treatments. Alpha was set at 0.05 and b at 0.20. Statistical Package for Social Sciences version 16.0 (SPSS) was used for data analysis. Fisher's exact test was used for categorical variables. Quantitative variables were presented as mean SD and analyzed with Student's t test. Data for serum OT and PGF2a levels were transformed into normal distribution using the natural logarithms before statistical analysis. Logistic regression analysis was used to analyze factors predicting clinical pregnancy. A P value of < .05 was defined as statistically significant.
RESULTS Between December 2014 and July 2015, a total of 143 patients with endometriosis infertility were screened at the Assisted Reproductive Center, The Affiliated Hospital of Anhui Medical University. Of them, 120 patients were recruited and randomized: 60 in the atosiban group and 60 in the control group. Another 120 patients without endometriosis but with tubal factor infertility undergoing FET cycle were matched into the tubal factor group (Fig. 1). Baseline characteristics of women in the endometriosis group and the tubal factor group had no significant differences. The serum E2 and P levels were also comparable between the two groups. The frequency of uterine contractions and serum LogOT and LogPFG2a levels in the endometriosis group (2.5 1.2, 1.89 0.33 ng/L, and 2.83 0.34 ng/L, respectively) were all significantly higher than in the tubal factor group (1.8 1.0, 1.66 0.32 ng/L, and 2.36 0.35 ng/L, respectively) (Table 1). Clinical characteristics of the control and treatment groups are summarized in Table 2. Both of the groups were homogeneous in terms of age, length of infertility, BMI, endometrial thickness on the ET day, or the number of embryos transferred (P>.05). Additionally, no significant differences were detected in serum CA-125, E2, P, LogOT, and LogPGF2a concentrations and frequency of uterine contractions. 3
ORIGINAL ARTICLE: ENDOMETRIOSIS
FIGURE 1
Flow chart. He. Atosiban treatment in EMs under FET. Fertil Steril 2016.
After ET, statistical analyses of the IR, PR, and miscarriage rate of patients were carried out; results are shown in Table 3. In the atosiban treatment group, the clinical PR per cycle and the IR were 58.3% and 41.0%, respectively, which were significantly higher than the rates in the control group (38.3% and 23.4%, respectively; odds ratio 2.25, 95% confidence interval [CI] 1.08–4.68; P¼ .044). The miscarriage rate (8.6% vs. 8.7%, P¼1.000), twin PR (22.9% vs. 21.7%, P¼1.000) and triplet PR (8.6% vs. 4.3%, P¼1.000) did not differ in the endometriosis group with and without atosiban treatment. Binary logistic regression was used to analyze the prediction for clinical pregnancy by uterine contraction, atosiban treatment, cause of infertility, and serum OT and PGF2a. Atosiban administration was positively related [Exp(B) 1.874, 95% CI 1.067–3.291; P¼ .029) and uterine contractions were inversely related to the clinical pregnancy rate [Exp(B) 0.584, 95% CI 0.429–0.795; P¼ .001).
DISCUSSION This study shows higher rates of clinical pregnancy and implantation with atosiban treatment in patients with endometriosis undergoing FET. Significantly higher serum OT and PGF2a levels and uterine contractions in the endometriosis group were also observed. To the best of our knowledge this is the first study to date that focused on the use of atosiban 4
in endometriosis for priming the uterus to improve the pregnancy rate after FET. The cause of infertility associated with endometriosis remains elusive, with current findings suggesting a multifactorial mechanism (20–22). It has been reported that patients with endometriosis displayed a dramatic increase in uterine contractions, with uterine hyper- and dysperistalsis (8). In our study we measured the uterine contractions in the implantation window of endometriosis and tubal factor patients; we defined hyperperistalsis as more than two waves per minute, according to our study experience about uterine contractions at our center, and dysperistalsis referred to some of the contractions originating in the middle portion of the uterus and spreading simultaneously to the fundus and the cervix. Other contractions started simultaneously at different sites, creating a convulsive appearance of uterine activity, whereas some vanished before they had reached the fundal part of the uterus. Thus the contractile activity of the uterus displayed the characteristics of dysperistalsis (8). It is tempting to speculate that OT and prostaglandins act as mediators in this system of coordinated uterine contractions (23, 24). Whether this finding is due to a hyperactivated inflammatory response or a hyperactivated OT/OTR system within the epithelium remains to be elucidated (25). VOL. - NO. - / - 2016
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TABLE 1 Comparison of demographic characteristics and uterine contractions between the endometriosis and the tubal factor groups. Characteristic
Endometriosis group (n [ 120)
Tubal factor group (n [ 120)
31.14 4.19 20.81 2.44 3.81 2.71 10.89 1.77 776.83 585.56 68.71 30.63
30.28 3.95 21.34 2.10 3.56 2.10 10.56 1.71 773.26 539.96 63.68 31.37
64 (53.3) 56 (46.7) 71 (59.2) 2.4 1.0 1.94 0.37 2.85 0.39 49 (40.8) 2.7 1.4 1.82 0.25 2.80 0.26 1.89 0.33 2.83 0.34 2.5 1.2
57 (47.5) 63 (52.5) 70 (58.3) 1.8 1.0 1.65 0.30 2.38 0.32 50 (41.7) 1.8 1.0 1.68 0.35 2.35 0.40 1.66 0.32 2.36 0.35 1.8 1.0
Age (y) BMI (kg/m2) Infertility duration (y) Endometrial thickness (mm) E2 (pmol/L) P (nmol/L) Cycle number, n (%) First cycle Second cycle Nature FET cycle, n (%) UC (waves per minute) LogOT (ng/L) LogPGF2a (ng/L) Artificial FET cycle, n (%) UC (waves per minute) LogOT (ng/L) LogPGF2a (ng/L) LogOT (ng/L) LogPGF2a (ng/L) UC (waves per minute)
P value .104 .071 .511 .144 .972 .376 .366 .366 1.000 < .01 < .01 < .01 1.000 < .01 .025 < .01 < .01 < .01 < .01
Note: Values are mean SD unless otherwise noted. FET ¼ frozen–thawed embryo transfer; UC ¼ uterine contractions. He. Atosiban treatment in EMs under FET. Fertil Steril 2016.
Previously, the presence of OTR messenger RNA in human ovarian endometriotic cysts has been demonstrated (26). Evidence also shows that OT receptor is expressed in smooth muscle cells and epithelial cells of peritoneal endometriotic lesions and ovarian endometriotic cysts (13). These findings suggest that the inhibition of OTR by specific inhibitors might be a useful approach for the treatment of endometriosis. Asselin et al. (27) found that OT stimulated the production of PGF2a and PGE2 in cultured endometrial epithelial cells; OT also stimulates the production of PGF2a in bovine endometrial cells (28). The increased production of PGF2a can be a coactivator of nociceptors and a pain mediator, which further increase PGE2 and its own production in an autocrine/paracrine manner, causing dysmenorrhea and the development of endometriosis (29). However, there are
no studies on serum OT and PGF2a levels in patients with endometriosis. Common medical therapies used to treat endometriosis are hormonal medications and include combined oral contraceptives, progestins, danazol, and GnRH analogous. Although these medications may help to treat pain, they have shown no benefit in the treatment of endometriosis-associated infertility, often need long treatment time, and cause many side effects. The ideal uterus environment of patients is a key factor for the success of ET, including appropriate endometrial status, adequate endometrial perfusion, and absence of excessive uterine contractions; however, the above treatments have little benefit in improving the poor endometriosis uterine environment. It has been reported that there is evidence that GnRH agonists increase IVF pregnancy rates in stage 3 and 4 endometriosis patients when given 6–12 weeks before the
TABLE 2 Clinical data of the control and atosiban treatment groups in patients with endometriosis. Characteristic Age (y) BMI (kg/m2) Infertility duration (y) Endometrial thickness (mm) No. of embryos transferred CA125 (IU/L) E2 (pmol/L) P (nmol/L) LogOT(ng/L) LogPGF2a (ng/L) UC (waves per minute)
Control group (n [ 60)
Atosiban group (n [ 60)
P value
31.27 4.48 20.41 2.12 3.85 2.48 10.95 1.99 2.13 0.54 16.04 5.94 775.04 560.85 66.19 30.97 1.90 0.34 2.87 2.82 2.6 1.3
31.02 3.90 21.21 2.69 3.76 2.93 10.83 1.54 2.03 0.41 17.46 6.88 778.13 391.32 59.37 28.39 1.88 0.33 2.79 0.40 2.4 1.1
.745 .074 .856 .709 .253 .231 .961 .077 .801 .189 .455
Note: Values are mean SD. UC ¼ uterine contractions. He. Atosiban treatment in EMs under FET. Fertil Steril 2016.
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ORIGINAL ARTICLE: ENDOMETRIOSIS
TABLE 3 Frozen–thawed embryo transfer outcomes in the control and atosiban treatment groups in patients with endometriosis. Outcome
Control group (n [ 60)
Atosiban group (n [ 60)
P value
Clinical PR IR Miscarriage rate Twin PR Triplet PR
23/60 (38.3) 30/128 (23.4) 2/23 (8.7) 5/23 (21.7) 1/23 (4.3)
35/60 (58.3) 50/122 (41.0) 3/35 (8.6) 8/35 (22.9) 3/35 (8.6)
.044 .004 1.000 1.000 1.000
Note: Values are number (percentage). He. Atosiban treatment in EMs under FET. Fertil Steril 2016.
procedure (30); in contrast, patients with stage 2 endometriosis did not benefit uniquely from this treatment. Oxytocin receptor antagonist can compete with OT of OTR in uterine smooth muscle cells, decidual cells, and fetal membrane and inhibit OT-induced PGF2a and uterine activity. Currently, only atosiban, a combined OT/vasopressin V1A antagonist, has been registered for human use with minimal side effects (31). No side effects of atosiban in patients were encountered in our study. Atosiban was found not only to directly stop contractions and decrease release of PGF2a in human uterine smooth muscle cells but also preferentially to relax uterine arteries in near-term pregnant rats (32), which enriches uterine blood supply and supports embryo implantation. Thus, this treatment may show better clinical efficacy than other approaches and provide a specific treatment for the improvement of uterine receptivity (7). Although there are inconsistent results regarding whether the serum E2 level had an influence on uterine contractions, it is confirmed that the wave frequency is negatively correlated with serum P (33, 34). The Fujimoto group previously reported that infertile Asian women have peak serum E2 concentrations that are 15% higher than in white women when undergoing gonadotropin stimulation, and that infertile Asian women have lower PRs and IRs, which may be linked to different E2 metabolism (35, 36). In our study, serum concentrations of E2 in women with endometriosis did not differ from those in tubal factor women, so it might not affect FET outcomes in the present study. Additionally, because enough P was supported before ET, there were also no differences in the serum P level between the endometriosis and the tubal factor groups. It is intriguing to consider the locally elevated estrogen concentrations as a consequence of the pathologic expression of P450 aromatase and up-regulated OT/OTR system (37–39). The OT/OTR/PGF2a/P450 aromatase system may be the key event as a feed-forward system on the level of both the endometrium and the endometriotic lesions and increased production of endometrial OT, which influences uterine peristalsis in patients with endometriosis (25). In our study we also noticed that women with endometriosis displayed a marked uterine hyperperistalsis, which differed significantly from the peristalsis of the controls during the luteal phases. Uterine hyperperistalsis and dysperistalsis are considered to be responsible for both reduced fertility 6
and the development of endometriosis. Uterine hyper- and dysperistalsis enhance the tubal transport of endometrial tissue into the peritoneal cavity and may, in addition, promote the detachment of endometrial cells from the eutopic endometrium (8). This process may start from the later stages of menstruation (8) and continue throughout the entire cycle, which might contribute to the development of infertility and endometriosis. It is identified that the clinical PR was the highest when uterine contractions were <2.0 waves per minute, and the rate decreased with an increasing wave frequency thereafter (40). This study's limitations included no placebo group and no measurement of uterine contractions after atosiban administered, owing to difficulties in obtaining patients' consent for repeated transvaginal ultrasound. However, previous studies have confirmed effective reduction of uterine contractility by atosiban (7, 41). Indeed, the absence of a placebo group in our present study caused the bias that the psychological effects might contribute to the improvement of PR and IR in endometriosis besides pharmacological effects of atosiban. More comprehensive study is needed to fully elucidate the mechanism of action and clinical value of atosiban in this new indication. In conclusion, application of atosiban in patients with endometriosis improves the clinical PR and IR. The high level of serum OT level is closely associated with the stimulation of the secretion of PGF2a in endometriosis and contributes to a significantly higher frequency of uterine contractions, which might result in an unstable uterine environment in women with endometriosis. Atosiban may constitute a new treatment opportunity in endometriosis-associated infertility during ET procedures.
REFERENCES 1. 2. 3. 4.
5. 6. 7. 8.
9.
10.
11.
Giudice LC, Kao LC. Endometriosis. Lancet 2004;364:1789–99. Taylor RN, Lebovic DI, Mueller MD. Angiogenic factors in endometriosis. Ann N Y Acad Sci 2002;955:89–100. discussion 18, 396–406. Krikun G, Lockwood CJ, Paidas MJ. Tissue factor and the endometrium: from physiology to pathology. Thromb Res 2009;124:393–6. Macer ML, Taylor HS. Endometriosis and infertility: a review of the pathogenesis and treatment of endometriosis-associated infertility. Obstet Gynecol Clin North Am 2012;39:535–49. Surrey ES. Endometriosis-related infertility: the role of the assisted reproductive technologies. Biomed Res Int 2015;2015:482959. Barnhart K, Dunsmoor-Su R, Coutifaris C. Effect of endometriosis on in vitro fertilization. Fertil Steril 2002;77:1148–55. Pierzynski P, Reinheimer TM, Kuczynski W. Oxytocin antagonists may improve infertility treatment. Fertil Steril 2007;88:213.e19–22. Leyendecker G, Kunz G, Wildt L, Beil D, Deininger H. Uterine hyperperistalsis and dysperistalsis as dysfunctions of the mechanism of rapid sperm transport in patients with endometriosis and infertility. Hum Reprod 1996;11: 1542–51. Defendini R, Zimmerman EA. The magnocellular neurosecretory system of the mammalian hypothalamus. Res Publ Assoc Res Nerv Ment Dis 1978; 56:137–54. Braileanu GT, Simasko SM, Hu J, Assiri A, Mirando MA. Effects of arginineand lysine-vasopressin on phospholipase C activity, intracellular calcium concentration and prostaglandin F2alpha secretion in pig endometrial cells. Reproduction 2001;121:605–12. Stormshak F. Biochemical and endocrine aspects of oxytocin production by the mammalian corpus luteum. Reprod Biol Endocrinol 2003;1:92. VOL. - NO. - / - 2016
Fertility and Sterility® 12.
13.
14.
15.
16. 17.
18.
19. 20. 21. 22. 23.
24.
25.
26.
27.
Steinwall M, Hansson S, Bossmar T, Larsson I, Pilka R, Akerlund M. Oxytocin mRNA content in the endometrium of non-pregnant women. BJOG 2004; 111:266–70. Mechsner S, Bartley J, Loddenkemper C, Salomon DS, Starzinski-Powitz A, Ebert AD. Oxytocin receptor expression in smooth muscle cells of peritoneal endometriotic lesions and ovarian endometriotic cysts. Fertil Steril 2005; 83(Suppl 1):1220–31. Vasicka A, Kumaresan P, Li C, Scheffs J. Immunologic and biologic activity of oxytocin in midtrimester pregnancy. Am J Obstet Gynecol 1977;127: 171–5. Simsek Y, Celik O, Karaer A, Gul M, Yilmaz E, Koc O, et al. Therapeutic efficiency of atosiban, an oxytocin receptor blocking agent in the treatment of experimental endometriosis. Arch Gynecol Obstet 2012;286:777–83. Revised American Fertility Society classification of endometriosis: 1985. Fertil Steril 1985;43:351–2. Gonen Y, Casper RF. Prediction of implantation by the sonographic appearance of the endometrium during controlled ovarian stimulation for in vitro fertilization (IVF). J In Vitro Fert Embryo Transf 1990;7:146–52. Fanchin R, Righini C, Olivennes F, Taylor S, de Ziegler D, Frydman R. Uterine contractions at the time of embryo transfer alter pregnancy rates after invitro fertilization. Hum Reprod 1998;13:1968–74. Zhu L, Xiao L, Che HS, Li YP, Liao JT. Uterine peristalsis exerts control over fluid migration after mock embryo transfer. Hum Reprod 2014;29:279–85. Practice Committee of the American Society for Reproductive Medicine. Endometriosis and infertility. Fertil Steril 2006;86:S156–60. de Ziegler D, Borghese B, Chapron C. Endometriosis and infertility: pathophysiology and management. Lancet 2010;376:730–8. Gryparis I, Nardo LG. Update in endometriosis and IVF. Minerva Ginecol 2011;63:571–6. Lefebvre DL, Farookhi R, Larcher A, Neculcea J, Zingg HH. Uterine oxytocin gene expression. I. Induction during pseudopregnancy and the estrous cycle. Endocrinology 1994;134:2556–61. Lefebvre DL, Farookhi R, Giaid A, Neculcea J, Zingg HH. Uterine oxytocin gene expression. II. Induction by exogenous steroid administration. Endocrinology 1994;134:2562–6. Leyendecker G, Kunz G, Noe M, Herbertz M, Mall G. Endometriosis: a dysfunction and disease of the archimetra. Hum Reprod Update 1998;4: 752–62. Mizumoto Y, Furuya K, Makimura N, Mitsui C, Seki K, Kimura T, et al. Gene expression of oxytocin receptor in human ectopic endometrial tissues. Adv Exp Med Biol 1995;395:491–3. Asselin E, Goff AK, Bergeron H, Fortier MA. Influence of sex steroids on the production of prostaglandins F2 alpha and E2 and response to oxytocin in
VOL. - NO. - / - 2016
28.
29. 30.
31.
32.
33.
34. 35.
36.
37. 38.
39.
40.
41.
cultured epithelial and stromal cells of the bovine endometrium. Biol Reprod 1996;54:371–9. Danet-Desnoyers G, Wetzels C, Thatcher WW. Natural and recombinant bovine interferon tau regulate basal and oxytocin-induced secretion of prostaglandins F2 alpha and E2 by epithelial cells and stromal cells in the endometrium. Reprod Fertil Dev 1994;6:193–202. Sales KJ, Jabbour HN. Cyclooxygenase enzymes and prostaglandins in pathology of the endometrium. Reproduction 2003;126:559–67. Rickes D, Nickel I, Kropf S, Kleinstein J. Increased pregnancy rates after ultralong postoperative therapy with gonadotropin-releasing hormone analogs in patients with endometriosis. Fertil Steril 2002;78:757–62. Husslein P, Quartarolo JP. Review of clinical experience with atosiban and the Tractocile Efficacy Assessment Survey in Europe (TREASURE) study protocol. Int J Clin Pract 2003;57:121–7. Vedernikov Y, Betancourt A, Shi SQ, Shi LL, Reinheimer T, Garfield RE. Oxytocin antagonistic effect of barusiban and atosiban in isolated uterine artery from late pregnant rats. J Soc Gynecol Invest 2006;13:192a. Fanchin R, Ayoubi JM, Olivennes F, Righini C, de Ziegler D, Frydman R. Hormonal influence on the uterine contractility during ovarian stimulation. Hum Reprod 2000;15(Suppl 1):90–100. Zhu L, Li Y, Xu A. Influence of controlled ovarian hyperstimulation on uterine peristalsis in infertile women. Hum Reprod 2012;27:2684–9. Purcell K, Schembri M, Frazier LM, Rall MJ, Shen S, Croughan M, et al. Asian ethnicity is associated with reduced pregnancy outcomes after assisted reproductive technology. Fertil Steril 2007;87:297–302. Huddleston HG, Rosen MP, Gibson M, Cedars MI, Fujimoto VY. Ethnic variation in estradiol metabolism in reproductive age Asian and white women treated with transdermal estradiol. Fertil Steril 2011;96:797–9. Noble LS, Simpson ER, Johns A, Bulun SE. Aromatase expression in endometriosis. J Clin Endocrinol Metab 1996;81:174–9. Noble LS, Takayama K, Zeitoun KM, Putman JM, Johns DA, Hinshelwood MM, et al. Prostaglandin E2 stimulates aromatase expression in endometriosis-derived stromal cells. J Clin Endocrinol Metab 1997;82: 600–6. Zingg HH, Rozen F, Chu K, Larcher A, Arslan A, Richard S, et al. Oxytocin and oxytocin receptor gene expression in the uterus. Recent Prog Horm Res 1995;50:255–73. Zhu L, Che HS, Xiao L, Li YP. Uterine peristalsis before embryo transfer affects the chance of clinical pregnancy in fresh and frozen-thawed embryo transfer cycles. Hum Reprod 2014;29:1238–43. Lan VT, Khang VN, Nhu GH, Tuong HM. Atosiban improves implantation and pregnancy rates in patients with repeated implantation failure. Reprod Biomed Online 2012;25:254–60.
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