Prediction of Ovarian Hyperstimulation Syndrome in Patients Treated with Corifollitropin alfa or rFSH in a GnRH Antagonist Protocol.

STUDY QUESTION: What is the threshold for the prediction of moderate to severe or severe ovarian hyperstimulation syndrome (OHSS) based on the number of growing follicles ≥ 11 mm and/or estradiol (E2) levels? SUMMARY ANSWER: The optimal threshold of follicles ≥11 mm on the day of hCG to identify those at risk was 19 for both moderate to severe OHSS and for severe OHSS. Estradiol (E2) levels were less prognostic of OHSS than the number of follicles ≥ 11 mm. WHAT IS KNOWN ALREADY: In comparison to long gonadotropin-releasing hormone (GnRH) agonist protocols, the risk of severe OHSS is reduced by approximately 50% in a GnRH antagonist protocol for ovarian stimulation prior to in vitro fertilisation (IVF), while the two protocols provide equal chances of pregnancy per initiated cycle. Nevertheless, moderate to severe OHSS may still occur in GnRH antagonist protocols if human chorionic gonadotropin (hCG) is administered to trigger final oocyte maturation, especially in high responder patients. Severe OHSS following hCG trigger may occur with an incidence of 1-2% in a relatively young (aged 18 to 36 years) IVF population treated in a GnRH-antagonist protocol. STUDY DESIGN, SIZE, DURATION: From the Engage, Ensure and Trust trials, in total, 2,433 women who received hCG for oocyte maturation and for whom the number of follicles ≥ 11 mm and the level of E2 on the day of hCG administration were known were included in the analyses. PARTICIPANTS/MATERIALS, SETTING, METHODS: The threshold for OHSS prediction of moderate and severe OHSS was assessed in women treated with corifollitropin alfa or daily recombinant follicle stimulation hormone (rFSH) in a gonadotropin-releasing hormone (GnRH)-antagonist protocol. Receiver operating characteristics curve analyses for moderate to severe OHSS and severe OHSS were performed on the combined dataset and the sensitivity and specificity for the optimal threshold of number of follicles ≥ 11 mm, E2 levels on the day of (hCG), and a combination of both, were determined. MAIN RESULTS AND THE ROLE OF CHANCE: The optimal threshold of follicles ≥ 11 mm on the day of hCG to identify those at risk of moderate to severe OHSS was 19 (sensitivity and specificity 62.3% and 75.6%, respectively) and for severe OHSS was also 19 (sensitivity and specificity 74.3% and 75.3%, respectively). The positive and negative predictive values were 6.9% and 98.6%, respectively, for moderate to severe OHSS, and 4.2% and 99.5% for severe OHSS. LIMITATIONS, REASONS FOR CAUTION: This was a retrospective analysis of combined data from three trials following ovarian stimulation with two different gonadotropins. WIDER IMPLICATIONS OF THE FINDINGS: For patients with 19 follicles or more ≥11 mm on the day of hCG, measures to prevent the development of OHSS should be considered. Secondary preventive measures include cycle cancellation or coasting, use of a GnRH agonist to trigger final oocyte maturation in place of hCG and a freeze all strategy. TRIAL REGISTRATION: ClinicalTrials.gov NCT00702845 NCT00696800 NCT00696878.

Prognostic models for high and low ovarian responses in controlled ovarian stimulation using a GnRH antagonist protocol.

STUDY QUESTION: Can predictors of low and high ovarian responses be identified in patients undergoing controlled ovarian stimulation (COS) in a GnRH antagonist protocol? SUMMARY ANSWER: Common prognostic factors for high and low ovarian responses were female age, antral follicle count (AFC) and basal serum FSH and LH. WHAT IS KNOWN ALREADY: Predictors of ovarian response have been identified in GnRH agonist protocols. With the introduction of GnRH antagonists to prevent premature LH rises during COS, and the gradual shift in use of long GnRH agonist to short GnRH antagonist protocols, there is a need for data on the predictability of ovarian response in GnRH antagonist cycles. STUDY DESIGN, SIZE, DURATION: A retrospective analysis of data from the Engage trial and validation with the Xpect trial. Prognostic models were constructed for high (>18 oocytes retrieved) and low (<6 oocytes retrieved) ovarian response. Model building was based on the recombinant FSH (rFSH) arm (n = 747) of the Engage trial. Multivariable logistic regression models were constructed in a stepwise fashion (P < 0.15 for entry). Validation based on calibration was performed in patients with equivalent treatment (n = 199) in the Xpect trial. PARTICIPANTS/MATERIALS, SETTING, METHODS: Infertile women with an indication for COS prior to IVF. The Engage and Xpect trials included patients of similar ethnic origins from North America and Europe who had regular menstrual cycles. The main causes of infertility were male factor, tubal factor and endometriosis. MAIN RESULTS AND THE ROLE OF CHANCE: In the Engage trial, 18.3% of patients had a high and 12.7% had a low ovarian response. Age, AFC, serum FSH and serum LH at stimulation Day 1 were prognostic for both high and low ovarian responses. Higher AFC and LH were associated with an increased chance of high ovarian response. Older age and higher FSH correlated with an increased chance of low ovarian response. Region (North America/Europe) and BMI were prognostic for high ovarian response, and serum estradiol at stimulation Day 1 was associated with low ovarian response. The area under the receiver operating characteristic (ROC) curve (AUC) for the model for a high ovarian response was 0.82. Sensitivity and specificity were 0.82 and 0.73; positive and negative predictive values were 0.40 and 0.95, respectively. The AUC for the model for a low ovarian response was 0.80. Sensitivity and specificity were 0.77 and 0.73, respectively; positive and negative predictive values were 0.29 and 0.96, respectively. In Xpect, 19.1% of patients were high ovarian responders and 16.1% were low ovarian responders. The slope of the calibration line was 0.81 and 1.35 for high and low ovarian responses, respectively, both not statistically different from 1.0. In summary, common prognostic factors for high and low ovarian responses were female age, AFC and basal serum FSH and LH. Simple multivariable models are presented that are able to predict both a too low or too high ovarian response in patients treated with a GnRH antagonist protocol and daily rFSH. LIMITATIONS, REASONS FOR CAUTION: Anti-Müllerian hormone was not included in the prediction modelling. WIDER IMPLICATIONS OF THE FINDINGS: The findings will help with the identification of patients at risk of a too high or too low ovarian response and individualization of COS treatment. STUDY FUNDING/COMPETING INTERESTS: Financial support for this study and the editorial work was provided by Merck, Sharp & Dohme Corp. (MSD), a subsidiary of Merck & Co. Inc., Whitehouse Station, NJ, USA. F.J.B. received a grant from CVZ to his institution; P.J.M.V. and H.W. are employees of MSD, and B.M.J.L.M. was an employee of MSD at the time of development of this manuscript. TRIAL REGISTRATION NUMBERS: NCT 00696800 and NCT00778999.

A novel guinea pig model of Chlamydia trachomatis genital tract infection.

Genital Chlamydia trachomatis infections often result in pelvic inflammatory disease and sequelae including infertility and ectopic pregnancies. In addition to the already established murine models, the development of other animal models is necessary to study the safety and efficacy of prototype vaccine candidates. The intravaginal infection of guinea pigs with C. trachomatis has been tested in three independent studies. The first two studies investigated the effect of hormonal treatment of the animals prior to infection with serovars D and E. The results showed that estradiol treatment was required for sustained infection. The third study conducted an immunization-challenge experiment to explore the feasibility of measuring protection in this guinea pig model. C. trachomatis bacteria were sampled using vaginal swabs and measured by qPCR. Using immunohistochemistry the bacteria were detected in the oviducts 19 days post-infection, indicating that the estradiol treatment resulted in ascending infection. Furthermore, immunization of guinea pigs with live EB formulated with ISCOM matrix led to reduction of cervico-vaginal shedding and diminished the severity of pathology. In this study we have developed a new guinea pig model of C. trachomatis female genital tract infection for the purpose of evaluating potential vaccine candidates.

Endometrial effects of tibolone in elderly, osteoporotic women.

OBJECTIVE: To investigate endometrial effects of tibolone administered to postmenopausal women for 3 years. METHODS: Postmenopausal women (N=3,519) aged 60-85 years (mean 68 years) with a uterus and with osteoporosis were randomly assigned to receive tibolone orally, 1.25 mg per day, or identical placebo. We evaluated effects on endometrial thickness in all women, and examined endometrial histology in 635 participants considered to be at increased risk for abnormalities (with unexpected vaginal bleeding or endometrial thickness more than 4 mm). RESULTS: During the first year of study, mean endometrial thickness increased 1 mm in women receiving tibolone (P<.001), but no further increases were noted during the next 2 years. Diagnostic biopsies among 499 women receiving tibolone and 136 who were receiving placebo showed cumulative incidences of endometrial hyperplasia less than 1%. Among the 15% of women whose biopsy showed an endometrial polyp (similar rate in tibolone and placebo), those receiving tibolone were more than twice as likely to show hyperplasia within the polyp. A marginal increase in grade 1 endometrioid adenocarcinoma (P=.06 compared with placebo) was found among women receiving tibolone. Prevalences of vaginal bleeding during the study were 10.8% in the tibolone group and 2.8% in the placebo group (P<.001). CONCLUSION: Tibolone treatment during 3 years minimally increased endometrial thickness, hyperplastic polyps, endometrial carcinoma, and vaginal bleeding.