Fibroids that do not distort the uterine cavity and IVF success rates: an observational study using extensive matching criteria.

OBJECTIVE: To assess the impact of non-cavity-distorting fibroids on in vitro fertilisation (IVF) pregnancy outcomes. DESIGN: A retrospective, matched, single-centre, cohort study was performed. SETTING: The IVF unit of a tertiary, university hospital. POPULATION: We analysed all women with non-cavity-distorting uterine fibroids undergoing IVF/intracytoplasmic sperm injection (ICSI) cycles from 1 January 2011 to 1 May 2015. METHODS: Each woman was matched with two separate controls of the same age (±6 months), stimulation protocol (gonadotropin-releasing hormone agonist or antagonist), starting dose of follicle-stimulating hormone (FSH), number of embryos transferred (one or two), day of transfer (day 3 or day 5), and no uterine fibroids identified by transvaginal ultrasound. MAIN OUTCOME MEASURES: Clinical pregnancy and live birth rates. RESULTS: Our study demonstrates that the presence of non-cavity-distorting fibroids appears to negatively affect clinical pregnancy (odds ratio, OR 0.62; 95% confidence interval, 95% CI 0.41-0.94) and live birth rates (OR 0.58; 95% CI 0.48-0.78) in patients undergoing their first IVF/ICSI cycle, when matched with controls of the same age, starting dose of FSH, stimulation protocol, number of embryos, and day of embryo transfer. The deleterious effect of fibroids on live birth rates was significant in women with two or more fibroids (OR 0.47; 95% CI 0.26-0.83) and in women with fibroids of ≥30 mm in diameter (OR 0.41; 95% CI 0.19-0.89). The negative impact of non-cavity-distorting fibroids was also present in women with an embryo transfer on day 5 (OR 0.58; 95% CI 0.35-0.94). Conversely, in women with single fibroids of <30 mm in diameter, no difference in pregnancy outcomes was identified. CONCLUSIONS: A well-designed, adequately powered, randomised controlled trial is required to address the role of medical or surgical interventions in patients with intramural and subserosal fibroids before undergoing fertility treatment. TWEETABLE ABSTRACT: Non-cavity-distorting fibroids negatively affect pregnancy rates after IVF.

Pharmacogenetics in ovarian stimulation--current concepts.

Ovarian response to follicle-stimulating hormone (FSH) action differs considerably among women; this has prompted researchers to determine which factors modify this response. The challenge is to identify the genes that affect the response to FSH stimulation by the application of pharmacogenetics to assisted reproduction techniques (ARTs). Recently, new insights have been gained in the investigation of the variability in the gene that encodes the FSH receptor (FSHR) gene or genes of the estrogen pathway. Several polymorphisms of the FSHR gene have been discovered, but Ser680Asn and Thr307Ala are the two most studied. The Ser680Asn polymorphism of the FSHR gene has been found to influence the ovarian response to FSH stimulation in women undergoing in vitro fertilization (IVF), and in women with the genotype Ser/Ser, the FSHR appears to be more resistant to FSH action. The clinical implications of this finding are highly important; the ultimate goal is to apply genetic markers as routine diagnostic tests before ovarian stimulation to predict ovarian response, determine the required FSH dose, and avoid the possible complications related to FSH stimulation.

Corifollitropin alfa: a novel long-acting recombinant follicle-stimulating hormone agonist for controlled ovarian stimulation.

The advent of recombinant technology has made the production of modified proteins with desired properties possible. Corifollitropin alfa is a successful example of the first available long-acting, follicle stimulating hormone. Corifollitropin alfa has prolonged half-life and a slower absorption rate, but has the same receptor-binding and biological activity as recombinant FSH (rFSH). Its application is associated with the arrival of a novel simplified approach for controlled ovarian stimulation in IVF patients. Different studies have proven the efficiency of a single corifollitropin alfa dose to initiate and sustain multiple follicular development in a gonadotropin-releasing hormone antagonist protocol. Finally, corifollitropin alfa is well tolerated and is not correlated with serious adverse events, except for the slightly higher incidence of ovarian hyperstimulation syndrome compared with traditional management with recombinant FSH.