Aim: To prospectively study the influence of the uterine junctional zone thickness measured on pelvic magnetic resonance imaging (MRI), on implantation rates during in vitro fertilization (IVF).
Methods: A prospective clinical-imaging study was conducted and included 152 female patients. Patients had a positive diagnosis of infertility and an indication for IVF. All patients had a pelvic MRI scan on a 1.5T magnet with T2-weighted sequences prior to IVF. The average junctional zone thickness value and the maximal junctional zone thickness values were measured. Implantation outcomes were correlated with junctional zone values and with infertility subtypes (endometriosis, tubal, dysovulation, male, unexplained).
Results: The mean number of embryo transfers per patient was 1.63, with a total pregnancy rate of 54%. Junctional zone thickness increase was significantly correlated with implantation failure at IVF: implantation failure rate was 95.8% for patients with an average junctional zone superior to 7 mm and a maximal junctional zone superior to 10 mm, versus 37.5% in other patient groups (P < 0.0001), independently from the cause of infertility or patients' age.
Conclusion: In a group of infertile patients engaged in an IVF program, a pelvic MRI scan showing a thickened uterine junctional zone is a negative predictive factor for embryo implantation after IVF.