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Updated: Aug 30, 2026

The Immediate Partial Removal of Cumulus-Oocyte Complexes: A Refined Approach for Rapid Observation of In Vitro Fertilization
Published on: October 18, 2024
Cervical dilatation with hygroscopic rods prior to ovarian stimulation facilitates embryo transfer
Paul Serhal1, Domenico Massimo Ranieri, Iffat Khadum
1The Assisted Conception Unit, University College London Hospitals, 25 Grafton Way, London WC1E 6DB, UK. paul.serhal@uclh.org
Background:
Embryo transfer is a critical factor affecting the success of IVF-the ease of embryo transfer has a direct impact on the success rate. The aim of this study was to assess the value of cervical dilatation with hygroscopic cervical rods (Dilapan-S) in patients with difficult embryo transfer.
Methods:
Fifty-four patients undergoing IVF treatment, who either failed to conceive after previous difficult embryo transfer or were noted to have difficult mock embryo transfer were retrospectively included in the study. In this way the patients acted as control for themselves. The Dilapan-S rods were placed intracervically and left for 4 h prior to starting gonadotrophin stimulation as an outpatient procedure.
Results:
Of the 54 patients who originally had difficult embryo transfer, 43 patients (79.5%) had subsequent easy embryo transfer. Thirty patients managed to conceive, giving a clinical pregnancy rate of 55%.
Conclusions:
Cervical dilatation using hygroscopic dilators facilitates difficult embryo transfer and helps to improve the pregnancy rate.

