Assessment of uterine cavity size and shape: a systematic review addressing relevance to intrauterine procedures and events.

Uterine cavity measurement began with evaluation of post-mortem and surgical specimens. It has been extended in vivo by use of mechanical instruments and visualization techniques. This is a systematic review of the range of values for the uterine cavity and the practical implications of these measurements, Following a review of multiple data bases & a QUORUM analysis. Only articles with clearly defined quantitative measurements were included. Mechanical cavity measurements with a variety of instruments gave a mean endometrial cavity length (ECL) of 33.73 mm (18-22.1) and a mean endometrial cavity width (ECW) of 25.1 mm (17.8-32.2) for nulliparae. The values for multiparae were mean ECL 38.6mm(20.61-40.3) and mean ECW 34.9 mm (23.4-53). Imaging measurements for the uterine cavity by hysterography and ultrasound were mean ECL 44.3 mm (29-64) for multiparae and ECL 37 mm for nulliparae. Mean ECW was 28.2 mm (21-33) for nulliparae and 32.1 mm (26-38) for multiparae. There were wide variations due to parity, ethnicity and gestational states. Accurate measurement of intrauterine parameters is valuable for improving and enhancing many intrauterine procedures including IUD insertion, endometrial ablation, embryo placement in IVF and management of spontaneous and therapeutic abortion.