Predictive values of ultrasound monitoring of the menstrual cycle

This review summarizes the current knowledge about ultrasound scanning values in monitoring the structural and functional changes of the uterus and ovaries during the menstrual cycle.

The views that ovulation is more frequently right sided have been challenged, with recent data suggesting that ovulation occurs randomly. A 'follicular wave phenomenon', providing a new model for ovarian function during the menstrual cycle, has been described. Follicular development occurs in a wave-like fashion and women with two waves have earlier endometrial development due to earlier increase of the dominant follicle estrogen production. Myometrial contractions during menstrual cycle should be considered in the assessment of endometrial thickness. Uterine-ovarian arterial blood flow impedance is important in understanding the normal physiology of the menstrual cycle and may be of use in assisted conception protocols.

At present, ultrasound scanning has an important role in noninvasive assessment of endometrial and ovarian cyclical changes and may be of particular importance in assisted conception procedures. Further work is likely to help in understanding its full diagnostic potential.