A study to determine if certain sonographic uterine parameters are associated with multiple gestation

The objective was to determine if lower uterine artery vascular impedance is associated with a greater likelihood of multiple gestation. Color Doppler parameters of pulsatility index, resistance index, endometrial thickness and echo patterns were measured in oocyte/retrieval cycles on days of human chorionic gonadotropin injection, oocyte retrieval, and mid-luteal phase in cycles where at least 3 embryos were transferred. Comparisons of these parameters were made in patients with single versus multiple gestations. There was no association between uterine environment as measured by vascular impedance and endometrial thickness and number of embryos implanted. Thus, a more ideal uterine environment, at least as determined by these sonographic parameters, does not seem to facilitate multiple embryo implantations.