Unexpected effect of a nitric oxide donor on uterine artery Doppler velocimetry in oligomenorrheic women with polycystic ovaries

Abstract

We compared uterine artery vascular responses following administration of the nitric oxide donor glyceryl trinitrate to ten women with oligomenorrhea and ultrasound evidence of polycystic ovaries with those of nine women with a normal menstrual cycle and ultrasonically normal ovaries. Mean arterial blood pressure, pulse rate and uterine artery flow velocity waveforms were recorded before and 60-75 min after glyceryl trinitrate patch application. The pulsatility index and resistance index were calculated to describe changes in impedance to flow in the uterine artery. Peak systolic and time-averaged velocities were also measured. Pretreatment median arterial pressure was higher in women with polycystic ovaries (90 mmHg) compared to those with regular cycles (80 mmHg) (p < 0.05). No differences were found in pulse rate and uterine artery blood flow indices between the two groups. After glyceryl trinitrate patch administration, there was no change in blood pressure or pulse rate in either group. In women with polycystic ovaries, there was an increase in uterine artery resistance index (0.93 to 1.00; p < 0.05) and pulsatility index (3.77 to 4.99; p < 0.05) and a decrease in peak systolic (36.8 to 32.3 cm/s; p < 0.05) and time-averaged maximum (8.5 to 5.0 cm/s; p < 0.05) velocities. Uterine artery Doppler parameters remained unchanged in women with normal cycles. Uterine artery vascular responses to the nitric oxide donor glyceryl trinitrate are different in women with normal cycles compared to oligomenorrheic women with polycystic ovaries. This may be relevant to an understanding of the pathophysiology underlying the higher risk of cardiovascular morbidity and mortality associated with polycystic ovarian syndrome.