Midluteal-phase vaginal color Doppler assessment of uterine artery impedance in a subfertile population.

OBJECTIVE

To compare the midluteal uterine artery impedance to blood flow as measured by the pulsatility index in women with different causes of infertility with that of women with normal fertility and to correlate this with endometrial thickness.

DESIGN

A prospective study of normal women undergoing insemination with donor semen and subfertile women with tubal damage, endometriosis, premature ovarian failure, anovulation, or unexplained infertility.

SETTING

A tertiary infertility center.

PATIENTS: One-hundred sixty-one women (25 to 40 years of age) who were attending the clinic for subfertility treatment and 23 normal women who were having artificial insemination with donor sperm because their partners were azoospermic.

INTERVENTIONS: All women were examined by transvaginal ultrasonography, with color flow imaging and blood flow analysis, on day 21 of an unstimulated ovarian cycle.

MAIN OUTCOME MEASURES: The mean pulsatility index of the left and right uterine arteries and the endometrial thickness.

RESULTS

The patients were grouped according to the causes of infertility and compared with normal women. There were 23 women in the normal group (median pulsatility index, 1.91; range, 0.84 to 2.95), 35 with unexplained infertility (median pulsatility index, 2.45; range, 1.0 to 7.0), 91 with tubal damage (median pulsatility index, 2.65; range, 1.25 to 8.0), 8 with endometriosis (median pulsatility index, 2.32; range, 2.05 to 5.7), and 22 with anovulatory infertility (median pulsatility index, 3.03; range, 1.6 to 7.0). All the infertile groups had significantly different median pulsatility indexes when compared with the normal group, and the pulsatility indexes correlated with endometrial thickness.

CONCLUSIONS

The impedance to uterine artery blood flow is significantly different in women with different causes of infertility as compared with women of normal fertility. Increased resistance to uterine blood flow in the midluteal phase may be an important contributing factor to some causes of infertility and the cause of some previously "unexplained" infertility.