Corpus luteum blood flow in abnormal early pregnancy

Thirty-eight consecutive patients with the diagnosis of abnormal early singleton pregnancy were studied with transvaginal color velocity imaging and pulsed Doppler ultrasonography to assess corpus luteum blood flow. Mean gestational age was 8.5 weeks (range, 6 to 12 weeks). Patients' mean age was 30.9 years (range, 24 to 43 years). There were 19 (50%) threatened abortions, 13 (34.2%) missed abortions, and six (15.8%) anembryonic pregnancies. Blood flow impedance in the corpus luteum was estimated by calculating the resistive index. The results of this study group were compared with those obtained in a series of 85 normal singleton early pregnancies used as controls. Overall, detection of corpus luteum blood flow was 78.9% in study group and 76.4% in control group (P = 0.51). Mean resistive index +/- standard deviation in the control group was 0.50 +/- 0.10; the corresponding values in threatened abortion, anembryonic pregnancy, and missed abortion were 0.52 +/- 0.10, 0.42 +/- 0.06, and 0.57 +/- 0.05, respectively. No statistical differences in mean resistive index were found among threatened abortion and anembryonic pregnancy with respect to control group. A higher mean resistive index was observed in missed abortion than in control group (P < 0.01). Ln conclusion, our data show that luteal vascularization might be decreased in missed abortion but not in threatened abortion and anembryonic pregnancy.