One hundred and thirteen (66.5%) women in this study had a normal intrauterine pregnancy with ages ranging 6 to 12 weeks of gestation. Fifty-seven (33.5%) patients were admitted to the hospital owing to clinically suspected abnormal early pregnancy. Dilatation and curettage were done on all women and tissue sample sent to the pathologist for a final diagnosis. Diagnosis of ectopic pregnancy was made on laparoscopy. Both ovaries were examined carefully by color Doppler in sonography in all patients. Color flow was used as a guide for pulsed Doppler exploration. Corpus luteum blood flow was defined as random, usually semilunar in appearance, dispersed vessels with very low impedance to blood flow. The resistive index and pulsatility index were calculated. Overall detection rate of corpus luteum blood flow in normal pregnancies was higher for the left ovary (62.6%) than for the right ovary (37.4%) (P ≤ 0.01). The mean resistive and pulsatility indices from corpus luteum blood flow were not influenced by gestational age in normal pregnancy. The overall mean value for resistive index was 0.452 ± 0.04 and for pulsatility index 0.636 ± 0.09. The overall detection rate of corpus luteum in abnormal pregnancies also was higher for the left ovary (56.7%) than for the right ovary (43.4%) (P ≤ 0.01). The mean resistive indices from corpus luteum blood flow in patients with missed abortion was higher than in women with normal pregnancy (P ≤ 0.01). Both resistive and pulsatility indices were higher in patients with incomplete or threatened abortion in comparison with normal pregnancy (P ≤ 0.01). No statistically significant difference was seen in the case of anembryonic, molar, or ectopic pregnancy. The resistive and pulsatility indices are correlated in all groups of patients (r = 0.71). A precise role for color Doppler evaluation of corpus luteum vascularization has yet to be defined. It seems probable there is a significant role for this diagnostic imaging method in the study of luteal intraovarian angiogenesis. The relationship between corpus luteum blood flow and pregnancy prognosis can be of particular clinical interest.