RESUMO
BACKGROUND: To investigate flow in the ductus venosus at 11-13 + 6 weeks of gestation in women with normal pregnancies in the Taiwanese population. METHODS: Two hundred and fifty-two normal singleton pregnancies with gestational ages ranging from 11 to 13 + 6 weeks were examined in this study. The pulsatility index for veins (PIV), resistance index (RI), peak velocity during ventricular systole (S-wave), and peak velocity during ventricular diastole (D-wave) were recorded from the ductus venosus. RESULTS: We analyzed 252 participants who all fulfilled the inclusion and exclusion criteria of our study. The mean maternal age was 31 (range 19-45 years), with a corresponding gestational age of 12 + 4 weeks (range 11-13 + 6). No significant change was found in the vascular indices as gestational age increased for the S-wave (S-wave = 1.4214 (GA) + 17.448, r = 0.09, P = 0.154), PIV (PIV = -0.0358 (GA) + 1.4143, r = -0.05, P = 0.378) and RI (RI = -0.035 (GA) + 1.1478, r = -0.064, P = 0.468). In contrast, the D-wave behaved differently from the other variables. There was a significant increase (r = 0.155, P = 0.013) in the D-wave with gestational age (D-wave = 1.4896 (GA) - 7.1547). CONCLUSION: D-wave velocity in the ductus venosus increased with gestational age. S-wave peak velocity showed an increasing trend and PIV showed a decreasing trend with gestational age, but they did not reach statistical significance.
