Effect of first-trimester serum from pregnant women with high-resistance uterine artery Doppler resistance on extravillous trophoblast invasion.

BACKGROUND Abnormal uterine artery Doppler indices are associated with pregnancy complications such as pre-eclampsia and intrauterine growth restriction. Poor trophoblast invasion may be a consequence of, or be associated with, abnormal Doppler indices. OBJECTIVE To evaluate in vitro trophoblast function following exposure to first-trimester serum from pregnancies with high uterine artery Doppler resistance indices. METHODS Doppler ultrasound examination of the maternal uterine arteries was performed on women at 10-14 weeks' gestation. Serum was collected from women with bilateral uterine artery notches with resistance indices above the 95th centile and from patients with normal uterine artery indices. The effect of serum on trophoblast invasion was determined using an established in vitro model from the extravillous trophoblast-derived cell line SGHPL-4. RESULTS Trophoblastic invasion was significantly reduced when treated with serum from women with high-resistance compared with normal-resistance uterine artery Doppler indices (P < 0.05). CONCLUSION Maternal serum in the first trimester of pregnancy from patients with high-resistance uterine artery Doppler indices appears to inhibit trophoblast invasion. This experimental model allows further investigation of factors responsible and the evaluation of therapeutic strategies.