Vascularization in first-trimester chorionic villi in complicated and uncomplicated pregnancies.

OBJECTIVE

The purpose of this study was to investigate possible altered chorionic vascularization patterns that are seen already in the first trimester of pregnancies that are complicated by hypertensive disorders or intrauterine growth restriction (IUGR) in the third trimester of pregnancy.

STUDY

DESIGN

After chorionic villous sampling, surplus of villi were stored, and a selection was made of pregnancies that were complicated further by hypertensive disorders (n = 26), normotensive IUGR (n = 13), and matched control subjects (n = 60). Vascular parameters of these villi were analyzed with a video-image-analysis system.

RESULTS

In pregnancies that are complicated by early-onset hypertensive disorders and IUGR, the mean distance of the peripheral vessels to the intervillous space and the total of the distances (central and peripheral) are significantly smaller, compared with control subjects (9.3% and 13.8% for hypertensive disorders and 12.2% and 16.1% for IUGR, respectively).

CONCLUSION

Differences in vascularization patterns in the placenta already in the first trimester of pregnancies that are complicated later by hypertensive disorders or IUGR confirm the hypothesis of early changes by means of more vessels and more peripheral vessels that are located in chorionic villi.