Invasive diagnostic procedures and risk of hypertensive disorders in pregnancy.

Objective: To determine whether the risk of hypertensive complications differs among low-risk women who undergo prenatal diagnosis via chorionic villus sampling (CVS) and amniocentesis.

Methods: In a retrospective study, data were analyzed from women who underwent prenatal diagnosis by CVS or amniocentesis at Alexandra Maternity Hospital, Athens, Greece, between 1998 and 2011. All women had either transabdominal CVS at 10-13 weeks of pregnancy with a 20-gauge needle, or amniocentesis at 17-21 weeks with a 22-gauge needle, both under direct ultrasound guidance. Only women who had cytogenetically normal pregnancies and delivered at the study hospital were included. The main outcome measure was the development of hypertensive complications.

Results: Overall, 3243 women who underwent CVS and 6875 woman who underwent amniocentesis met the inclusion criteria, and their outcomes were analyzed. In total, 237 women (2.3%) developed hypertensive disorders during their pregnancy. The incidence of pre-eclampsia (2.4% vs. 0.8%) and total hypertensive disorders (3.8% vs. 1.7%) was significantly higher (P<0.001) in the CVS group than in the amniocentesis group.

Conclusion: Women who underwent CVS had a significantly higher risk of developing hypertensive disorders in comparison to those who underwent amniocentesis. This finding warrants further investigation via a well-designed prospective randomized trial.