Invasive procedures for fetal karyotyping: no cause of subsequent gestational hypertension or pre-eclampsia.

The aim was to estimate the risk of maternal hypertensive complications following first- or second-trimester invasive diagnostic procedures, i.e. chorionic villus sampling (CVS) and amniocentesis (AC). Odds ratios (ORs) for gestational hypertension, mild pre-eclampsia or severe pre-eclampsia were calculated for women who underwent CVS (n = 1,984) or AC (n = 21,748) compared with non-exposed women (n = 47,854). No increase in the development of gestational hypertension, mild pre-eclampsia or severe pre-eclampsia was observed. The results do not support an association between invasive procedures for fetal karyotyping and subsequent gestational hypertension or pre-eclampsia.