PLATELET-ACTIVATING FACTOR-ACETYLHYDROLASE ACTIVITY FOLLOWING CHORIONIC VILLUS SAMPLING AND AMNIOCENTESIS

OBJECTIVE: Platelet activating factor (PAF) is essential for embryonic development and is a potent vasodilator. It increases vascular permeability and stimulates prostaglandin E(2) (PGE(2)) production. Platelet activating factor-acetylhydrolase (PAF-AH), the enzyme that degrades PAF, is synthesized by decidual macrophages. The aim of this study was to test the hypothesis that chorionic villus sampling (CVS) and/or amniocentesis might cause an increase in maternal PAF-AH activity. METHODS: Maternal plasma PAF-AH activity was evaluated before and after genetic amniocentesis (N = 13) and transcervical CVS (N = 29). A control group (N = 9) was evaluated to study the effects of venipuncture. RESULTS: Chorionic villus sampling caused a significant elevation in PAF-AH activity (P < .0005). No changes were noted in PAF-AH activity in the amniocentesis or the control group. CONCLUSIONS: Chorionic villus sampling causes subclinical release of PAF-AH, possibly from the decidual macrophages. Increased PAF-AH activity might result in decreased PAF levels, which might lead to vasoconstriction in the placental circulation due to lack of the vasodilator effects of PAF and possibly PGE(2). This mechanism might explain the increased risk for fetal limb reduction noted CVS performed at very early gestational ages.