Elevated maternal serum midtrimester alpha-feto protein is associated with feto-placental ischemia

OBJECTIVE: Elf\alioti of maternal serum alpha fetoproiein (MSAFP) in the second trimester is associated with poor pregnano outcome including leial demise, preterm deliver) and fetal growth restriction. We hvpothesi/ed that plaeental ischemia may he the common underlying pathogenesis of these outcomes. '1'hus we tested angiogenin. a potent indnce-r of neo\asculariJ.ation, in midtrhnester amniotic fluid of patients with elevated MSAFP to determine if AFP elevation is due to inadequate angiogenesis. STUDY DESIGN: In this case-control stuck, patients with elected MSAFP [>2.0 multiples of median (MoM). n=10] at triple screen uere mulched with l\\o controls (n-20) based on vear of amniocentesis, maternal age, race, and parity. Inclusion criteria were ( 1 ) singleton gestation, (2) no e\idence of fetal structural or chromosomal anomalies, and (3) underwent genetic amniocentesis. Amniotic fluid was immunoassaved for angiogenin (Quamikine. R&D Sv\tems; sensiti\it\ O.Oti ng/nil.. intei and intia-assa) coefticients of vaiiation 4.6, 2.9% respectively). Statistical aualvsis included one-wav AXOVA and regression with p<0.(l,r) significant. Augiogenin and MSAFP values \\ere normali/ed using natural log transformation ibi statistical anahsis. RESULTS: Angiogenin values uere significant!) elevated In patients with high MSAFP [median 30.2 (range 9.204.8) \s 17.2 (range 9.11-29.S) ng/ml., PO.02]. In addition, there ua.s a significant correlation between MSAFP MoM and angiogenin levels (r = 0.32. P = O.OS). Mean (iA at sampling, maternal age ant! \ear ol amniocentesis were not significant]) different between the stud) and control groups (each PXU))). CONCLUSIONS: AF angiogenin lev<'ls aie signiiicanth elevated in patients with ele\ated midtrimester MSAFP. Since angiogenin is a known market of l issue ischemia, resulting in neovasculari/ation. we hypothesi/e that election of MSAFP at triple screen is due to placenta! ischemia.