Elevated midtrimester α-fetoprotein and delivery markers of inflammation in a preterm population

Determine whether elevated second trimester maternal serum α-fetoprotein (AFP) is associated with clinical and histopathologic markers of inflammation at preterm delivery.

105 women <32 weeks' gestation were included. AFP levels were dichotomized at 2.0 multiples of the median (MoM). Rates of neonatal morbidities, clinical chorioamnionitis, cord blood IL-6 level, and placental inflammatory findings were compared.

Thirteen (12.4%) had elevated AFP. Fewer women with AFP ≥ 2 MoM had histologic placental or membrane rupture site inflammation, funisitis, or placental culture positive for Mycoplasma and Ureaplasma species, compared to those with normal AFP. Neonatal death was increased in the elevated AFP group (23.1% vs. 2.27%, RR 10.6). Elevated AFP was associated with a nonsignificant increase in indicated birth (54% vs. 35%; p = 0.225). Virtually all inflammatory findings were confined to the spontaneous delivery group.

Elevated midtrimester AFP conveyed significant risk of neonatal death, but was negatively associated with clinical or histopathologic inflammation in preterm infants.