Divergent trophoblast invasion and apoptosis in placental bed spiral arteries from pregnancies complicated by maternal anemia and early-onset preeclampsia/intrauterine growth restriction

Objective: Impaired trophoblast invasion into spiral arteries is associated with early-onset intrauterine growth restriction and preeclampsia. We compared trophoblast invasion into spiral arteries in pregnancies with maternal anemia or early-onset preeclampsia/intrauterine growth restriction and related these findings to trophoblast apoptosis. Study design: Full-thickness uterine wall samples were obtained from women with early-onset preeclampsia/intrauterine growth restriction (n = 6), normal pregnancies (n = 5), and chronic anemia (n = 8). Trophoblast invasion into the walls of spiral arteries was quantified by morphometric analysis of paraffin sections stained with anticytokeratin 18, antiactin, and anticytokeratin 18 neoepitope (M30) antibodies. Results: Trophoblast invasion into spiral arteries was increased in anemic pregnancies (mean [SD]: 206 [46] cell profiles/mm(2)) and severely impaired in preeclamptic/intrauterine growth restriction pregnancies (17 [6]), compared with normal subjects (149 [52]). Spiral artery lumen area was increased in anemia (0.07 [0.03] mm(2)) versus normal pregnancies (0.09 [0.04] mm(2)) and reduced in preeclampsia/intrauterine growth restriction (0.04 [0.02] mm(2)). Trophoblast apoptosis was similar in anemic (4.2% [3.4%]) and normal (5.0% [1.9%]) pregnancies but increased in preeclampsia/intrauterine growth restriction (12% [5.6%]). Conclusion: Trophoblast invasion into the placental bed in early-onset preeclampsia/intrauterine growth restriction is limited by increased apoptosis, resulting in narrower spiral arteries, which is in contrast to findings in anemia. (c) 2006 Mosby, Inc. All rights reserved.