方法：1998年から2003年に当院に入院した極低出生体重児のうち，CLD78例を対象とした。分類に際して，我々はⅢ型・Ⅲ' 型の“出生前感染”を，胎盤に亜急性絨毛膜羊膜炎（subacute chorioamnionitis 以下SCAM）を認めるものとし，Ⅳ型には絨毛膜羊膜炎を含めなかった。
結果：対象の平均在胎週数は26.2±2.2週，出生体重は806±212gであった。SCAMは，Ⅲ型・Ⅲ' 型で100％,Ⅱ型で5％に見られたが，その他の型ではなかった。Ⅳ型は，経産，繰り返す性器出血，び漫性絨毛膜羊膜ヘモジデローシス（diffuse chorioamniotic hemosiderosis 以下DCH）の頻度が他の型より多かった（p＜0.05）。Ⅲ型とⅣ型はレ線所見および酸素依存性などの臨床像は似ているが，胎盤所見および出生時の検査所見は明らかに違った。
結論：DCHは，サーファクタント欠乏症，SCAMと同様，独立したCLDの素因のひとつであると考えられた。
Design：Using data from retrospective charts review, we analyzed 78 very low birth weight（VLBW）infants who admitted on day 0 to the neonatal intensive care unit of Kanagawa Children’s Medical Center during 1998-2003.
We considered subacute chorioamnionitis（SCAM）as“antenatal infection”and included an infant with SCAM in the typeⅢ, Ⅲ’ unless he developed surfactant deficiency. We excluded any chorioamnionitis from the type Ⅳ.
Results：Study infants’ mean and standard deviation of gestational age and birth weight at delivery were 26.2±2.2 weeks and 806±212 grams, respectively. Frequency of CLD in VLBW-infants was 21.1％. This number and the distribution of cases according to the types were similar to those of the national study. Frequencies of SCAM in the type Ⅰ, Ⅱ, Ⅲ, Ⅲ’, Ⅳ, Ⅴ were 0, 5, 100, 100, 0, and 0 ％, respectively. Frequencies of diffuse chorioamniotic hemosiderosis （DCH）were, 13, 2.6, 29, 0, 90, 0 ％, respectively. Mothers from the type Ⅳ were more likely to be multiparous and to develop recurrent episodes of genital bleeding than mothers from the other types. Placentas from the type Ⅳ were more likely to show DCH than placentas from the other types. Although chest X-ray findings and oxygen dependency were similar, placental findings and laboratory data at delivery were different between in infants from the type Ⅲ and Ⅳ.
Conclusion：DCH is an independent predisposing factor for CLD, as well as surfactant deficiency and SCAM.
