Maryam Azizi, Minoo Rejaei, Zohreh Pezeshkpour, Mohammad Reza Alipour, Elham Kazemi, Shahram Zare, Seyedhossein Hekmatimoghaddam, Mohammadtaghi Sarebanhassanabadi
"Preterm labor is caused by several factors including placental infection and thrombosis. To define the changes in placenta of women with preterm labor, pathological examination of placenta is needed. This case control study aims to find correlation between pathological findings of preterm placentas and chance of preterm labor.Placentas of 100 preterm (either early or late) labors and 100 term deliveries were examined both macroscopically and microscopically. Any evidence of inflammatory lesion, calcification, hematoma and neoplastic mass was evaluated and compared. Early preterm deliveries frequently showed placental calcification, significantly more than in term deliveries (p=0.0001). Inflammatory lesions were present in 20% of placentas of full term newborns, in 60% of early preterm labors, and in 46% of late preterm newborns. Placental calcification and placental inflammatory lesions both may be considered as having a positive correlation with preterm labor (p=0.000).several changes are seen in placentas of women with preterm labor, reflecting potential etiologic roles. Each placenta in preterm labor should be pathologically examined for the presence of inflammatory lesions, abnormality of vessels, calcifications, hematomas, tumoral masses, etc. Ultrasound examination of placenta during pregnancy may reveal some of these lesions."