Do placentae of term singleton pregnancies obtained by assisted reproductive technologies differ from those of spontaneously conceived pregnancies?

The study was conducted to investigate the association of placental morphol ogical and histopathological features with term, singleton pregnancies obta ined by assisted reproductive technologies (ART), The study group comprised 45 consecutive women with a singleton pregnancy, obtained by ART, who deli vered at term. For each subject in the study group, the consecutive, matche d-for-age-and-parity woman, with a term singleton, spontaneously conceived pregnancy served as the controls. The placentae of both groups were subject to a detailed morphological and histopathological investigation by one pat hologist, who was blinded to specimen origin. Pregnancy complications, feta l weight and perinatal outcome were similar in both groups, No differences in morphological or histopathological features of the placenta were observe d between the groups. Nevertheless, the placentae of the study group showed a borderline, significantly higher placental weight and placental:fetal we ight ratio, and placental thickness was significantly higher. Abnormal umbi lical cord insertion was significantly more prevalent in the study group. N either the specific ART method employed, nor the infertility factor affecte d the results, suggesting that multiple embryo transfers and/or ovulation i nduction protocols may account for these differences.