The objective of the study was to compare the placental maturity index (PMI) and pathohistological alterations of placentas from newborn/stillborns (NB) with or without congenital defects (CD). A case control study was carried out. N=25 CD cases and n=50 controls without CD were included. Cases were classified according to the presence of simple (n=17) or multiple (n=8) CD. Newborn/ stillborns with gestational age >20 weeks were included. Twin pregnancies were excluded. We collected information on clinical characteristics of the NB and the mother, NB anthropometry and APGAR score. The placenta was macro and microscopically examined to determine the presence and extension of histological alterations. The PMI was obtained by dividing the number of vasculo-syncytial membranes in 1 mm2, by their thickness (μ). The PMI (Mean ± SD) was 27.77 ± 14 in the control group, 30.31 ± 12 in the group diagnosed with simple CD, and 16.76 ± 1 in the group diagnosed with multiple CD (p<0.05. The rest of the assessed variables did not show significant difference between groups. In conclusion, this work shows a lower placental maturity associated with the presence of multiple CD.

KEY WORDS: Congenital defects; Placental maturity; Placenta; Histological alterations of placenta.