Gross and Histopathological Findings of 111 Triplet Placentas: A Descriptive Analysis

Abstract

Introduction:

Triplet pregnancies have risen in recent decades due to assisted reproductive technology (ART) and are considered high-risk. Placental evaluation is crucial to understanding their outcomes, yet pathological findings in triplet placentas remain poorly described.

Design:

Retrospective observational study including all triplet pregnancies followed at a tertiary referral hospital from January 2000 to December 2024, whose placentas were submitted for pathological analysis. Gross and microscopic findings were reviewed.

Results:

We analyzed 111 triplet pregnancies (333 fetuses). Fetal loss (miscarriage or stillbirth) occurred in 7.5%. ART accounted for 70.3% of conceptions. Median gestational age at delivery was 32 weeks (P25 = 30; P75 = 34), with 50.4% being trichorionic triamniotic. Mean placental weight was 869 ± 243 g, and median size was 22.5 cm (P25 = 18; P75 = 30). Abnormal umbilical cord insertion was found in 52.2% of cases. Central or peripheral infarcts were present in 43.8% of placentas. The most common histological findings were accelerated villous maturation (65.1%), chorangiosis (53.7%), intervillous fibrin deposits (29.4%), and villous edema (24.3%). Chronic villitis of unknown etiology was the most frequent inflammatory lesion (9.3%).

Conclusions:

Triplet placentas exhibit high rates of pathological abnormalities, which may contribute to adverse outcomes. Future studies should explore associations with ART and chorionicity.