Placenta
Gestational trophoblastic disease
Abnormal (nonmolar) villous lesions
Fetal trisomies
Author: Mandolin S. Ziadie, M.D.
Last author update: 1 November 2011
Last staff update: 19 April 2021
Copyright: 2002-2024, PathologyOutlines.com, Inc.
PubMed Search: Fetal trisomies placenta[title]
Cite this page: Ziadie MS. Fetal trisomies. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/placentatrisomy.html. Accessed April 19th, 2024.
Trisomy 13
- Often abnormal placenta (small placental volume, reduced placental vascularization, a partial molar appearance, placental mesenchymal dysplasia) and preeclampsia (Taiwan J Obstet Gynecol 2009;48:3)
- Also retinal dysplasia: retinal pigment epithelium within optic nerve or unilateral malformed eye not associated with other anomalies (such as persistent hyperplastic primary vitreous); histology shows series of straight branching tubes composed of abortive rod and cone layers (Arch Pathol Lab Med 1977;101:540)
Laboratory
- Trisomy 21: elevated serum hcG and inhibin, reduced serum estradiol and AFP
- Trisomy 18: low serum hcG, low AFP, low inhibin and low estradiol
Gross description
- Single umbilical artery is more common in trisomic pregnancies
- Early spontaneous abortions may show no fetal parts and an absent umbilical cord (Hum Pathol 1995;26:201)
Microscopic (histologic) description
- Large hypovascular / avascular villi with irregular borders accompanied by normal appearing villi
- Villous hydrops is also seen though less than in other abnormal karyotypes
