Placental Pathology in Covid-19 Positive Mothers: Preliminary Findings

Abstract

This study describes the pathology and clinical information on 20 placentas whose mother tested positive for the novel Coronovirus (2019-nCoV) cases. Ten of the 20 cases showed some evidence of fetal vascular malperfusion or fetal vascular thrombosis. The significance of these findings is unclear and needs further study.

Keywords: Covid-19; pathology; placenta; pregnancy; thrombosis; villitis.

Figure 1.

Section of a stem vessel in the placenta showing fetal vascular malperfusion, specifically intramural fibrin deposition where fibrin is deposited in the intima of the vessel. This was the most common type of thrombotic lesion in these placentas. H&E original magnification 200×.

Figure 2.

Section of a chorionic plate vessel showing fetal vascular malperfusion, also with deposition of fibrin in the intimal of the vessel extending into the lumen. H&E original magnification 100×.

Figure 3.

Section of chorionic villi which are avascular. This is another lesion of fetal vascular malperfusion which develops due to thrombosis upstream from the chorionic villi leaving to loss of fetal circulation downstream from the thrombosis. Loss of circulation ultimately leads to loss of fetal vessels with preservation of surface trophoblast. Here, the villi are avascular and the stroma is hyalinized. H&E original magnification 400×.