Contributed by Lananh Nguyen, MD and W. Tony Parks, MD
The mother of this fetus was a 24 year old G1 P0 woman with multiple medical problems. These include cerebral palsy, mixed hearing loss, a history of seizures, history of a heart murmur, surgery for cleft lip, and asthma. The current pregnancy was without complications through the first two trimesters. An 18 week anatomy scan was unremarkable. A fetal echocardiogram at 18 weeks was also unremarkable. Early in the third trimester, a clinical concern for size less than dates arose. An ultrasound at 30 weeks found an enlarged fetal heart. No evidence of hydrops was identified, however. On a routine clinic visit at 32 2/7 weeks gestation, the mother complained of no fetal movement for the previous two days. A bedside ultrasound confirmed an intrauterine fetal demise. Labor was induced, with delivery of the stillborn female fetus.
GROSS PATHOLOGIC FINDINGS
This was a stillborn fetus with a gestational age of 32 2/7 weeks clinically and no congenital anomalies or external dysmorphisms. The fetus showed moderate subcutaneous edema and bilateral orbital edema. There were bilateral pleural effusions, an enlarged heart with four chamber dilatation and a markedly dilated right atrium. Petechial hemorrhages were noted on the pericardium and bilateral pleural surfaces.
The placenta was large (>90 percentile). On cut section, there were multiple discrete tan-red nodules ranging from 0.5 cm to 2.5 cm in greatest dimension, overcrowding the surrounding tan-pink spongy parenchyma. These nodules occupied approximately 75% of the total placental volume and were predominately clustered subjacent to the fetal surface.
MICROSCOPIC PATHOLOGIC FINDINGS
The fetal organs contained increased numbers of nucleated erythrocytes. Congestion of the thoracic organs with small hemorrhages was also seen.
The placental nodules were comprised of villous structures covered with a layer of trophoblast and containing large numbers of small vessels. The vessels were typically blood-filled, some distended by the blood. Occasional larger, thicker-walled vessels were also seen. Nucleated erythrocytes were easily located within the vessels. The maturation of the placenta not involved by the nodular lesions was consistent with the gestational age of 32 weeks.