594 SARS-CoV-2 in pregnancy, placental fetal vascular malperfusion and the effect on fetal heart rate tracings

Objective: The effect of SARS-CoV-2(SV) on the pregnant population is unclear. SV has been associated with significant placental changes, most notably, fetal vascular malperfusion (FVM). The objective of this study is to evaluate placental effects through fetal heart tracings (FHT) among laboring SV+ patients. Study Design: A prospective study including all women delivering at a large urban hospital in Miami, Florida between April 30 - July 31, 2020 was performed. Admitted patients were screened for SV. The FHT in all SV positive cases and SV negative controls 2 hours prior to delivery were evaluated for the presence of late decelerations, severe variable decelerations, loss of variability and persistent tachycardia. Cases and controls were matched for age, race, BMI, gestational age and comorbidities. Two investigators blinded to perinatal outcomes independently evaluated FHTs, and a 3rd resolved discrepancies. Placentas were graded by a perinatal pathologist based on Amsterdam Placental Workshop Group criteria. Result(s): 224 subjects consented to participate. 188 (83.9%) were negative and 36 (16.0%) were positive for SV. Placentas from SV positive participants were more likely to show FVM (P=0.001). FHT for all SV positive patients who underwent labor (n= 26) were compared to 27 paired SV negative controls. Baseline demographic characteristics were not different between the two groups. (Table 1) There was no difference in the rates of absent variability, late decelerations, severe variable decelerations, persistent fetal tachycardia or a composite of any of these abnormal fetal heart rate patterns between the two study groups. (Table 2) Conclusion(s): Despite significant findings on placental pathology, no association was found between SV positivity and abnormal fetal heart tracings during labor. FHT was not a strong indicator of FVM in this cohort. Further studies are needed to fully understand the perinatal effects of the noted placental abnormalities in SV positive pregnant and laboring women. [Formula presented] [Formula presented]Copyright © 2020