Transmission between mom and preborn baby has not been shown to date. One recent study with a small sample size documented pregnant woman diagnosed with COVID-19 found no evidence for vertical transmission in late pregnancy.
 Clinical characteristics and intrauterine vertical transmission potential of COVID-19 infection in nine pregnant women: a retrospective review of medical records. Huijun Chen, PhD, Juanjuan Guo, MS, Chen Wang, PhD, Fan Luo, PhD, Xuechen Yu, MD, Prof Wei Zhang, PhD. VOLUME 395, ISSUE 10226, P809-815, Published: February 12, 2020D