Table 1. Reports of potential vertical transmission.

Case	Country; city; hospital	Age (years)	Gestational age	Birth weight	Apgar score	Delivery	Main findings	Interval between onset of maternal disease and diagnosis in the neonate	Reasons why vertical transmission is not justified (or justified)
#1 Wang et al., 7 Hu et al., 8 Yu et al. 9	China; Wuhan; Tongji Hospital	34	39 weeks 6 days	3,250 g	8/9	Cesarean	Positive RT-PCR in th oropharynx swab – newborn 36 hours after delivery.	8 hours of maternal symptoms + 36 hours postpartum	Not justified: RT-PCR the in oropharynx swab collected after more than 12 hours of delivery.
#2 Dong et al. 10	China; Wuhan; Renmin Hospitalof Wuhan University	29	37weeks 6 days	3,120 g	9/10	Cesarean	Positive IgM and IgG 2 hours after delivery; negative RT-PCR in the oropharynx swab; IgM and IgG levels were reduced after 2 weeks; discharged.	25 days	Not justified: discordance among exams and negative RT-PCR in the oropharynx swab.
#3 Zamaniyan et al. 11	Iran; Sari; Imam Khomeini Hospital	22	32 weeks	2,350 g	8/9	Cesarean	Positive RT-PCR in the amniotic fluid collected during cesarean section (contamination?); negative RT-PCR in the oropharynx swab of the newborn; maternal death postpartum.	7 days	Not justified: positive RT-PCR in the amniotic fluid, but with the possibility of contamination with no other confirmation of the virus.
#4 Li et al. 5 and Ferrazzi et al. 12	China; Wuhan; Hubei Provincial Maternal and Child Health Center; 5 and Italy; Lombardy and Units of Padua and Modena 12	NR	NR	NR	NR	Vaginal	Positive RT-PCR in two newborns. In these two cases, because viral testing was not performed immediately after birth, postpartum transmission cannot be excluded.	Not informed	Not justified: the swab test was not performed shortly after birth.
#6 Alzamora et al. 13	Peru; Lima; British American Hospital	41	33 weeks	2,970 g	6/8	Cesarean	Positive RT-PCR in the nasopharyngeal swab – newborn 16 hours after delivery. Repeated in 48 hours: also positive.	5 days	Not justified: RT-PCR in the nasopharyngeal swab collected 12 hours after delivery.
#7 Vivanti et al. 14	France; Paris Saclay University Hospitals	23	35 weeks 5 days	2,540 g	4/1	Cesarean	Amniotic fluid collected during cesarean section positive on RT-PCR (Genes E and S). Nasopharyngeal and rectal swabs collected within 1 hour, 3 days and 18 days of life were positive on RT-PCR (Genes E and S). Blood and non-bronchoscopic bronchoalveolar lavage fluid collected before extubation (6 hours after delivery) positive on RT-PCR (Genes E and S).	5 days	Justified: positive RT-PCR in the amniotic fluid and in the neonate blood sample collected before 12 hours of delivery.
#8 Mehta et al. 15	United States; Liningston; Saint Barnabas Medical Center	39	27 weeks	Baby A: 925 g; Baby B: 1,050 g	Baby A: 1/3; Baby B: 5/6	Cesarean	Twin A tested positive and twin B tested negative for SARS-CoV-2 at 72 hours, and it is not clear what type of test was performed. The authors believe that twin A tested positive due to vertical transmission.	14 days	Not justified: the type of test performed is not described properly, and it was performed 12 hours after delivery.
#9 Sun et al. 16	China; Henan; Henan Provincial People's Hospital	28	37 weeks	Not informed	9/9	Cesarean	Obstetricians, anesthesiologists, neonatologists, and nurses wore full personal protective equipment, including an N95 mask, eye goggles, face shield, and a top-to-bottom tight-fitting gown, entering the operating theaters ∼ 5 minutes before the patients. Neonate tested positive for SARS-CoV-2 at day 6 postpartum.	9 days of maternal symptoms + 6 postnatal days	Not justified: RT-PCR in the oropharynx swab collected 12 hours after delivery.

Abbreviations: IgG, immunoglobulin G; IgM, immuniglobulin M; NR, not reported; RT-PCR, real-time polymerase chain reaction; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.