Table 1.

Maternal and neonatal characteristics from published studies (only case for which newborn were tested for SARS-CoV-2 have been reported). If some samples are not mentioned, they have been considered as not performed.

	Liu et al. [16]	Wang X et al. [17]	Zhu H et al. [27]	Yu N et al. [18]	Zeng et al. [28]	Breslin et al. [29]	Wang S et al. [19]	Zeng H et al. [30]	Dong et al. [31]	Yang P et al. [32]	Liu W et al. [33]	Alzamora et al. [34]	Yan et al. [35]	TOTAL
Number of mother infant pairs	3	1	8	3	33	18	1	6	1	7	19	1	NS	101
Gestational age at infection – Mean (WG,days)	38	30	39,4	38,3	NS	37	40	3d trim	34,2	36,4	NS	32,3	38j	38 WG
Positive maternal RT-PCR in nasopharyngeal swab	3	1	7c	3	33	18	1	6	1	7	10 h	1	NS	–
Positive maternal RT-PCR in feces	1a	NP	NP	NP	NP	NP	NP	NP	NP	NP	NP	NP	NP	1/2 (50%)
Positive maternal RT-PCR in vaginal swab	0a	NP	NP	NP	NP	NP	NP	NP	0	NP	NP	NP	0j,k	0/3 (0%)
Positive maternal RT-PCR in breast milk	0a	NP	NP	NP	NA	NP	0	NP	0	NP	0 i	NP	0j,l	0/26 (0%)
Gestational age at delivery (WG,days)	394	31	35,5	39,2	37,2g	NS	40	NS	37,6	37	38,6	33	38,4j	38,3 WG
Infection to delivery interval days - mean (range)	8,3	6	1,4d	4,8	1g	NS	0	NS	25	2,4	4	4	2,5j	3 (0, 25)
Number of newborn	3	1	9e	3	33	18	1	6	1	7	19	1	86	179
Suspected materno-foetal infection (Neonatal RT-PCR or IgM positive for SARS-Cov-2)	0	0	0	1	3	0	1	2	1	0	0	1	0	9 (5%)
Positive neonatal RT-PCR in amniotic fluid	NP	0	NP	NP	NP	NP	NP	NP	NP	0	0	NP	0m	0/37 (0%)
Positive neonatal RT-PCR in placenta	0b	0	NP	0f	NP	NP	0	NP	NP	NP	NP	NP	NP	0/4 (0%)
Positive neonatal RT-PCR in cord blood	0	0	NP	0f	NP	NP	0	NP	NP	0	0	NP	0m	0/48 (0%)
Positive neonatal RT-PCR in nasopharyngeal swab	0	0	0	1	3	0	1	0	0	0	0	1	0	6/179 (3,4%)
Birth to positive neonatal PCR interval (hours)	–	–	–	36	48	–	36	–	–	–	–	16	–	38 hours
Positive IgM for SARS-CoV-2 in newborn	NP	NP	NP	NP	NP	NP	NP	2	1	NP	NP	0	0	3/7 (42%)

NP = not performed / NS = Not stated.

^aOnly two patients were tested.

^bOnly one placenta was tested.

^cThe mother of the twins had typical clinical symptoms, and viral interstitial pneumonia was revealed by a CT scan of her chest. Although her nasopharyngeal swab returned a negative result, other diseases that could cause fever and lung infection were excluded. The local CDC then registered her as a confirmed 2019-nCoV case.

^dOne prelevement was positive 3 days after delivery.

^eOne twin pregnancy.

^fOnly the infected newborn was tested.

^gOnly stated for the 3 positive newborns.

^hOnly ten patients were laboratory-confirmed with COVID-19. According to the study, a clinically diagnosed COVID-19 case was defined as a case of pneumonia that fullfilled the following four criteria – fever and/or respiratory symptoms; radiographic evidence of typical viral pneumonia (bilateral ground-glass opacities); low or normal white-cell count or low lymphocyte count; and no improvement in symptoms after antimicrobial treatment for 2 days, ruling out common virus infection like influenza with or without an epidemiologic link to the Huanan Seafood Wholesale Market or contact with other patients with similar symptoms.

ⁱOnly ten breast milk samples from mothers were performed.

^jClinical characteristics and laboratory findings are mentioned for 99 patients, while only 86 newborns were tested for SARS-CoV-2.

^kOnly six mothers were tested.

^lOnly twelve mothers’ breast milk were tested.

^mOnly ten patients were tested.