Table 3.
Cohort or case series studies from outside of China
| Author (country) | Number of women | Number of eligible neonates | GA at onset of Sx or diagnosis (range) | Mode of delivery | RT-PCR for SARS-CoV-2 |
Neonatal serology | Placental histology | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Neonatal NP swab results | Placenta | Cord blood | Amniotic fluid | Other fetal sites or tests | |||||||
| Breslin et al (United States)76 | 43 | 18 | Median GA 37 wk (IQR, 32 wk 4 d–38 wk 6 d) | VD 10, CD 8 | 0/18 positive | None | None | None | None | None | None |
| Breslin et al (United States)77 | 7 | 2 | 26 wk 3 d–37 wk 5 d | CD 2 | 0/2 positive | None | None | None | None | None | None |
| Ferrazzi et al (Italy)78 | 42 | 42 | Third trimester, 30 women >37 wk, 12 women <37 wk | VD 24, CD 18 | 3/42 | None | None | None | None | None | None |
| Penfield et al (United States)79 | 32 | 10 | 26 wk 4 d–41 wk 2 d | VD 7, CD 4 | 0/10 | 1/1 | None | None | Fetal membranes (2/10) | None | None |
| Pierce-Williams et al (United States)80 | 64 | 33 (1 set of twins) | 16 wk 1 d–39 wk 1 d | VD 8/32, CD 24/32 | 1/33 | None | None | None | None | None | None |
| Lokken et al (United States)81 | 46 | 8 | 33 wk 0 d–38 wk 6 d | VD 3, CD 5, | 0/8 | 0/1 (stillbirth) | None | None | Fetal autopsy sites (0/1) | None | Severe chronic villitis but no viral inclusions (1/1) |
| London et al (United States)82 | 68 | 48 | 3 in the second trimester (17 wk, 25 wk, 26 wk), the rest in the third trimester | VD 33, CD 22 | 0/48 | None | None | None | None | None | None |
| Mulvey et al (United States)83 | 5 | 5 | 38–40 wk | VD 4/5, CD 1/5 | N/A | 0/5 | None | None | None | None | Fetal vascular malperfusion (5/5), thrombosis (5/5), intramural fibrin deposition (4/5), meconium (3/5), avascular villi (1/5), villous stromal-vascular karyorrhexis (1/5) |
| Baergen and Heller (United States)84 | 20 | 21 (1 pair of twins) | 32–40 wk | VD 15/20, CD 5/20 | 0/21 | None | None | None | None | None | Fetal vascular malperfusion (9/20), intramural fibrin deposition (3/20), meconium macrophages (6/20), lesions of maternal vascular malperfusion (5/20), ascending infection with acute chorioamnionitis and acute funisitis (1/20), chronic villitis (4/20) |
| Buonseno et al (Italy)85 | 7 | 2 | 8 wk–37 wk 3 d | CD 2/2 | 0/2, on d 15 positive (1/2) | 1/2 | 1/2 | 0/2 | Rectal swab (0/2) | IgM negative (0/1), IgG slightly positive (1/1) | None |
| Govind et al (United Kingdom)86 | 9 | 9 | 27–39 wk | VD 1/9, CD 8/9 | 1/9 | 0/9 | None | 0/9 | None | None | None |
| Knight et al (United Kingdom)12 | 427 | 244 | Median, 34 wk (IQR, 29–38), <22 wk (n=22), 22–27 wk (n=60), 28–31 wk (n=64), 32–36 wk (n=106), 37+ wk (n=142), peripartum (n=30), missing (n=3) | VD 101, CD 144 | 12/244 (6/244 tested positive <12 h, 6/244 tested positive >12 h) | None | None | None | None | None | None |
| Patanè et al (Italy)30 | 22 | 22 | 35–37 wk | VD 1/2, CD 1/2 | 2/22 (1 was negative at birth but turned positive at day 7 without contact with mother) | None | None | None | None | None | Chronic intervillositis in intervillous and the villous space (2/22) |
| Pereira et al (Spain)87 | 60 | 23 | Median GA, 32 wk (range, 5–41 wk) | VD 18/23, CD 5/23 | 0/23 | 0/6 | None | None | None | None | None |
| Shanes et al (United States)88 | 16 | 16 | Second trimester (16 wk), third trimester (34–40 wk) | N/A | 0/16 | None | None | None | None | None | IUFD case pathology showed retroplacental hematoma and villous edema, maternal vascular malperfusion (12/15), central and peripheral villous infarctions (4/15), mural hypertrophy of membrane arterioles (5/15), accelerated villous maturation (2/15) |
| Qadri and Mariona (United States)89 | 16 | 12 | 22–40 wk | VD 8/12, CD 4/12 | 0/12 | None | None | None | None | None | None |
| Vintzileos et al (United States)90 | 32 | 29 | N/A | N/A | 0/29 | None | None | None | None | None | None |
All papers are identified by author, country (unless otherwise specified), and citation number within the main text.
BAL, bronchoalveolar lavage; CD, cesarean delivery; EM, electron microscopy; GA, gestational age; IgG, immunoglobulin G; IgM, immunoglobulin G; IQR, interquartile range; IUFD, intrauterine fetal demise; N/A, not available; NP, nasopharyngeal; RT-PCR, reverse transcription–polymerase chain reaction; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; Sx, symptoms; VD, vaginal delivery.
Kotlyar. Vertical transmission of COVID-19: a systematic review and meta-analysis. Am J Obstet Gynecol 2021.