Supplemental Digital Content 2: Antibody levels at delivery and 6 weeks in maternal blood, infant blood, and breastmilk after COVID-19 infection in pregnancy
Sample Type
Antibod y
Delivery Mean (SD)+
6 weeks Mean (SD)+
Mean Difference (95% CI)*
P-Value
Spike Protein Maternal blood
IgG 22527.1
(42791.0)
81528.7 (161908.6)
56971.3 (-6928.6, 120871)
0.08
IgM 2753.3
(3512.3)
2529.3 (422.5)
-229.0 (-1523.4, 1065.5)
0.72
IgA 1302.0
(1735.9)
3284.0 (5845.0)
1843.5
(-417.2, 4104.2)
0.11 Infant / cord
blood
IgG 17638.0
(37849.8)
4397.1 (4564.2)
-21178.0 (-45262.3, 2906.4)
0.08
IgM 107.6
(382.4)
25.4 (42.0)
-168.7
(-449.1, 111.7)
0.22
IgA 65.5
(236.9)
352.6 (1164.5)
251.5
(-200.7, 703.7)
0.26 Breast milk IgG 150.6
(385.3)
2602.7 (11048.8)
263.0
(-779.9, 1305.9)
0.58
IgM 409.3
(837.0) 145.5
(503.5) -568.2
(-1384.0, 247.5) 0.15
IgA 2198.1
(2197.7) 1935.1
(2463.7) 550.6
(-857.2, 1958.4) 0.42 Nucleocapsid Protein
Maternal blood
IgG 293728.2
(497515.8)
358871.9 (438150.2)
18590.8 (-100338, 137519)
0.75
IgM 6206.6
(1415.2)
8727.2 (22452.6)
1956.1 (-2989.7, 6901.9)
0.42
IgA 9182.4
(17297.0)
25943.7 (104935.8)
17714.4 (- 20107.1, 55535.8)
0.34
Infant / cord blood
IgG 310041.8 (697422.6)
313661.7 (915379.7)
-98510.7 (-780716, 583694)
0.76
IgM 651.2
(2214.9) 108.3
(84.8) -1083.4
(-2671.7, 504.9) 0.17
IgA 213.7
(384.0)
156.67 (388.9)
-138.3
(-434.1, 157.5)
0.34
Breast milk IgG 159734.1 82158.9 -140474 (- 0.17
(319749.5) (130726.0) 356074, 75127.2)
IgM 1458.8
(1919.0) 168.2
(259.7) -1687.9
(-3289, -86.8) 0.04
IgA 35125.5
(31996.0)
4459.0 (5626.4)
-35083.3 (- 59151.9, -11014.7)
0.009
*Delivery time point used as reference +All values reported as AU
