Table 1. Cohort Demographic Characteristics.

Maternal and gestational ages were presented as mean ± standard deviation. No significant difference between fetal sex was determined with Fisher’s exact test.

		Vaccinated/Uninfected (n=124)	Breakthrough Infection (n = 25)	Unvaccinated/Infected (n = 16)
Age (years)		34.2 ± 4.1	33.2 ± 3.9	31.4 ± 6.4*
Age Range (years)		25 – 45	25 – 40	19 – 40
Body Mass Index (BMI)		25.5 ± 5.6	26.6 ± 6.5	29.2 ± 8.5**
Gestational Age at Delivery (weeks)		38.9 ± 1.6	38.8 ± 1.6	37.7 ± 1.9*
Sex of Fetus (% Female)		48%	56%	59%
Time of First	Pre-Pregnancy	14	23	0
	T1	17	1	0
	T2	47	1	0
	T3	16	0	1
	Postpartum	30	0	9
	No Vaccine	0	0	6
Time of Boost	Pre-Pregnancy	0	4	0
	T1	1	8	0
	T2	1	2	0
	T3	10	3	0
	Postpartum	82	2	2
	No Boost	30	6	14
Time of	Pre-Pregnancy	0	0	0
	T1	0	6	2
	T2	0	5	8
	T3	0	14	6
	Postpartum	39	0	0
	No Infection	85	0	0
Race	American Indian/ .Alaskan Native	2 (1.6%)	1 (4.0%)	1 (6.25%)
	Asian American	9 (7.3%)	2 (8.0%)	0
	Black/African American	5 (4.0%)	0	1 (6.25%)
	Pacific Islander	0	0	1 (6.25%)
	White/Caucasian	105 (84.7%)	20 (80.0%)	11 (68.75%)
	Unknown/Declined	3 (2.4%)	2 (8.0%)	2 (12.5%)
Ethnicity	Hispanic	4 (3.2%)	1 (4%)	6 (37.5%)
	Non-Hispanic	118 (95.2%)	23 (92%)	10 (62.5%)
	Unknown/Declined	2 (1.6%)	1 (4%)	0
Smoking	Never	111 (89.5%)	21 (84.0%)	14 (87.5%)
	Previous	12 (9.7%)	4 (16.0%)	1 (6.25%)
	Current	1 (0.8%)	0	1 (6.25%)

T1: first gestational trimester (< 13 weeks); T2: second gestational trimester (13 to 26.6 weeks); T3: third gestational trimester (≥ 27 weeks)

^*Maternal age and gestational age within the Unvaccinated/Infected cohort was significantly lower than both the Vaccination/Uninfected and Breakthrough Infection cohorts.

^**BMI within the Unvaccinated/Infected cohort was significantly higher than the Vaccination/Uninfected. No significant difference was determined between the Vaccinated/Uninfected and Breakthrough Infection cohorts for maternal age, gestational age, or BMI.