TABLE 1.
Demographics of pregnant people with SARS-CoV-2 infection by variant predominance period
| Total N (%) | Pre-delta, n (%) (March 3, 2020 - June 26,2021) | Delta, n (%) (June 27-Dec. 25, 2021) | ||
|---|---|---|---|---|
| Totala | 56,856 (100.0) | 38,828 (68.3) | 18,028 (31.7) | |
| Age | (Median, IQR) | 29.5 (25.3–33.4) | 29.5 (25.3–33.3) | 29.5 (25.1–33.4) |
| <20 y | 2760 (4.9) | 1798 (4.6) | 962 (5.3) | |
| 20–24 y | 10,720 (18.9) | 7239 (18.6) | 3481 (19.3) | |
| 25–29 y | 16,991 (29.9) | 11,803 (30.4) | 5188 (28.8) | |
| 30–34 y | 16,839 (29.6) | 11,484 (29.6) | 5355 (29.7) | |
| 35–39 y | 7912 (13.9) | 5353 (13.8) | 2559 (14.2) | |
| 40+y | 1615 (2.8) | 1138 (2.9) | 477 (2.6) | |
| Unknown | 19 (0.0) | 13 (0.0) | 6 (0.0) | |
| Race/ethnicity | American Indian or Alaska Native | 323 (0.6) | 207 (0.5) | 116 (0.6) |
| Asian non-Hispanic | 1943 (3.4) | 1510 (3.9) | 433 (2.4) | |
| Black non-Hispanic | 8524 (15.0) | 5840 (15.0) | 2684 (14.9) | |
| Hispanic/Latino | 11,483 (20.2) | 9195 (23.7) | 2288 (12.7) | |
| Native Hawaiian or Other Pacific Islander | 168 (0.3) | 117 (0.3) | 51 (0.3) | |
| Other race non-Hispanic | 1057 (1.9) | 706 (1.8) | 351 (1.9) | |
| White non-Hispanic | 31,477 (55.4) | 19,864 (51.2) | 11,613 (64.4) | |
| Unknown | 1881 (3.3) | 1389 (3.6) | 492 (2.7) | |
| Insurance status at delivery | Medicaid | 25,237 (44.4) | 18,384 (47.3) | 6853 (38.0) |
| Private | 22,482 (39.5) | 14,709 (37.9) | 7773 (43.1) | |
| None/self-pay | 712 (1.3) | 469 (1.2) | 243 (1.3) | |
| Other | 674 (1.2) | 474 (1.2) | 200 (1.1) | |
| Missing/not reported | 7751 (13.6) | 4792 (12.3) | 2959 (16.4) | |
| Trimester of infection | First trimester | 14,702 (25.9) | 10,158 (26.2) | 4544 (25.2) |
| Second trimester | 19,201 (33.8) | 12,839 (33.1) | 6362 (35.3) | |
| Third trimester | 22,953 (40.4) | 15,831 (40.8) | 7122 (39.5) | |
| Trimester of prenatal care initiationb | First trimester | 42,624 (74.0) | 29,326 (74.5) | 13,298 (73.0) |
| Second trimester | 8404 (14.6) | 5912 (15.0) | 2492 (13.7) | |
| Third trimester | 1550 (2.7) | 1056 (2.7) | 494 (2.7) | |
| Unknown trimester | 3137 (5.4) | 1820 (4.6) | 1317 (7.2) | |
| No prenatal care | 1034 (1.8) | 630 (1.6) | 404 (2.2) | |
| Unknown | 814 (1.4) | 597 (1.5) | 217 (1.2) | |
| Parity | Nulliparous | 12,563 (22.1) | 8564 (22.1) | 3999 (22.2) |
| Multiparous | 32,679 (57.5) | 21,597 (55.6) | 11,082 (61.5) | |
| Unknown | 11,614 (20.4) | 8667 (22.3) | 2947 (16.3) | |
| Underlying health conditions | Any underlying condition | 20,825 (36.6) | 13,937 (35.9) | 6888 (38.2) |
| Pre-pregnancy obesity | 16,214 (28.5) | 10,546 (27.2) | 5668 (31.4) | |
| Pre-pregnancy diabetes | 898 (1.6) | 634 (1.6) | 264 (1.5) | |
| Chronic hypertension | 2099 (3.7) | 1407 (3.6) | 692 (3.8) | |
| Chronic lung disease | 1524 (2.7) | 1171 (3.0) | 353 (2.0) | |
| Cardiovascular disease | 498 (0.9) | 393 (1.0) | 105 (0.6) | |
| Renal disease | 95 (0.2) | 72 (0.2) | 23 (0.1) | |
| Liver disease | 362 (0.6) | 234 (0.6) | 128 (0.7) | |
| Autoimmune condition | 237 (0.4) | 186 (0.5) | 51 (0.3) | |
| Immunosuppressive condition | 301 (0.5) | 249 (0.6) | 52 (0.3) | |
| Disability | 62 (0.1) | 49 (0.1) | 13 (0.1) | |
| Pregnancy complications | Gestational diabetes | 5309 (9.3) | 3798 (9.8) | 1511 (8.4) |
| Pregnancy-induced hypertensionc | 5151 (9.1) | 3493 (9.0) | 1658 (9.2) | |
| Vaccination status at first infection in pregnancy | 0 doses | 52,727 (92.7) | 38,589 (99.4) | 14,138 (78.4) |
| 1 dose | 895 (1.6) | 107 (0.3) | 788 (4.4) | |
| 2 doses | 3079 (5.4) | 92 (0.2) | 2987 (16.6) | |
| 3 doses | 72 (0.1) | 2 (0.0) | 70 (0.4) | |
| 4 doses | 5 (0.0) | 0 (0.0) | 5 (0.0) | |
| Unknown timing | 78 (0.1) | 38 (0.1) | 40 (0.2) | |
| Days since last vaccinationd | (Median, IQR) | 176 (100–229) | 32 (22 –65) | 183 (113–231) |
| Deathe | Yes | 29 (0.51/1000 pregnant persons) | 16 (0.41/1000 pregnant persons) | 13 (0.72/1000 pregnant persons) |
| No | 39,080 (68.7) | 27,523 (70.9) | 11,557 (64.1) | |
| Unknown | 17,747 (31.2) | 11,289 (29.1) | 6458 (35.8) |
IQR, interquartile range.
a
Row percent for total; remaining table includes column percent.;
b
Trimester of prenatal care initiation was calculated from last menstrual period to first prenatal care visit.;
c
Includes preeclampsia.;
d
Last doses defined as last vaccination date greater than 14 days from infection. The majority of infections in the Delta cohort were vaccinated January to May of 2021 and were infected later in the Delta period (August-December 2021).;
e
Death included deaths during pregnancy, at pregnancy outcome, and upto and including 42 days after outcome.