(685) Wild type through Omicron: Obstetric outcomes across COVID-19 waves

SARS-CoV-2 has been associated with poor obstetrical outcomes, however few studies specifically compare these outcomes across the waves of the pandemic. We sought to determine if obstetrical outcomes differed across COVID-19 waves.

Study Design:

Retrospective study of pregnant patients with SARS-CoV-2 between 3/6/20 and 2/28/22 at a single academic center. Three distinct waves of the pandemic were identified that correlated to the following variants: Wild type (3/6/20-12/31/20), Alpha/Delta (1/1/21-12/14/21), and Omicron (12/15/21-2/28/22). Baseline demographics and perinatal outcomes were collected. The primary outcome was a composite of obstetric complications (PPH, IUFD, PTL, blood transfusion, pyelonephritis, GDM, and PPROM). Statistical analysis was performed using Chi square tests, student T-tests, and logistic regression modeling, with statistical significance defined as p< 0.05.

Results:

There were 654 patients included in the analysis with 190 (29%) patients in the wild type wave, 207 (31%) patients in the Alpha/Delta wave, and 257 (39%) patients in the Omicron wave. Baseline demographics are shown in Table 1. Alpha/Delta and Omicron waves had statistically significant higher odds of obstetrical complications compared to wild type (OR 2.00; 95% CI 1.31-3.08). The incidence of preeclampsia with severe features varied from 6.3% during wild type versus 1.4% during Alpha/Delta versus 5.1% during Omicron waves (p < 0.026). Patients with multifetal gestation had significant lower odds of obstetric complications (OR 0.16; 95% 0.06-0.43). Patients that had no hospitalization had significantly higher odds of obstetric complications (OR 2.77; 95% CI 1.08-7.09). Rates of other obstetric complications are shown in Figure 1.

Conclusion:

Obstetric complications varied across COVID waves with a higher risk in the Alpha/Delta and Omicron waves compared to the wild type wave. The risk of preeclampsia with severe features was higher in the wild type and Omicron waves compared to the Alpha/Delta wave. Multifetal gestation had a protective effect for developing obstetric complications.