JMIR Publications

ABSTRACT

Background:

Both COVID-19 and pregnancy are associated with hypercoagulability. Due to increased risk for thrombosis, the National Institute of Health's recommendation for prophylactic anticoagulant use for pregnant patients has expanded from patients hospitalized for severe COVID-19 manifestation to all patients hospitalized for the manifestation of COVID-19 (no guideline: ~2020/12/26, first update: 2020/12/27~2022/02/23, second update: 2022/02/24~present). However, no study has evaluated this recommendation.

Objective:

The objective of this study was to characterize prophylactic anticoagulant use among hospitalized pregnant people with COVID-19 from 03/20/2020-10/19/2022.

Methods:

This was a retrospective cohort study in large US healthcare systems across seven states. Our cohort of interest was pregnant patients who were hospitalized with COVID-19, without prior coagulopathy or contraindication to anticoagulants (n=2,767). The treatment group consisted of patients prescribed prophylactic dose anticoagulation during -2~+14 days from COVID-19 treatment onset (n=191). The control group was patients with no anticoagulant exposure during -14~+60 days of the SARS-CoV-2 infection date (n=2,534). We ascertained the use of prophylactic anticoagulants with attention to the updates in guidelines and emerging SARS-CoV-2 variants. We propensity score matched the treatment and control group 1:1 on the most important features contributing to the prophylactic anticoagulant administration status classification. Outcome measures included coagulopathy, bleeding, COVID-19-related complications, and maternal-fetal health outcomes.

Results:

The overall administration rate of prophylactic anticoagulants was 7.0% (191/2,725). It was lowest after the second guideline update (no guideline: 10.4%, first update: 9.0%, second update: 2.5%; P<.05) and during the omicron-dominant period (WT:8.3%, Alpha:14.0%, Delta:16.6%, Omicron:3.5%; P<.05). In models developed on retrospective data, having comorbidities prior to SARS-CoV-2 infection was the most important feature for classifying which patients who received inpatient prophylactic anticoagulant. The treatment group was more likely to receive supplementary oxygen (33.0% versus 4.8%; P<.05) than the matched control group. There was no statistical difference in coagulopathies, bleeding, and maternal-fetal health outcomes between the treatment and matched control group.

Conclusions:

Most hospitalized pregnant COVID-19 patients did not receive prophylactic anticoagulants as guidelines recommended. Despite worse COVID-19 illness severity among the treatment group, the treatment group did not have an increased risk of coagulopathy, bleeding or adverse maternal-fetal health outcomes.