Factors Associated with Guideline Concordant Clinician Counseling about Low Dose Aspirin to Prevent Preeclampsia in Nulliparous Patients.

OBJECTIVE: The primary aim of this study was to examine USPSTF guideline concordant LDA counseling and factors associated with counseling in nulliparous birthing individuals.

STUDY DESIGN: We conducted a retrospective cohort study of nulliparous birthing individuals who delivered between January 1, 2019, and June 30, 2020, and received prenatal care at the Duke High Risk Obstetrical Clinics (HROB). All nulliparous patients over 18 years old who established or transferred care to HROB by 16 weeks, 6 days were included in the analysis. We excluded patients with more than two previous first-trimester pregnancy losses, multiple gestation, a known contraindication to LDA, initiation of LDA prior to their prenatal care or documented medical history of coagulation disorder. Bivariate associations between demographic/medical characteristics and our primary outcome, receipt of counseling (Yes/No), were assessed using two-sample t-tests for continuous variables and Chi-square or Fisher's exact test for categorical variables. Factors significantly associated with the primary outcome (p < 0.05) were entered into the multivariable logistic regression model.

RESULTS: Among 391 birthing individuals included in the final analysis cohort, 51.7% of eligible patients received guideline consistent LDA counseling. Factors associated with increased odds of LDA counseling were advanced maternal age (adjusted odds ratio [aOR]:1.05, 95% confidence interval [CI]:1.01-1.09), Black race compared to White race (aOR:1.75, 95%CI: 1.03-2.98), chronic hypertension (aOR: 4.17, 95%CI: 1.82-9.55), and obesity (aOR:5.02, 95%CI: 3.12-8.08).

CONCLUSIONS: Approximately half of all nulliparous birthing individuals had appropriately documented LDA counseling. The USPSTF guidelines on LDA for preeclampsia risk reduction are complex, which may lead to ineffective provider adherence. Efforts to simplify guidelines and improve LDA counseling are vital to ensuring this low-cost, evidence-based preeclampsia prevention is used in a consistent and equitable manner.