The Impact of Pregnancy on Diabetic Retinopathy: a Single-Center Study of Clinical Risk Factors

Introduction: This study aimed to provide information on modifiable and non-modifiable risk factors for the progression and development of diabetic retinopathy (DR) and diabetic macular edema (DME). This retrospective chart review case-control study was designed to provide perspective on clinical variables.Methods: Single-center study analysis was completed with chart review, identifying 50 patients (100 eyes) ultimately included in the final analysis. Included patients were women with type 1 or 2 diabetes that entered prenatal care and had a delivery from January 2010-December 2022. The primary outcome measure was clinical variables between progression and no progression groups. Data was analyzed via chi-square analysis and independent samples t-test when appropriate. Significantly different variables were further analyzed by binary logistic regression.Results: The DR progression group had significantly higher pre-pregnancy HbA1c levels (9.9) when compared to the no progression group (8.5, p-val 0.028). DR progression group also had higher rates (51.9%) of full-term births. The DME progression group had significantly higher rates of Type 2 diabetics (100%) compared to the no progression group (30.9%, p-val 0.029). Hypertension treatment before (81.8%; p-val 0.008) pregnancy was also more common in the DME progression group. Intravitreal injections were more common in patients with visual acuity deterioration (26.7%, p-val 0.046). The average number of fetal complications was significantly higher in the VA non-worsening group (1.1) compared to the progression group (0.5, p-val 0.04). These variables were not statistically significant after entry into multivariate analysis.Discussion: Severity and treatment of retinopathy before pregnancy, type of diabetes, and blood pressure control are all significant factors affecting the progression and development of severe ocular complications in pregnancy.