Association of in vitro fertilization with severe maternal morbidity in low-risk patients without comorbidities.

ABSTRACT

OBJECTIVE: To determine whether an association exists between in vitro fertility (IVF) and severe maternal morbidity among low-risk pregnant patients. DESIGN: Retrospective cohort study SUBJECTS: Low-risk pregnant patients who delivered between 1/2019 and 12/2022. Low-risk was defined as having an Obstetric Comorbidity Index (OB-CMI) score of 0. EXPOSURE IVF MAIN OUTCOME MEASURES: The primary outcome (dependent variable) was any severe maternal morbidity. The secondary outcome was the need for a cesarean delivery. A modified Poisson regression with robust error variance was used to model the probability of severe maternal morbidity as a function of IVF. Risk ratios (RR) and their associated 95% confidence intervals (CI) were computed. An alpha value of 0.05 was considered statistically significant. RESULTS: A total of 39,668 pregnancies were included for analysis, and 454 (1.1%) were conceived by IVF. The overall severe maternal morbidity rate was 2.4% (n=949), with the most common indicator being blood transfusion. Overall cesarean delivery rate was 18.8% (n=7,459). On modified Poisson regression, IVF-conceived pregnancies were associated with 2.56 times the risk of severe maternal morbidity (95% CI 1.73 - 3.79) and 1.54 times the risk of having a cesarean delivery (95% CI, 1.37-1.74) compared to non-IVF pregnancies. CONCLUSION: IVF is associated with higher rates of severe maternal morbidity, primarily the need for a blood transfusion, and cesarean delivery in low-risk pregnancies without major comorbidities. Recognizing this association allows healthcare providers to implement proactive measures for better monitoring and tailored postpartum care.