Aplastic anemia in pregnancy: A case series review of hematologic parameters, treatment, and maternal-fetal outcomes

Abstract Introduction: Aplastic anemia (AA) affects approximately 1 in a million people per year in the United States and can present as a new diagnosis, progression, or relapse during pregnancy. Due to the rarity of the disease, there are limited data on its clinical presentation, hematologic parameters, treatment strategies, and maternal-fetal outcomes to guide diagnosis and management. Methods: We conducted a comprehensive literature review using PubMed, Google Scholar, and ScienceDirect to identify peer-reviewed studies published between 2001 and 2024. Articles were selected based on relevance and availability of clinical outcome data. We included cases of AA that were active during pregnancy—newly diagnosed, relapsed, or persistent. Data collected included patient demographics (age, sex), AA status (blood counts, disease severity, timing of presentation, management, and complications), fetal outcomes (gestational age and mode of delivery), and birth complications. Results: A total of 53 cases of AA during pregnancy were identified. Of these, 12 were diagnosed during pregnancy and 11 prior to pregnancy. For the 12 cases that developed during pregnancy, diagnoses were made across all trimesters: first (n=6), second (n=4), and third (n=2). Notably, in one patient, AA was active during the third and fourth pregnancies but not during the first or second, suggesting that AA can present intermittently across pregnancies in the same individual. The timing of diagnosis was unspecified in the remaining 30 cases. The median maternal age at AA diagnosis was 26.5 years (range: 19–38), and the median gestational age at birth was 37 weeks (range: 31–40). Among cases where timing was reported, 21% were diagnosed before pregnancy and 23% during pregnancy. Severity was reported in all 53 cases: 72% were classified as non-severe, 26% as severe, and 2% as very severe. Cesarean section was the primary delivery method in 66% of cases. At the time AA was diagnosed or active during pregnancy, median laboratory values were: hemoglobin 7.3 g/dL (range: 3.0–11.8), platelet count 26 × 10⁹/L (range: 8.0–103), and absolute neutrophil count 1.0 × 10⁹/L (range: 0.4–4.0). Maternal and fetal outcomes were reported in 60% and 59% of cases, respectively. Maternal complications included gestational hypertension (6%), gestational diabetes mellitus (6%), infections (23%), and bleeding (26%). Fetal outcomes were generally favorable, with approximately 57% of infants reported as healthy at birth. However, adverse outcomes such as preterm delivery (19%), intrauterine growth restriction (6%), low birth weight (6%), and neonatal intensive care unit admission (9%) were also observed. Maternal and fetal mortality occurred in 4% and 2% of cases, respectively. Treatments administered during pregnancy included red blood cell transfusions (17%), platelet transfusions (17%), and cyclosporine (15%). In the postpartum period, some patients required additional therapies: antithymocyte globulin (4%), eltrombopag (6%), and hematopoietic stem cell transplantation (8%). Conclusion: Aplastic anemia during pregnancy remains rare and clinically complex, with variable timing, severity, and outcomes. Our review underscores the need for early recognition and multidisciplinary management to reduce risks to both mother and fetus. The observation that AA may occur in some pregnancies but not others within the same individual raises important questions about underlying disease mechanisms. Broader, systematic studies are needed to clarify these patterns and to inform safer, more effective treatment strategies during pregnancy.