Neurodevelopmental Outcomes in Neonates Surviving Fetomaternal Hemorrhage Compared with a Matched Unexposed Group in a Large Integrated Health Care System.

Objective:  This study aimed to assess short-term neurodevelopmental outcomes for neonates affected by fetomaternal hemorrhage (FMH) and compare them with an unexposed group.

Study design:  A retrospective cohort analysis was conducted within a large integrated medical system spanning from 2008 to 2018. Neurodevelopmental outcomes of neonatal survivors of FMH were compared with matched controls. Clinically significant FMH in survivors was defined by maternal flow cytometry for fetal hemoglobin result of >0.10% and neonatal transfusion requirement. One unexposed infant was identified for each surviving FMH-exposed infant, matched by gestational age at delivery (±1 week), birth year, sex, and race/ethnicity. The primary outcome was a diagnosis of neurodevelopmental impairment, identified using the International Classification of Diseases (ICD), 9th and 10th Revisions (ICD-9 and ICD-10) codes. Results were presented as proportions, means, medians, and interquartile ranges. Comparisons were performed using chi-square and Fisher's exact tests. A Cox proportional hazards regression model was conducted to examine associations between cognitive and developmental outcomes and FMH exposure.

Results:  Among 137 pregnancies with clinically significant FMH, 80 resulted in intrauterine demise, 57 neonates required blood transfusion, and 4 neonates requiring transfusion demised during birth hospitalization. No significant difference in rates of neurodevelopmental impairment was found between FMH-exposed and unexposed infants (26.4 vs. 24.6%, p = 0.8). Similar findings were observed in preterm (37 vs. 31.6%, p = 0.7) and term neonates (15.4 vs. 14.8%, p = 1.0). Cox regression showed no significant association between neurodevelopmental outcomes and FMH exposure (1.17 [95% CI: 0.61-2.22]; p = 0.6).

Conclusion:  Despite the significant perinatal morbidity and mortality associated with FMH, surviving infants did not show a significant difference in neurodevelopmental diagnoses compared to matched unexposed infants. However, definitive conclusions are limited due to the rarity of FMH requiring transfusion and the small exposed sample size, warranting further evaluation in a larger cohort.

Key points: · FMH is associated with profound fetal and neonatal morbidity and mortality.. · Impact on neurologic development for infants surviving FMH is unknown.. · Neurodevelopmental outcomes did not differ between survivors of FMH compared to matched controls..