Worsening Maternal Laboratory Abnormalities in Preeclampsia as Predictors of Adverse Neonatal Outcomes

Purpose: This study assesses neonatal outcomes among pregnant patients with preeclampsia by comparing groups based on severity of laboratory abnormalities. Methods: A retrospective chart review was conducted on all neonates born to women with preeclampsia at a tertiary care center between 2015–2020. Preeclampsia was diagnosed according to the guidelines of the American College of Obstetricians and Gynecologists. Data from mother-infant groups were collected retrospectively from the electronic medical record (EMR) and included maternal demographics, laboratory values, delivery details, and neonatal outcomes. Maternal laboratory values assessed included liver enzymes (LE), lactate dehydrogenase (LDH), and creatinine (Cr), which were categorized based on severity: liver enzymes were classified as >2 times the upper limit of normal (>2x ULN) vs. ≤2x ULN, creatinine as >1.1 mg/dL vs. ≤1.1 mg/dL, and lactate dehydrogenase as >600 U/L vs. ≤600 U/L. Neonatal outcomes and delivery variables included gestational age (GA), birth weight, length of neonatal intensive care unit (NICU) stay, overall length of hospital stay (LOS), presence of respiratory distress syndrome (RDS), transient tachypnea of the newborn (TTN), sepsis, infant death (including stillbirths), and mode of delivery (cesarean section, vaginal, or assisted vaginal). Statistical analyses were performed to compare outcomes between groups based on maternal laboratory values, with Chi-square tests to assess differences in the incidence of RDS, TTN, sepsis, death, and mode of delivery. Independent t-tests were performed to compare GA, birth weight, and LOS between groups. These statistical analyses allowed for the evaluation of associations between maternal laboratory abnormalities and neonatal and delivery outcomes. Results: A total of 630 mother-infant groups were included in the study, consisting of 581 singletons, 48 twin pregnancies, and one triplet pregnancy. Compared to patients with liver enzyme (LE) levels ≤2x ULN (n = 563), neonates born to mothers with LE >2x ULN (n = 60) had significantly poorer outcomes. These neonates were born at significantly earlier gestational ages (33.9 vs. 35.8 weeks, p < 0.0001), had lower birth weights on average (2088.2 vs. 2533.4 grams, p < 0.0001), experienced longer neonatal intensive care unit (NICU) stays overall (24.8 vs. 16.0 days, p = 0.0097), and had a higher incidence of RDS (43% vs. 30%, p = 0.038). Similar trends were observed in neonates born to mothers with creatinine (Cr) levels >1.1 mg/dL (n = 58) compared to those with Cr ≤1.1 mg/dL (n = 572). These neonates were also born at earlier gestational ages than their counterparts (33.8 vs. 35.8 weeks, p < 0.0001), had lower birth weights (2161.8 vs. 2525.7 grams, p = 0.0008), stayed in the NICU for a longer duration (23.1 vs. 16.2 days, p = 0.045), and had a higher incidence of RDS (45% vs. 31%, p = 0.022). The most pronounced differences were observed in neonates born to mothers with lactate dehydrogenase (LDH) levels >600 U/L (n = 10) compared to those with LDH ≤600 U/L (n = 552). These neonates had the lowest gestational ages at birth (32.7 vs. 35.4 weeks, p = 0.0085), the lowest birth weights (1736.4 vs. 2480.0 grams, p = 0.0035), the longest NICU stays (40.3 vs. 16.8 days, p = 0.0045), and the highest incidence of RDS (73% vs. 32%, p = 0.0039). Conclusions: Our study suggests that neonates born to preeclamptic mothers with worsening laboratory parameters are at increased risk of adverse neonatal outcomes, including earlier gestational age at delivery, lower birth weights, longer NICU stays, and increased incidence of RDS. Our study confirms that worsening laboratory criteria, which is a marker for preeclampsia with severe features, might be a predictor of those patients who are not candidates for expectant management, leading to worse neonatal outcomes, mostly driven by gestational age at delivery.