384 - Multiparity as Determinant of Death and/or Neuro-Morbidity in Preterm Infants

Publication Number: 384.5908

Kulsajan S. Bhatia, University of Alabama School of Medicine, Bimringham, AL, United States; Mithun Kumar Acharjee, University of Alabama at Birmingham, Memphis, TN, United States; AKM F. Rahman, The University of Alabama, Birmingham, Birmingham, AL, United States; Jegen Kandasamy, University of Alabama at Birmingham, BIRMINGHAM, AL, United States; Colm P. Travers, UAB, Birmingham, AL, United States; Waldemar Carlo, UAB School of Medicine, Birmingham, AL, United States; Namasivayam Ambalavanan, University of Alabama School of Medicine, Birmingham, AL, United States; Vivek Shukla, University of Alabama at Birmingham, Birmingham, AL, United States

Background: Multiparous pregnancy is frequently associated with the birth of extremely low birth weight (ELBW) infants, and its incidence is on the rise due to the increased use of assisted reproduction techniques. Whether multiparity is independently associated with adverse neuro-morbidity compared to singleton births in ELBW infants remains unknown.

Objective: This study aimed to determine if multiparity is associated with increased neuro-morbidity in comparison to singletons in infants born between 21-27 weeks gestational age (GA).

Design/Methods: We included 2440 ELBW infants born between 22 0/7 to 27 6/7 weeks GA at the University of Alabama at Birmingham Neonatal Unit between 1998 to 2022. Infants with multiple anomalies were excluded. The primary outcome was death and/or severe neuro-morbidity (which was defined as ventricular hemorrhage resulting in ventricular enlargement, intraparenchymal cerebral hemorrhage, and/or cystic periventricular leukomalacia by 1-month after birth). Individual probabilities of death or severe neuro-morbidity were included as secondary outcomes. Binary logistic regression (with sex, GA, and birth weight included as co-variates) was used to compute the absolute change in outcome probabilities between multiparous births vs singletons during each week of GA. All statistical analyses were performed using R (Version 4.3.1), with P < 0.05 considered significant.

Results: The baseline characteristics (Table 1) varied as expected among groups. Lower GA was associated with higher probabilities of death and/or neuro-morbidity (Figures 1 and 2). The difference in probabilities between singleton and multiple births was not significant (p-value = 0.326). Notably, although multiples have a slightly higher probability of death and/or neuro-morbidity than singletons across all gestational ages, the gap is minimal. This implies that while multiparity may have some impact, gestational age is a more influential predictor of studied outcomes in our cohort. The close alignment of the red and blue lines highlights that, after adjusting for other factors, the effect of multiparity is relatively modest.

Conclusion(s): These figures suggest that multiparity may be associated with a higher risk of adverse outcomes (both death with neuro-morbidity and neuro-morbidity alone) in extremely preterm neonates, particularly at lower gestational ages. However, the effect of multiparity on risk appears to decrease with increasing gestational age, potentially highlighting gestational age as a significant mitigating factor.

Baseline characteristics for outcome groups
Baseline characteristics for outcome groups

This plot shows the relationship between gestational age (in weeks) and the predicted probability of death and/or neuro-morbidity, separated by multiparity status. The x-axis represents gestational age, ranging from 21 to 27 weeks, and the y-axis indicates the probability of death. The blue line represents single births ("Multiparity: No"), while the red line represents twin births ("Multiparity: Yes").
This plot shows the relationship between gestational age (in weeks) and the predicted probability of death and/or neuro-morbidity, separated by multiparity status. The x-axis represents gestational age, ranging from 21 to 27 weeks, and the y-axis indicates the probability of death. The blue line represents single births ("Multiparity: No"), while the red line represents twin births ("Multiparity: Yes").

Spline representation of neuro-morbidity showing relationship between singleton vs multiparity.
Spline representation of neuro-morbidity showing relationship between singleton vs multiparity.