Head injuries related to birth trauma among low birthweight neonates
during vacuum extraction: a retrospective cohort study
Abstract
Objective: Prematurity [gestational age (GA)<34w]
is a relative contraindication to vacuum extraction (VE). Current data
do not discriminate clearly between prematurity and low-birthweight
(LBW). We aimed to evaluate the impact of non-metal vacuum cup
extraction on neonatal head injuries related to birth-trauma (HI), among
newborns with LBW (<2,500g). Design: A retrospective
cohort. Population: 3,335 singleton pregnancies, delivered by
VE from 2014 to 2019. All were >34w GA. Methods:
We compared 207 (6.2%) neonates with LBW <2,500g to 3,128
(93.8%) neonates with higher BW, divided into 3 subgroups
(2,500-2,999g, 3,000-3,499g, and >3,500g). Main
outcome measures: HI and other neonatal complications.
Results: The lowest rates of subgaleal hematoma occurred in
neonates <2,500g (0.5%) and increased with every additional
500g of neonatal birthweight (3.2%, 4.4% and 7.6% in 2,500-2,999g,
3,000-3,499g, and >3,500g groups, respectively; p=0.001).
Fewer cephalohematomas occurred among LBW neonates (0.5% in
<2,500g) and increased with every additional 500g of
birthweight (2.6%, 3.3% and 3.8% in 2,500-2,999g, 3,000-3,499g, and
>3,500g groups, respectively, p=0.026). Logistic regression
found increasing birthweight as a significant risk-factor for head
injuries during VE, with adjusted odds ratios of 8.874, 10.624, 13.980
for 2,500-2,999g, 3,000-3,499g, and >3,500g, respectively
(p=0.015). NICU hospitalization rates were highest among neonates
weighing <2,500g (10.1%) compared to the other groups (2.7%,
1.7% and 3.3% in 2,500-2,999g, 3,000-3,499g, >3,500g
respectively, p=0.000). Conclusions: VE of neonates weighing
<2500g at 34w and beyond seems as a safe mode of delivery when
indicated, with lower rates of HI, compared to neonates with higher BW.
Funding: none.