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Risk factors for obstetric brachial plexus palsy among neonates delivered by vacuum extraction
Margareta Mollberg1, Henrik Hagberg, Börje Bager
1Perinatal Center, Department of Obstetrics and Gynecology, Institute for the Health of Women and Children, Sahlgrenska University Hospital, S-416 85 Göteborg, Sweden. margareta.mollberg@vgregion.se
Insights
Instrumental delivery, particularly vacuum extraction, increases the risk of obstetric brachial plexus palsy (OBPP). Shoulder dystocia and longer vacuum extraction times are significant risk factors for OBPP in newborns.
Area of Science:
- Obstetrics and Gynecology
- Neonatal Neurology
- Perinatal Medicine
Background:
- Instrumental vaginal deliveries, including vacuum extraction, are associated with an elevated risk of obstetric brachial plexus palsy (OBPP).
- Identifying specific risk factors is crucial for mitigating OBPP incidence during operative vaginal deliveries.
Purpose of the Study:
- To identify risk factors for obstetric brachial plexus palsy (OBPP) in infants delivered via vacuum extraction.
- To evaluate the association between the duration of vacuum extraction and the risk of OBPP.
Main Methods:
- A population-based retrospective study analyzed 13,716 deliveries using vacuum extraction.
- Univariate and multiple logistic regression analyses were performed on data from a national registry, assessing variables like shoulder dystocia, birth weight, and vacuum application time.
Main Results:
- Obstetric brachial plexus palsy (OBPP) occurred in 1.1% of infants.
- Significant risk factors for OBPP included shoulder dystocia (OR 16.0), fetal birth weight ≥3,999g (OR 7.1), and fundal pressure (OR 1.6).
- The risk of OBPP increased proportionally with the duration of vacuum extraction.
Conclusions:
- Shoulder dystocia is a primary risk factor for OBPP in vacuum-assisted deliveries.
- Prolonged vacuum extraction time is directly associated with an increased risk of obstetric brachial plexus palsy.
Objective:
The risk of obstetric brachial plexus palsy (OBPP) is increased in infants delivered instrumentally. The aim of this study was to identify risk factors for OBPP and to evaluate the association between possible risk factors linked to the duration of the vacuum extraction procedure and the subsequent risk.
Methods:
A population-based retrospective design was adopted. Using a national registry of operative vaginal deliveries linked to the Medical Birth Registry in Sweden, we evaluated by univariate and multiple logistic regression analyses the risk factors for OBPP in 13,716 women delivered by vacuum extraction. The variables assessed in the multiple logistic regression analysis were shoulder dystocia, fetal birth weight of 3,999 g or greater, fundal pressure, number of tractions, vacuum application time, parity, vacuum silicone cup, epidural anesthesia, and fetal head at the level of the ischial spines at vacuum application time.
Results:
Obstetric brachial plexus palsy was recorded in 153 (1.1%) infants. The following variables increased significantly the risk of OBPP in the newborn: shoulder dystocia (odds ratio 16.0; 95% confidence interval 8.9-28.7), fetal birth weight of 3,999 g or greater (7.1; 4.8-10.5), and administration of fundal pressure (1.6; 1.1-2.3). The probability of the risk of OBPP in vacuum-assisted deliveries increased in relation to vacuum extraction time (minutes).
Conclusion:
Shoulder dystocia in the setting of vacuum extraction is a prominent risk factor for OBPP in the newborn. The risk of OBPP increases with the time required for vacuum extraction.
Level Of Evidence:
II-3.
