Impact of Parity on Time to Diagnosis and Treatment of Brachial Plexus Birth Palsy

Background: Although 2 out of every 1000 babies are born with brachial plexus palsy, few studies have investigated the effect of gravida on brachial plexus palsy incidence. The purpose of this study was to evaluate the relationship between brachial plexus palsy at birth, parity, and subsequent treatment.

Methods: A retrospective review of 163 patients who presented to our clinic between January 1, 2005 and January 1, 2015 for treatment of brachial plexus birth palsy. Data was collected regarding the birth history and subsequent surgical treatment for brachial plexus birth palsy.

Results: 163 patients presented to a tertiary pediatric medical center between January 1, 2005 and January 1, 2015. 39% (64/163) of these patients were born to primiparous women while 61% (99/163) were born to multiparous women. Children born to multiparous women had a statistically significant higher birth weight (4.158 kg vs. 3.837 kg, p=0.0020), greater incidence of dystocia (31.4% vs. 17.2%, p=0.038), and earlier time to first presentation for treatment (3.45 months vs. 15.07 months, p=0.0055). In addition, children born to multiparous women on average had a significantly lower need for multiple surgeries for the treatment of their brachial plexus palsy compared to those of primiparous women (4.9% vs. 7.3%, p=0.043).

Conclusion: Compared to those of primiparous women, children born to multiparous women have higher known risk factors for brachial plexus birth injury such as shoulder dystocia and large gestational size. However, the prevalence of brachial plexus birth injury among first-born children underscores the importance of educating all mothers about the risk factors for brachial plexus palsy to reduce the disparity in time to first presentation for treatment, and number of surgeries, between children born to multiparous and primiparous mothers.