Effect of pregnancy on median and ulnar nerve conduction

Sapana S. Motewar, Narendra P. Bachewar


Background: Pregnancy causes altered function of excitable membranes such as muscle and nerve, due to hormonal changes and edema. We failed to find any studies focusing on the issue of nerve conduction during pregnancy, in India. Thus present study aims to see the difference between nerve conduction parameters viz. motor and sensory conduction, in pregnant and non-pregnant women.

Methods: This was a cross-sectional study carried out in randomly selected 30 pregnant women, of any age, in 28-40 weeks of gestation and age matched non-pregnant controls. We studied distal motor latency, compound muscle action potential amplitude, motor nerve conduction velocity, F-minimum latency, sensory latency, sensory nerve action potential amplitude and sensory nerve conduction velocity in bilateral median and ulnar nerves using Aleron-RMS.

Results: Present study found no statistically significant difference between motor and sensory conduction of above said nerves in pregnant and nonpregnant women, except F minimum latency of left median nerve in pregnant women and sensory latency of left ulnar nerve in non-pregnant women were prolonged significantly (p<0.05).

Conclusions: All motor and sensory parameters of bilateral median and ulnar nerves were normal as compared to non-pregnant controls.


CMAP, Carpal tunnel syndrome, Neurophysiology, Sensory latency, SNAP

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