Electrical impedance measurements: an objective measure of prelabor cervical change.
OBJECTIVE
To investigate the use of electrical impedance measurements of the pregnant cervix as an objective measure of cervical favorability (Bishop score > or = 5).


METHODS
A prospective study of 86 women, investigating electrical impedance measurements of the pregnant cervix at the time of induction of labor. Transfer electrical impedance measurements were made by placing a tetrapolar pencil probe of 8 mm in diameter on the surface of the cervix. A Bishop score was determined simultaneously.


RESULTS
A mean resistivity (standard error of the mean) of 7.03 (6.01-8.04) omega(m) was measured for the unfavorable group and 5.34 (4.61-6.07) omega(m) for the favorable group. This was a statistically significant difference (p = 0.016).


CONCLUSIONS
We highlight the ability of this safe, painless technique to differentiate the favorable from the unfavorable cervix at induction of labor.
O'Connell
M P
MP
Coombe Women's Hospital, Dublin, Republic of Ireland.
Avis
N J
NJ
Brown
B H
BH
Killick
S R
SR
Lindow
S W
SW
D000293:Adolescent; D000328:Adult; D002584:Cervix Uteri / Q000502:physiology*; D017097:Electric Impedance; D005260:Female; D006801:Humans; D007745:Labor Onset / Q000502:physiology*; D007751:Labor, Induced; D008875:Middle Aged; D011237:Predictive Value of Tests; D011247:Pregnancy; D011446:Prospective Studies