Prosepective,Randomized, controlled study enrolling full termed parturients admitted for vaginal delivery.~At the sencond stage of labor: 3cm of cervix dilatation, patients will be randomized in 2 groups:~ESP group: patients will receive ultrasound guided, bilateral ESP Block performed at the level of the 3 rd Lumbar transverse process.~Epidural Analgesia Group: Patients will have a classic lumbar continuous epidural analgesia.~For the first group: 20 ml of 0,375% isobaric Bupivacain solution will be injected bilaterally under ultrasound direct vision.~Concerning the second group, patients will have a continuous injection of 0,125% Bupivacain solution associated to 0,25 mcg of Sufentanil/ml through an epidural catheter in the L3-L4 or L4-L5 intervertebral space.~For the 2 groups, analgesia will be assessed during all the labor period hourly using the Visual Analog pain Score (VAS).
Prosepective,Randomized, controlled study enrolling full termed parturients admitted for vaginal delivery.~At the sencond stage of labor: 3cm of cervix dilatation, patients will be randomized in 2 groups:~ESP group: patients will receive ultrasound guided, bilateral ESP Block performed at the level of the 3 rd Lumbar transverse process.~Epidural Analgesia Group: Patients will have a classic lumbar continuous epidural analgesia.