Labor pain is a major factor in making the placement of an epidural catheter difficult. The epidural, once in place and dosed, eventually decreases the parturient's pain. To achieve this goal as fast and safely as possible it would be helpful to have a parturient who can tolerate and co-operate with the placement of the epidural catheter.

Briefly stopping contractions, the cause of labor pain, could be the key to achieve this goal.

This study will evaluate the safety, efficacy and duration of the drug terbutaline for this purpose.

Inclusion Criteria:

• in labor
• labor pain >3 on visual analog scale (VAS)

Exclusion Criteria:

• cardiovascular disease
• preeclampsia
• diabetes mel-litus
• thyroid disease
• current (outpatient) opioid medication
• recent and / or current use of cocaine
• seizure disorder
• psychiatric disease
• body mass index >35
• preterm labor (<37 weeks pregnant)
• known allergies to any of the three study substances