Oxytocin Challenge Test

Oxytocin Challenge Test (OCT) is done in the hospital to help determine how well the baby will undergo the stress of labor. The OCT is also known as the Contraction Stress Test.

Oxytocin is a medication that causes uterine contractions. While reclining on a 45-degree angle, the woman is given oxytocin intravenously until she has contractions 3 to 4 minutes apart for a full half-hour. At the same time, the heart rate is electronically monitored to check the effect of the contractions on the baby. If the results are positive—that is, the fetal heart rate appears normal during the stress of the contractions—the doctor may recommend a wean birth, since the baby may not be able to tolerate the stress of labor. If the results are negative—that is, the heart rate remains normal during the contractions—the baby will most likely do well during labor.

When taking the OCT, avoid lying flat on your back. This can cause your blood pressure to drop, decreasing oxygen to the baby and possibly causing the appearance of fetal distress on the monitor.