Contraction stress test

The contractions stress test ( Oxytocinbelastungstest, OBT ) is performed in pregnancy. Objective of the test is to produce contractions so as to check the supply of the fetus during labor. The test allows statements about the function of the placenta ( placenta) - for example, whether the fetal supply is sufficient or whether the birth initiated or a caesarean section should be performed.

Reasons to perform a stress test contractions are an eye-catching CTG (irregular or high or low childlike heart rate), suspected placental insufficiency (insufficient supply of the fetus ) or calculated transmission (exceeding the expected birth Termines 8-10 days).

Implementation

The performance of the test is usually done in a maternity clinic with continuous monitoring of the fetal heart rate. It is enhanced with an infusion of oxytocin ( oxytocic ) continuously until a regular uterine contractions is reached. Alternatively, a nasal spray with oxytocin are administered on a regular basis - but here is the dose is less well controlled. If during the test abnormalities in the fetal heart activity occur, further steps must be planned depending on the type of fetal heart response, gestational age, fetal position and condition of the cervix. The choices are monitoring, induction of labor or birth by Caesarean section.

Clinical Significance

Since the contractions stress test has no evidence-based clinical benefit and a false positive rate of up to 50 % has, the test is seen by the German Society of Gynecology and Obstetrics as obsolete.