Final answer:
A negative Contraction Stress Test (CST) is when there are 3 contractions in 10 minutes without fetal heart rate decelerations, indicating fetal well-being.
Step-by-step explanation:
A negative Contraction Stress Test (CST) is characterized by the absence of significant fetal heart rate decelerations during monitored contractions. A normal CST often involves three contractions over a 10-minute period without worrisome decelerations in the fetal heart rate, which is indicative of fetal well-being. Therefore, the correct answer to the question "A negative CST is when there are ___ contractions / ___ mins without fetal heart rate decelerations right" is A) 3 contractions / 10 mins.
Understanding the significance of a negative CST comes from recognizing that during labor, each contraction can reduce oxygen flow to the fetus, necessitating periods of relaxation between contractions. Prolonged or powerful contractions can potentially lead to fetal distress if proper oxygenation is not restored. Monitoring fetal heart rate and contractions help manage the balance needed to avoid complications.