What is the result of a nonstress test (NST) in which two or more fetal heart rate (FHR) accelerations of 15 beats/min or more occur with fetal movement in a 20-minute period?

Choice A reason: Nonreactive is not the correct result, as it indicates that the FHR does not show adequate accelerations with fetal movement. A nonreactive NST means that the FHR does not increase by at least 15 beats/min for at least 15 seconds in a 20-minute period. A nonreactive NST may suggest fetal hypoxia (low oxygen) or fetal sleep.

Choice B reason: Reactive is the correct result, as it indicates that the FHR shows adequate accelerations with fetal movement. A reactive NST means that the FHR increases by at least 15 beats/min for at least 15 seconds twice or more in a 20-minute period. A reactive NST is reassuring and suggests that the fetus is well-oxygenated and healthy.

Choice C reason: Positive is not the correct result, as it is not used to describe the NST. Positive is a term used for the contraction stress test (CST), which is a different test that measures the FHR in response to uterine contractions. A positive CST means that the FHR shows late decelerations (decreases in the FHR that begin after the peak of a contraction and return to the baseline after the contraction ends) with at least 50% of the contractions. A positive CST indicates uteroplacental insufficiency (a condition where the placenta does not deliver enough oxygen and nutrients to the fetus) and fetal distress.

Choice D reason: Negative is not the correct result, as it is also not used to describe the NST. Negative is another term used for the CST, which is a different test that measures the FHR in response to uterine contractions. A negative CST means that the FHR does not show any late decelerations during at least three contractions in a 10-minute period. A negative CST is reassuring and suggests that the fetus is well-oxygenated and can tolerate labor.

Choice A reason: A miscarriage is defined as a spontaneous abortion of a fetus before the 20th week of gestation. It is a natural pregnancy loss that occurs before labor begins and is usually caused by chromosomal abnormalities, infections, or maternal health problems.

Choice B reason: A miscarriage is not often attributed to careless maternal behavior such as poor nutrition or excessive exercise. These factors may affect the quality of life of the mother and the fetus, but they are not the main causes of miscarriage. Most miscarriages are not preventable and are not the fault of the mother.

Choice C reason: A miscarriage that occurs before the 12th week of pregnancy may manifest only as moderate discomfort and blood loss, but this is not always the case. Some women may experience severe cramping, bleeding, and tissue passing from the vagina. Others may have no symptoms at all and only discover the miscarriage during a routine ultrasound.

Choice D reason: A miscarriage occurs in more than 5% of all clinically recognized pregnancies. The actual rate of miscarriage is estimated to be 10% to 20%, but many women may not realize they are pregnant or may not report the loss to their health care provider.