When evaluating a patient for sexually transmitted infections (STIs), the nurse should be aware that the most common bacterial STI is:

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.

Choice A reason: The NST has no known contraindications, as it is a non-invasive and safe test that does not stimulate uterine contractions or cause fetal distress. It is the most widely used method of antepartum fetal surveillance.

Choice B reason: The NST is not slightly more expensive than the CST, as it requires less time and equipment. The NST usually takes 20 to 40 minutes, while the CST may take up to 2 hours. The NST only needs a fetal monitor, while the CST also needs an intravenous line and oxytocin infusion.

Choice C reason: The NST does not have fewer false-positive results than the CST, as it has a higher rate of nonreactive results that may indicate fetal compromise when there is none. A nonreactive NST is one that does not show at least two accelerations of the fetal heart rate of 15 beats per minute or more lasting 15 seconds or more in a 20-minute period.

Choice D reason: The NST is not more sensitive in detecting fetal compromise than the CST, as it has a lower predictive value for fetal well-being. A reactive NST is one that shows at least two accelerations of the fetal heart rate of 15 beats per minute or more lasting 15 seconds or more in a 20-minute period. However, a reactive NST does not rule out the possibility of fetal hypoxia or acidosis.