A client at 34 weeks gestation is scheduled for a nonstress test (NST). What is the primary purpose of this test?

Antenatal corticosteroids, such as betamethasone or dexamethasone, are administered to women at risk of preterm birth to stimulate surfactant synthesis. These steroids induce the maturation of type 2 pneumocytes within the fetal lungs. This pharmacological intervention significantly reduces the incidence of respiratory distress syndrome.

A. Prevent seizures: Magnesium sulfate is the agent of choice for seizure prophylaxis in preeclampsia. Corticosteroids have no anticonvulsant properties and do not alter the cerebral irritability caused by hypertension. They are strictly focused on fetal organ maturation.

B. Increase maternal BP: Corticosteroids can occasionally cause a transient increase in blood pressure or blood glucose, which is an undesired side effect in preeclampsia. The clinical goal is never to raise the arterial pressure further. Careful monitoring of maternal hemodynamics is required post-administration.

C. Enhance fetal lung maturity: The primary indication is to prepare the fetus for potential early delivery necessitated by severe preeclampsia. Steroids decrease the risk of intraventricular hemorrhage and necrotizing enterocolitis in the neonate. They provide a critical survival advantage for preterm infants.

D. Reduce contractions: Corticosteroids do not possess tocolytic properties and cannot halt the labor process. While they are often given alongside tocolytics, their role is purely developmental. They do not interact with myometrial receptors to inhibit uterine activity or contractions.

Ectopic pregnancy occurs when a fertilized ovum implants outside the endometrial cavity, most commonly in the fallopian tube. It presents a high risk for tubal rupture and intra-abdominal hemorrhage. Diagnosis relies on combining quantitative beta-hCG levels with transvaginal ultrasonography findings.

A. Fetal heart beat in uterus: Visualization of an intrauterine pregnancy virtually excludes the possibility of a concurrent ectopic gestation, except in rare heterotopic pregnancies. This finding confirms a normally implanted fetus. It does not provide evidence for an extrauterine implantation site.

B. Elevated BP: Hypertension is not a diagnostic feature of early ectopic pregnancy and is more commonly associated with preeclampsia or chronic vascular disease. While a ruptured ectopic can cause hypotension due to shock, high blood pressure is irrelevant to confirming the location of the pregnancy.

C. Fetal heartbeat outside the uterus: Definitive confirmation is achieved when an extrauterine embryo with detectable cardiac activity is visualized via ultrasound. This finding provides absolute evidence that the pregnancy is located in an abnormal site. It is the most conclusive diagnostic indicator available.

D. Normal hCG: In an ectopic pregnancy, hCG levels often rise more slowly than expected or remain abnormally low for the gestational age. A "normal" or rapidly doubling hCG level is more characteristic of a healthy intrauterine pregnancy. This finding would decrease suspicion of an ectopic.