A nurse is caring for a newborn who is large for gestational age and is 12 hours old.
Which of the following laboratory tests should the nurse monitor based on the client's condition?

Choice A rationale

For a client with moderate abruptio placenta, which involves premature separation of the placenta from the uterine wall, the primary concern is fetal well-being due to impaired oxygen and nutrient exchange, and maternal hemorrhage. Therefore, continuous monitoring of fetal heart rate (FHR) tracings is a priority to assess for signs of fetal compromise (e.g., late decelerations, bradycardia, nonreassuring patterns) and determine the urgency for delivery.

Choice B rationale

Ferning is a microscopic test where a sample of vaginal fluid is allowed to dry on a slide; the characteristic fern pattern indicates the presence of amniotic fluid. This test is used to confirm rupture of membranes. This is not the immediate priority intervention for abruptio placenta, which is focused on managing hemorrhage and fetal distress, and a vaginal examination may be contraindicated if bleeding is severe.

Choice C rationale

Assessing for cervical dilation requires a vaginal examination. While important for determining labor progression, a vaginal examination is often contraindicated in the setting of unexplained vaginal bleeding until a placenta previa is ruled out by ultrasound, as a digital exam could potentially cause a severe hemorrhage if the placenta is covering the cervix. The FHR is a higher priority.

Choice D rationale

Administering oxytocin is a uterotonic agent used to induce or augment labor. In moderate to severe abruptio placenta, if the client is not in active labor or the bleeding is significant, emergency cesarean delivery might be required. Furthermore, the goal is often to deliver the fetus as quickly and safely as possible; oxytocin is not the initial management and could increase uterine tone, potentially worsening the abruption if not used carefully under close monitoring.

Choice A rationale: A fundal height of 36 cm at 42 weeks gestation is concerning because fundal height should approximate gestational age in weeks ±2 cm. At 42 weeks, expected measurement is about 40–44 cm. A measurement of 36 cm suggests possible intrauterine growth restriction (IUGR) or oligohydramnios, both of which are complications associated with post-term pregnancy. This discrepancy requires further evaluation with ultrasound and fetal surveillance to ensure adequate growth and amniotic fluid volume.

Choice B rationale: A cervix that is closed and thick at 42 weeks gestation is not an immediate problem requiring intervention. Cervical ripening varies, and although induction may be considered at this gestational age, the cervix itself being closed is not pathologic. It simply indicates that spontaneous labor has not yet begun. This finding does not require urgent intervention but may guide decisions about induction methods such as prostaglandins or mechanical ripening.

Choice C rationale: A vertex presentation at +1 station is a favorable finding. Vertex is the optimal presentation for vaginal delivery, and +1 station indicates that the fetal head is descending into the pelvis. This is reassuring and does not require intervention. It suggests that the fetus is well-positioned for labor and delivery, and no abnormality is present in this assessment.

Choice D rationale: Clear to white mucus-like vaginal discharge is a normal physiologic finding in pregnancy, known as leukorrhea. It results from increased estrogen and cervical gland activity. This type of discharge is not associated with infection or rupture of membranes. Since it is expected and benign, it does not require intervention. Only abnormal discharges such as foul-smelling, green, or bloody secretions would warrant further evaluation.

Choice E rationale: A fetal heart rate of 150/min is within the normal baseline range of 110 to 160 beats per minute. This indicates adequate fetal oxygenation and no evidence of tachycardia or bradycardia. Since the rate is normal and reassuring, it does not require intervention. Continuous monitoring remains important, but this specific finding is not problematic.

Choice F rationale: A nonstress test that is nonreactive is concerning because it indicates that the fetus did not demonstrate adequate accelerations of heart rate with movement. A reactive NST requires at least two accelerations of 15 beats/min above baseline lasting 15 seconds within 20 minutes. A nonreactive result suggests possible fetal hypoxemia, sleep state, or neurologic compromise. This requires further evaluation with a contraction stress test or repeat biophysical profile.

Choice G rationale: A positive Group B Streptococcus culture is abnormal and requires intervention. GBS colonization increases the risk of neonatal sepsis, pneumonia, and meningitis if transmitted during delivery. Standard care is intrapartum prophylaxis with IV penicillin or ampicillin during labor. Since this client is GBS positive, the nurse must ensure that prophylactic antibiotics are administered at the onset of labor or rupture of membranes to prevent neonatal infection.

Choice H rationale: A biophysical profile score of 8/10 is considered reassuring. The BPP assesses fetal breathing, movement, tone, amniotic fluid volume, and NST. A score of 8 to 10 indicates normal fetal well-being, while 6 is equivocal and ≤4 is abnormal. Since this client’s score is 8, no immediate intervention is required. This is a reassuring finding and does not indicate fetal compromise.