A nurse is reviewing the results of a biophysical profile for a client who is at 37 weeks of gestation.
Which of the following findings indicates fetal well-being?

Choice A rationale

Fundal height measurement is a simple clinical tool used to estimate gestational age and monitor fetal growth. The correct technique involves using a non-stretchable measuring tape to measure the distance in centimeters from the upper border of the symphysis pubis (a fixed bony landmark) to the highest point of the uterine fundus.

Choice B rationale

A full bladder can artificially elevate the uterine fundus, leading to an overestimation of the fundal height and an inaccurate assessment of fetal growth and gestational age. The nurse should instruct the client to empty their bladder before the measurement is taken to ensure the most reliable result.

Choice C rationale

The fundal height measurement is taken vertically, along the midline of the client's abdomen, from the symphysis pubis to the fundus. Measuring horizontally would not provide a clinically relevant or reproducible measure for assessing fetal growth or comparing against expected gestational age measurements.

Choice D rationale

Fundal height measurement should be performed with the client in the supine position with the knees slightly flexed. Placing the client in the left-lateral position is done to prevent supine hypotension syndrome (aorta-caval compression) but would make a standardized and accurate fundal height measurement impossible to obtain.

Choice A rationale: Calcium gluconate must be readily available whenever magnesium sulfate is administered because it serves as the antidote for magnesium toxicity. Magnesium sulfate depresses neuromuscular transmission and the central nervous system, which can lead to respiratory depression, hypotension, and cardiac arrest if serum levels become excessive. Having calcium gluconate on hand allows for immediate reversal of these life-threatening effects. This is a critical safety measure and therefore a required nursing action.

Choice B rationale: Respiratory status must be assessed at least every hour during magnesium sulfate therapy because respiratory depression is a primary sign of magnesium toxicity. Normal adult respiratory rate is 12 to 20 breaths per minute, and a rate below 12/min is concerning. Magnesium depresses the respiratory center in the medulla, and early recognition of hypoventilation is essential to prevent hypoxia and arrest. Thus, frequent respiratory monitoring is a priority nursing action.

Choice C rationale: Monitoring intake and output is essential because magnesium sulfate is excreted almost entirely by the kidneys. Oliguria, defined as urine output less than 30 mL/hr, increases the risk of magnesium accumulation and toxicity. Careful fluid balance assessment ensures adequate renal clearance and helps prevent complications such as pulmonary edema. Therefore, strict I&O monitoring is a critical nursing responsibility during magnesium sulfate therapy to ensure safe drug metabolism and excretion.

Choice D rationale: Intermittent fetal monitoring is not appropriate in this context. Magnesium sulfate administration and preterm labor with rupture of membranes require continuous fetal monitoring to detect early signs of distress. Intermittent monitoring risks missing decelerations or prolonged bradycardia. Continuous monitoring provides real-time assessment of fetal well-being and is the standard of care in high-risk obstetric situations. Therefore, intermittent monitoring is not a correct action and should not be selected.

Choice E rationale: Supine positioning is contraindicated in pregnancy, especially in the third trimester, because the gravid uterus compresses the inferior vena cava, leading to supine hypotensive syndrome. This decreases venous return, cardiac output, and uteroplacental perfusion, compromising both maternal and fetal oxygenation. The correct position is left lateral recumbent to optimize circulation. Therefore, placing the client supine is unsafe and not an appropriate nursing action in this scenario.