A nurse is caring for a client who is in active labor. The nurse notes early decelerations of the FHR on the fetal monitor tracing. The nurse should identify that which of the following conditions causes early decelerations in the FHR?

Choice A rationale:

The nurse should discontinue the oxytocin infusion if the client's contraction frequency is every 3 minutes. Frequent contractions may lead to uterine hyperstimulation, which can reduce fetal blood flow and oxygenation, potentially causing fetal distress. Normal contraction frequency during labor is typically every 2 to 5 minutes.

Choice B rationale:

Contraction duration of 100 seconds is not an indication to discontinue the oxytocin infusion. The duration of contractions can vary during labor, and 100 seconds is within the normal range of contraction duration, which is usually 45 to 90 seconds.

Choice C rationale:

Fetal heart rate with moderate variability is not an indication to discontinue the oxytocin infusion. Moderate variability in fetal heart rate is a reassuring sign, indicating a healthy fetal response to labor. It shows that the fetus is tolerating the contractions well and is not experiencing fetal distress.

Choice D rationale:

A fetal heart rate of 118/min is not an indication to discontinue the oxytocin infusion. The normal fetal heart rate range is typically between 110 to 160 beats per minute, and a heart rate of 118/min falls within this normal range. However, if the fetal heart rate deviates significantly from the normal range or shows signs of distress, further assessment and intervention are required.

Choice A rationale:

Rh incompatibility occurs when an Rh-negative client is exposed to Rh-positive fetal blood, typically during a prior pregnancy or delivery. The client’s immune system produces anti-Rh antibodies that cross the placenta in subsequent pregnancies, attacking the Rh-positive red blood cells of the fetus. This hemolysis releases bilirubin, leading to hyperbilirubinemia in the newborn.

Choice B rationale:

Rh incompatibility only occurs when the client is Rh-negative and the fetus is Rh-positive. An Rh-positive client will not form antibodies against an Rh-negative fetus, as their immune system recognizes the Rh factor as normal.

Choice C rationale:

This choice is not related to the mechanism of Rh incompatibility. Receiving a transfusion with Rh-negative blood would not cause the mother's immune system to produce anti-Rh antibodies or lead to Rh incompatibility with her newborn.

Choice D rationale:

This choice describes the ABO blood group system, not the Rh factor. ABO incompatibility can occur when a mother with blood type O (producing anti-A and anti-B antibodies) has a newborn with blood type A, B, or AB, leading to hemolysis of the fetal red blood cells. However, the question specifically mentions Rh incompatibility, which involves the Rh factor, not the ABO system.