An emergency shoulder dystocia delivery occurred that requires the nurse to apply suprapubic pressure. What is the rationale for this action?

A. Fetal heart rate of 118 beats/min. A fetal heart rate of 118 bpm is within the normal range of 110-160 bpm and does not necessarily indicate fetal distress. While continuous monitoring is important in post-term pregnancies, this finding alone does not require urgent assessment.

B. One fetal movement noted in a two-hour assessment by the mother. Decreased fetal movement is a concerning sign that requires further assessment. At 42 weeks gestation, the aging placenta may lead to reduced oxygen and nutrient supply, increasing the risk of fetal compromise. Normally, at least 10 movements should be felt within two hours. A significant decrease in movement could indicate fetal distress or hypoxia, requiring immediate evaluation with a non-stress test (NST) or biophysical profile (BPP).

C. Cervix dilated 2 cm and 50% effaced. A partially dilated and effaced cervix is expected in a post-term pregnancy and does not indicate fetal distress. It suggests that labor may be approaching but does not require additional urgent assessment.

D. Score of 8 on the biophysical profile. A biophysical profile (BPP) score of 8 out of 10 is reassuring and indicates normal fetal well-being. If the score were 4 or lower, it would require immediate intervention, but a score of 8 suggests adequate oxygenation and fetal health.

A. Consuming more calories covers the insulin secreted by the fetus. The fetus does not secrete insulin to regulate maternal glucose levels. Instead, the maternal pancreas produces insulin in response to blood sugar levels, but in diabetes, maternal insulin resistance leads to excess glucose being transferred to the fetus.

B. Fetal weight gain increases as a result of the common response of maternal overeating. While some women with diabetes may have increased caloric intake, this is not the primary reason for fetal macrosomia (large birth weight). The major factor is maternal hyperglycemia leading to excess fetal insulin production and fat deposition.

C. Extra circulating glucose causes the fetus to acquire fatty deposits. In diabetic pregnancies, excess maternal glucose crosses the placenta, leading to fetal hyperinsulinemia. The increased insulin promotes fat storage and excessive fetal growth, leading to macrosomia, which increases the risk of birth complications such as shoulder dystocia.

D. Taking exogenous insulin stimulates fetal growth. Insulin does not cross the placenta, so maternal insulin therapy does not directly affect fetal growth. Instead, fetal macrosomia results from prolonged exposure to maternal hyperglycemia, which causes the fetus to produce excessive insulin and store extra fat.