The hormone responsible for maturation of mammary gland tissue is:

Choice A reason: Raising the woman's legs is not the best initial response, as it may worsen the dizziness and light-headedness. This is because raising the legs can increase the blood flow to the lower extremities and decrease the blood flow to the brain, which can cause hypotension (low blood pressure) and hypoxia (low oxygen) in the woman and the fetus.

Choice B reason: Having the woman breathe into a paper bag is not the best initial response, as it may not address the underlying cause of the dizziness and light-headedness. This technique is usually used for hyperventilation (rapid breathing), which can cause respiratory alkalosis (high blood pH) and reduce the carbon dioxide levels in the blood. However, the woman may not be hyperventilating, but rather experiencing supine hypotensive syndrome (low blood pressure when lying on the back) due to the pressure of the uterus on the inferior vena cava (a large vein that returns blood to the heart)².

Choice C reason: Turning the woman on her side is the best initial response, as it can relieve the dizziness and light-headedness by improving the blood flow to the brain and the fetus. This is because turning the woman on her side can reduce the pressure of the uterus on the inferior vena cava and increase the cardiac output (the amount of blood pumped by the heart) and the blood pressure. The left lateral position is preferred, as it can also optimize the placental perfusion (the blood flow to the placenta) and the fetal oxygenation.

Choice D reason: Assessing the woman's blood pressure and pulse is an important response, but not the first one. After turning the woman on her side, the nurse should monitor the vital signs and the fetal heart rate to evaluate the condition of the woman and the fetus. The nurse should also check for other signs and symptoms of supine hypotensive syndrome, such as nausea, sweating, and visual disturbances.

Choice A reason: Genetic changes and anomalies are not the most dangerous effect, as they are rare and not directly caused by smoking. Smoking can increase the risk of some birth defects, such as cleft lip and cleft palate, but these are not genetic changes and can be corrected by surgery. Smoking can also cause chromosomal abnormalities in the eggs, but these usually result in miscarriage or stillbirth, not live births.

Choice B reason:Maternal smoking is a significant risk factor for intrauterine growth restriction (IUGR). Nicotine and carbon monoxide from cigarettes reduce oxygen supply to the fetus, leading to lower birth weights and smaller body lengths.

Choice C reason: Fetal addiction to the substance inhaled is not the most dangerous effect, as it is not permanent and can be treated by medication and supportive care. Smoking can expose the fetus to nicotine, carbon monoxide, and other harmful chemicals, which can cross the placenta and affect the fetal brain and nervous system. Smoking can also cause withdrawal symptoms in the newborn, such as irritability, tremors, and difficulty feeding.

Choice D reason:Although prenatal exposure to smoking can affect neurodevelopment and is associated with behavioral issues, extensive central nervous system damage is not the most immediate or dangerous effect. The most critical concern remains intrauterine growth restriction.