Which pregnant woman should restrict her weight gain during pregnancy?

Choice A reason: This is not the correct answer, as the pregnant woman does not use glucose at a more rapid rate than the nonpregnant woman. In fact, the pregnant woman has lower fasting glucose levels and higher postprandial glucose levels than the nonpregnant woman. This is because the pregnant woman adapts to the increased fetal demand for glucose by increasing her insulin secretion and decreasing her hepatic glucose production.

Choice B reason: This is the correct answer, as placental hormones are antagonistic to insulin, thus resulting in insulin resistance. Insulin resistance is a condition where the cells do not respond well to insulin and require more insulin to maintain normal glucose levels. Placental hormones, such as human placental lactogen, progesterone, and cortisol, increase the insulin resistance of the maternal tissues, especially in the second and third trimesters of pregnancy. This is to ensure that the fetus has enough glucose supply, as the placenta is not insulin resistant and can transport glucose to the fetus².

Choice C reason: This is not the correct answer, as pancreatic function in the islets of Langerhans is not affected by pregnancy. The islets of Langerhans are clusters of cells in the pancreas that produce hormones, such as insulin and glucagon, that regulate glucose metabolism. Pregnancy does not impair the function of the islets of Langerhans, but rather stimulates them to increase their size and number. This is to compensate for the increased insulin resistance and glucose demand of the pregnancy.

Choice D reason: This is not the correct answer, as the pregnant woman does not increase her dietary intake significantly. The pregnant woman needs to consume adequate calories and nutrients to support the fetal growth and development, but not excessively. The recommended weight gain during pregnancy depends on the pre-pregnancy BMI of the woman, but generally ranges from 11 to 16 kg. The recommended calorie intake during pregnancy is about 300 kcal more than the pre-pregnancy intake, which is equivalent to one extra snack per day.

Choice A reason: Maternal placenta previa is not a common complication of gestational diabetes mellitus. Placenta previa is a condition in which the placenta covers the cervix, which can cause bleeding and preterm labor. The risk factors for placenta previa include previous cesarean delivery, multiple pregnancy, advanced maternal age, and smoking.

Choice B reason: Maternal hyperemesis and neonatal low birth weight are not directly related to gestational diabetes mellitus. Hyperemesis is a severe form of nausea and vomiting during pregnancy that can cause dehydration and weight loss. The causes of hyperemesis are not well understood, but it may be influenced by hormonal changes, genetic factors, and psychological factors². Neonatal low birth weight is defined as a birth weight of less than 2,500 grams, which can be caused by many factors, such as prematurity, intrauterine growth restriction, maternal infection, and maternal malnutrition.

Choice C reason: Maternal premature rupture of membranes and neonatal sepsis are not specific to gestational diabetes mellitus. Premature rupture of membranes is a condition in which the amniotic sac breaks before labor begins, which can increase the risk of infection and preterm delivery. The causes of premature rupture of membranes are not clear, but some possible factors include infection, inflammation, stress, and trauma. Neonatal sepsis is a life-threatening infection in newborns, which can be caused by bacteria, viruses, or fungi. The risk factors for neonatal sepsis include prematurity, low birth weight, maternal infection, and invasive procedures⁵.

Choice D reason: Maternal preeclampsia and fetal macrosomia are the most common and serious complications of gestational diabetes mellitus. Preeclampsia is a condition characterized by high blood pressure and protein in the urine, which can lead to organ damage, seizures, and death. The exact cause of preeclampsia is unknown, but it may be related to abnormal placental development, immune system dysfunction, and genetic factors⁶. Fetal macrosomia is a condition in which the baby is larger than normal, usually weighing more than 4,000 grams at birth. This can cause difficulties during labor and delivery, such as shoulder dystocia, birth trauma, and cesarean section. The main cause of fetal macrosomia is excessive maternal glucose, which stimulates fetal insulin production and growth.