What are the maternal and neonatal risks associated with gestational diabetes mellitus?

Choice A reason: Amniocentesis for fetal lung maturity is not an expected diagnostic procedure for a pregnant woman with bright red, painless vaginal bleeding. It is a procedure that involves inserting a needle into the amniotic sac to obtain a sample of amniotic fluid, which can be used to assess the fetal lung development. It is usually done in late pregnancy or preterm labor, not in the second trimester.

Choice B reason: Contraction stress test (CST) is not an expected diagnostic procedure for a pregnant woman with bright red, painless vaginal bleeding. It is a test that involves stimulating uterine contractions, either by nipple stimulation or oxytocin infusion, to evaluate the fetal heart rate response. It is used to assess fetal well-being and placental function, not to diagnose the cause of bleeding.

Choice C reason: Internal fetal monitoring is not an expected diagnostic procedure for a pregnant woman with bright red, painless vaginal bleeding. It is a method of measuring the fetal heart rate and uterine contractions using electrodes or catheters that are inserted through the cervix and attached to the fetal scalp or the amniotic sac. It is usually done during labor, not in the second trimester.

Choice D reason: Ultrasound for placental location is an expected diagnostic procedure for a pregnant woman with bright red, painless vaginal bleeding. It is a test that uses sound waves to create an image of the uterus, the placenta, and the fetus. It can help to determine the position and attachment of the placenta, which can be the cause of bleeding if it is low-lying or covering the cervix (placenta previa).

Choice E reason: None of the above is not a correct answer. There is one expected diagnostic procedure for a pregnant woman with bright red, painless vaginal bleeding, which is ultrasound for placental location.

Choice A reason: Low birth weight is not a common complication of GDM, as the fetus tends to grow larger than normal due to the excess glucose and insulin in the blood. Low birth weight is more likely to occur in infants of mothers with preexisting diabetes or other conditions that affect placental function.

Choice B reason: Preterm birth is a possible complication of GDM, as the increased fetal size and the risk of maternal hypertension or infection may induce labor before term. However, it is not the greatest risk for the fetus, as preterm infants can survive with proper care and treatment.

Choice C reason: Macrosomia is the greatest risk for the fetus of a mother with GDM, as it is defined as a birth weight of more than 4000 g or 8 lb 13 oz. Macrosomia can cause difficulties during labor and delivery, such as shoulder dystocia, birth trauma, or cesarean birth. It can also increase the risk of neonatal hypoglycemia, jaundice, or respiratory distress.

Choice D reason: Congenital anomalies of the central nervous system are not a common complication of GDM, as they usually occur in the first trimester of pregnancy, before GDM is diagnosed or develops. Congenital anomalies are more likely to occur in infants of mothers with preexisting diabetes or other genetic or environmental factors.