This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gestational Diabetes Mellitus, Subject name: Gynaecology & Obstetrics
Which amongst the following statements is true? 
Select and explain. 
A. Glyburide is absolutely contraindicated for GDM, B. Patients with GDM/DM should be delivered between 34 and 36 weeks of gestation, as there is a risk of sudden IUFD at full term., C. PTH crosses placenta, D. Phosphatidyl glycerol in amniotic fluid is 100% confirmatory of lung maturity
D: Phosphatidyl glycerol in amniotic fluid is 100% confirmatory of lung maturity
Answer: D: Phosphatidyl glycerol in amniotic fluid is 100% confirmatory of lung maturity 
Explanation: Unlike other oral hypoglycemic agents, glyburide and metformin both are being increasingly used for GDM (not for ove DM) and are found to be safe. Patients with GDM/DM should be delivered between 38 and 39 weeks of gestation, as there is a risk of sudden IUFD at full term. Hormones which do not cross the placenta are 1. Insulin, 2. PTH, and 3. Calcitonin. Lung maturity is delayed in DM/GDM. - L/S >2:1 is not reliable. - Phosphatidyl glycerol in amniotic fluid is 100% confirmatory of lung maturity in these cases.