26 yrs old woman comes to the office for a routine visit 6 months after the birth of her first child. Her pregnancy and vaginal delivery were uneventful and her infant is healthy ; she breastfed for the first t months. The patient reports that during the first 2-3 months after childbirth she had exvessive anxiety and worried frequantly about her newborn daughter. She also felt unusually fatigued and irritable, which has worsened over the last several weeks. The pt has also experience constipation, but her appetite is normal and she has gained 2.5kg in the last 3 months. Blood pressure is 130/90mm Hg and pulse is 60/min . Heart and lung sounds are normal. Mild bilateral lower extremity edema is present . Laboratory results are as follows:
Hb 12g/dl , Na 130 mg , K 4.2 mg , creatinine 1.1 mg , glucose 100 mg , total cholesterol 280 mg/dl.
Which of the following is the best nexct step in management?
Cognitive behavioral therapy.
Echocardiogram.
Exercise and dietary modification.
Morning serum vortisol.
Thyroid function studies.