This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Infeility (Eggs'plantation!), Subject name: Gynaecology & Obstetrics
Marker of low ovarian reserve in a premenopausal female: 
Select and explain. 
A. Small antral follicle size, B. Raised LH/FSH ratio, C. Decreased inhibin A, D. Low Anti - mullerian hormone levels
D: Low Anti - mullerian hormone levels
Answer: D: Low Anti - mullerian hormone levels 
Explanation: Markers for low ovarian reserve AMH: Best marker for the ovarian reserve is the AMH. Released from small antral and pre- antral follicles <0.5 ng = Poor reserve 1ng = Borderline reserve >= 3.3 ng = high reserve , risk factor for OHSS in stimulated cycles high day 2 FSH (most commonly performed test) low inhibin B low antral follicle count: total number of antral follicles in both ovaries