This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Gynae), Subject name: Gynaecology & Obstetrics
MC cause of anovulation is- 
Select and explain. 
A. PCOS, B. Hyperprolactinemia, C. Premature ovarian failure, D. Low ovarian reserves
A: PCOS
Answer: A: PCOS 
Explanation: Ans. is 'a' i.e., PCOS * Anovulation and ovulatory dysfunction can be caused by a number of factors. The most common cause of ovulatory dysfunction is polycystic ovarian syndrome, or PCOS. Other potential causes of irregular or absent ovulation:# Obesity# Underweight# Extreme exercise# Hyperprolactinemia# Premature ovarian failure# Perimenopause, or low ovarian reserves# Thyroid dysfunction# Extremely high levels of stress