Final answer:
Oligomenorrhea is defined as scanty menstrual flow and refers to infrequent or light menstrual periods. It can be caused by hormonal imbalances, PCOS, stress, excessive exercise, or certain medical conditions.
Step-by-step explanation:
Oligomenorrhea is defined as scanty menstrual flow. It refers to a condition in which a woman experiences infrequent or light menstrual periods. This can be caused by various factors, such as hormonal imbalances, polycystic ovary syndrome (PCOS), stress, excessive exercise, or certain medical conditions.