Final answer:
Light spotting before a period can be due to hormonal fluctuations, ovulation, implantation in sexually active women, or conditions such as PCOS. Hormone levels decline as the corpus luteum degrades if there is no pregnancy, leading to endometrial shedding which could manifest as light spotting.
Step-by-step explanation:
Light spotting before a period could be caused by several factors. One explanation could be a hormonal fluctuation, which can cause the endometrium to shed slightly before the actual period begins. Another possibility is ovulation spotting, which can occur approximately two weeks before the period as a result of the egg being released from the ovary. In sexually active women, this could also be implantation bleeding, which happens when a fertilized egg attaches to the lining of the uterus, typically occurring around the time a person would expect their period.
For some women, hormonal conditions such as polycystic ovary syndrome (PCOS) could also contribute to irregular bleeding and spotting. As the body transitions into menopause—during the peri-menopause stage—changes in hormone levels lead to irregular cycles and sometimes to spotting. These hormonal fluctuations cause a decline in progesterone levels, which could also result in irregular spotting or light bleeding.
If no pregnancy occurs during the menstrual cycle, the corpus luteum will eventually degrade and hormone levels will fall, leading to the shedding of the endometrial lining, also known as the menstrual cycle. Spotting before the expected menstrual period could be an early sign of the endometrium beginning to shed.