Statement I : During pregnancy all events of the menstrual cycle stop and there is no menstruation .

Statement II : In the absence of fertilisation, the corpus luteum degenerates.

Both statement I and statement II are correct .

The correct answer is Option (3) – Both statement I and statement II are correct .

The corpus luteum secretes large amounts of progesterone which is essential for maintenance of the endometrium. Such an endometrium is necessary for implantation of the fertilised ovum and other events of pregnancy. During pregnancy all events of the menstrual cycle stop and there is no menstruation. In the absence of fertilisation, the corpus luteum degenerates. This causes disintegration of the endometrium leading to menstruation, marking a new cycle. In human beings, menstrual cycles ceases around 50 years of age; that is termed as menopause. Cyclic menstruation is an indicator of normal reproductive phase and extends between menarche and menopause.