If we cannot sleep, it means that cortisol production is occurring at night, indicating that something is making it necessary for us to remain alert even then. This nighttime cortisol production is caused by an active conflict state, during which our body (even at night) mobilizes its reserves and focuses our attention on resolving the problematic situation.
If menopause were solely about the breakdown of organs critical for species survival, with no biological advantage to the approximately 40 years following it, we likely wouldn’t live this long. Instead, life could end with the “exhaustion” of the ovaries. Most animals, in fact, lose their lives when their fertility ceases.
It's a natural process in the female body that, starting from ovulation, with the increase in progesterone levels, the breast's glandular tissue begins to grow, the cells of the gland lobules start to divide so that by the time the baby is born (in case of fertilization), they are prepared to feed the offspring.
Thus, it's a well-known fact that in case of demand (pregnancy), the mammary gland tissues begin to proliferate so that the "milk factory" can meet the expectations by the due date - because the amount of milk produced depends on the number of mammary glands.