👉 Puerperium, also known as the "first trimester," refers to a period of time during which women undergo menstruation. This is typically from 28 days after conception until about 36 weeks post-partum (approximately 9 months). During this time, the uterus grows and becomes more active, allowing for the release of breast milk. Puerperium is crucial for both motherhood and pregnancy, as it helps to prevent infections and complications during childbirth.