Traditionally, this was also a time to reintroduce the mother to the world. The Chinese believe mothers are in a highly weakened state in the period immediately following birth. Just as English custom calls for new mothers to enjoy a brief period of confinement, Chinese mothers have traditionally been expected to rest indoors for one full month after giving birth. This helped ensure they didn't become overtired, or contract any germs or illnesses from the outside world that could prove dangerous in their weakened state. Besides resting, they drank a nutritious broth made with pig's feet, eggs, vinegar and ginger. Many new mothers still follow this ritual today.
Here you can see my "Poh poh" and my "Grandma" with me on the day of my Red Egg and Ginger Party.