Hyperpigmentation of the pregnant patient’s face - The hormone relaxin, which is secreted first by the corpus luteum and later by the placenta

- Hyperpigmentation of the pregnant patient’s face, formerly called chloasma and now referred to as melasma, fades after delivery.

- The hormone relaxin, which is secreted first by the corpus luteum and later by the placenta, relaxes the connective tissue and cartilage of the symphysis pubis and the sacroiliac joint to facilitate passage of the fetus during delivery.