Final answer:
The female pelvis is adapted for childbirth with a larger subpubic angle, rounder pelvic brim, and wider lesser pelvic cavity. After giving birth, there may be changes associated with childbirth such as stretching of soft tissues, but these do not alter the pelvic bones themselves. Proper examination post-birth is vital to ensure the health and recovery of the mother.
Step-by-step explanation:
The female pelvis has evolved to accommodate childbirth, and after giving birth, certain changes might become evident. One significant change is referred to as the subpubic angle, which is larger in women and becomes even more evident after childbirth. The female pelvis typically features a broader, rounder pelvic brim and a wider, more shallow lesser pelvic cavity than the male pelvis. This increased pelvic width is due to the broader distance between the ischial tuberosities, which also increases the size of the pelvic outlet. After a vaginal birth the mother may experience stretching of the vaginal canal, cervix and perineum, with the possibility of either an episiotomy or natural tears that require suturing. These changes are not visible on the bony structure of the pelvis but are associated with the birthing process.
Furthermore the involvement of the placenta after childbirth is also crucial. An obstetrician must check that the expelled placenta and fetal membranes are intact to prevent complications such as postpartum hemorrhage. It is also noteworthy that the sacrum in females is wider, shorter, and less curved than in males, which gives the pelvic inlet a more rounded shape beneficial for childbirth. Overall, the female pelvis's adaptations for childbirth become more pronounced after delivering a baby.