What are the two main physiological changes in the pelvis that occur due to hormone influence during pregnancy?

During pregnancy, the body undergoes significant physiological changes, particularly in the pelvic region, to prepare for labor and delivery. The correct choice highlights increased elasticity and flexibility as two main changes that occur due to hormonal influences, primarily from relaxin and progesterone.

Relaxin is a hormone that increases during pregnancy and plays a crucial role in softening and relaxing the connective tissues in the pelvis. This facilitates the widening of the pelvic joints, allowing for more room during childbirth. Additionally, progesterone contributes to the relaxation of the ligaments and muscles, further enhancing flexibility in the pelvic area. These adaptations are essential for accommodating the growing fetus and preparing for the physical demands of labor.

The other options suggest changes that are contrary to what actually happens during pregnancy. For instance, inhibition of blood flow would be detrimental to both the mother and fetus, while increased rigidity and inflammation would not be conducive to the necessary adaptability of the pelvis for delivery. Decreased hormonal activity contradicts the physiological response in pregnancy, where hormonal levels rise significantly to support these necessary changes. Therefore, the increase in elasticity and flexibility is vital for a successful childbirth experience.