How does the relaxin hormone affect a pregnant woman's body?

The relaxin hormone plays a significant role in preparing a pregnant woman's body for childbirth. Its primary function is to increase joint laxity, which is the looseness of the joints. This is crucial during pregnancy as it allows the pelvis to become more flexible for the birthing process. As relaxin is released, it affects the connective tissues and ligaments, resulting in increased flexibility and a greater range of motion in the joints.

While this increased joint laxity is beneficial for accommodating the growing baby and eventually facilitating childbirth, it can also lead to decreased stability in the joints. This is important for fitness professionals to understand, as pregnant women may require specific modifications in their exercise programs to ensure safety and stability during workouts.

In contrast, the other options do not accurately reflect the role of relaxin. The hormone does not promote muscle strength, decrease appetite, or enhance cardiovascular performance. Instead, its main impact is on the musculoskeletal system, particularly in making the joints more adaptable to the changes brought on by pregnancy.