Pregnancy Hormones: Relaxin

From the moment of conception, pregnancy hormones, such as relaxin, play a vital role in orchestrating the transformations that occur within a pregnant body. In this blog post, we will explore what relaxin is, what it does in the body, and the discomforts it may cause those who are pregnant.

What is the pregnancy hormone relaxin?

Relaxin is a hormone produced primarily by the corpus luteum in the ovary and later by the placenta during pregnancy. The term “relaxin” aptly describes its main function, which is to relax and loosen various tissues and ligaments in the body. It is part of the peptide hormone family and plays a pivotal role in preparing a person’s body for childbirth.

What does relaxin do?

1. Ligament Relaxation: One of the primary functions of relaxin is to prepare the body for childbirth. It softens and loosens the ligaments and connective tissues in the pelvis, making it more flexible. By doing so, relaxin helps to widen the birth canal, facilitating the passage of the baby during labor and delivery.
2. Pelvic Floor Relaxation: Relaxin also affects the muscles and connective tissues of the pelvic floor. This relaxation allows the pelvic muscles to expand and stretch more easily during childbirth, minimizing the risk of tears and trauma during delivery.
3. Softening of the Cervix: Relaxin assists in the softening and ripening of the cervix. As labor approaches, relaxin helps to thin and dilate the cervix, aiding in the process of labor initiation.
4. Joint Mobility: Beyond its impact on the reproductive system, relaxin influences joint mobility throughout the body. It affects not only the pelvic joints but also other joints such as the knees, wrists, and ankles. This increased joint mobility can be beneficial during pregnancy, as it helps the body accommodate the growing fetus.

Discomforts caused by relaxin

While relaxin is a vital hormone in pregnancy, its effects on the body can lead to certain discomforts for those who are pregnant. Some common discomforts associated with relaxin include:

1. Pelvic Pain: The relaxation of ligaments and joints in the pelvis can result in pelvic pain or discomfort, commonly known as pelvic girdle pain. This pain may be felt in the lower back, hips, groin, or pubic area. Pregnant people may experience difficulty walking, climbing stairs, or changing positions due to pelvic pain.
2. Increased Joint Vulnerability: The softening of ligaments and increased joint mobility caused by relaxin can lead to joint instability. Pregnant people may be more prone to sprains, strains, and other joint-related injuries, especially in weight-bearing joints such as the ankles.
3. Foot Changes: Relaxin can also affect the ligaments in the feet, leading to changes in foot structure and increased foot size. Many pregnant people experience foot swelling, arch collapse, and a temporary increase in shoe size during pregnancy.
4. Acid Reflux: Relaxin’s impact on the muscles extends to the gastrointestinal system, causing relaxation of the lower esophageal sphincter. This relaxation can lead to acid reflux or heartburn, a common discomfort experienced by pregnant people.

Pregnancy hormones like relaxin play such a vital role in preparing a person’s body for childbirth. Its ability to relax ligaments, soften tissues, and increase joint mobility is crucial for accommodating the growing fetus and facilitating a smoother delivery. However, these benefits come with their fair share of discomforts, including pelvic pain, joint instability, foot changes, and acid reflux. Understanding the effects of relaxin during pregnancy can help those who are pregnant navigate these discomforts with appropriate care and support.