When Does Relaxin Hormone Start in Pregnancy?

During pregnancy, several reproductive hormone levels peak. One of such hormones is Relaxin – produced by the placenta and ovaries. Its function is to relax and loosen the joints, muscles, and ligaments allowing your body to stretch more flexibly during conception. It prepares you for childbirth by loosening the pelvic ligaments and muscles, making labor easier.

While too much Relaxin can escalate risks of injuries, usually, this pregnancy hormone does not cause any harmful effects. Let us understand more about when does relaxin hormone start in pregnancy, its purpose, role, where it is secreted, possible health conditions it may cause, and other information.

Understanding how hormones like Relaxin work can also help women better recognize the early signs of pregnancy.

Relaxin Hormone During Pregnancy – What is It?

Your reproductive system goes through several changes during pregnancy. The reproductive organs produce hormones to prepare the body for different stages of conception. Relaxin like the name goes, helps relax ligaments, joints, and muscles of the pelvic region. The hormone starts getting produced during a menstrual cycle.

• It assists to ready the uterus for implantation by forming the thick endometrial lining, relaxing the uterus, and majorly to prevent contractions.
• If pregnancy does not happen in a menstrual cycle, this hormone level decreases and surges in the next cycle once again.
• If pregnancy takes place, Relaxin levels keep rising, peaking in the first trimester or up to the initial 12 weeks of pregnancy, before going up and increasing during delivery time.
• During conception, this hormone helps to accommodate the baby by stretching the uterus.

What is the Purpose of Relaxin?

Before a pregnancy occurs, the ovaries already start secreting Relaxin. This pregnancy hormone rises in the later half of the menstrual cycle, preparing the uterine lining for a healthy fertilization and implantation.

• The hormone makes the uterus muscles relax to prevent contractions. Afterward, the placenta, which provides nutrition, oxygen, and food for fetal development – also produces Relaxin.
• The level of Relaxin pregnancy hormone is at the peak when the conception reaches 12 to 14 weeks. This time gives the fetus enough space to grow in the uterus while the hormone helps the body relax and stretch to accommodate the pregnancy tissues and parts.
• It also assists childbirth by relaxing the pelvis and allowing the baby to get to the birth canal.
• It makes the abdominal muscles flexible, preventing preterm labor, and flexing blood vessels to improve circulation during pregnancy.
• Thus, Relaxin plays an important role during labor and delivery, while preparing the cervix (expanding and softening it) for delivery as well.

When and Where Does Relaxin Come in During Pregnancy?

Formation of Relaxin, as understood, begins well before a pregnancy. Ovaries secrete this hormone in the second half of the menstrual cycle. The placenta also produces this hormone. The release of Relaxin may be correlated to hormones such as human chorionic gonadotrophin (HCG) and luteinizing hormone (LH), but the process is complex and involves several other functions.

So, when does Relaxin hormone start in pregnancy exactly?

• This hormone is present in the body at low levels, but the levels rise at the time of ovulation.
• The levels increase during pregnancy and peaks at the end of the first trimester.
• However, Relaxin also begins to reduce in levels after 12 to 14 weeks of conception.
• It rises again before delivery to prepare the body for labor and childbirth, relaxing the pelvis and cervix.

For how long does Relaxin stay in your body after childbirth:

• The Relaxin levels decline after delivery and for several months thereafter.
• It can sometimes take up to a year for this hormone to resume its normal levels originally present during the pre-conception stage.
• The effect of Relaxin may linger even during breastfeeding.
• So, you must stay cautious about health (especially if exercising), due to loosening of joints and ligaments.

Does Relaxin Impact Other Body Parts and Functions?

Here is what to expect out of Relaxin pregnancy hormone:

• Positive Effects: Some studies indicate that this pregnancy hormone can treat tissue hardening that usually leads to scarring. So, Relaxin can treat scarring tissue in lungs or heart, while easing inflammation, and helping recover from injuries. It may also have some significant effect on blood vessels and blood pressure, aiding in growth of new blood vessels.
• Some Side Effects: During pregnancy, this hormone has a relaxing effect, may prevent intestines from tightening, leading to gastrointestinal issues such as bloating, constipation, or indigestion. This pregnancy hormone can influence the pelvic floor, weakening it, resulting in loss of bladder control lightly. As your pelvis and back may become looser due to Relaxin, it may affect your posture a bit negatively.
• Help During Conception: However, in pregnancy, this hormone allows the fetus to grow comfortably in the uterus and emerge successfully during delivery. Taking care at the time of pregnancy and being more cautious can negate any side effect of this hormone.

Health Conditions Because of Relaxin Hormone

Here are the possible risks of health issues due to imbalance in Relaxin levels:

• High Relaxin levels can cause premature labor due to membranes rupturing early. Low levels of this hormone may result in Scleroderma, wherein the skin hardens and thickens abnormally.
• While there is no strict relationship between health issues and Relaxin, women with endometriosis are susceptible to low levels of this hormone.
• Those with high levels of this pregnancy hormone before conception may experience heavy bleeding during menstruation.
• In some cases, Relaxin can lead to pregnancy-related pelvic girdle pain (PGP), causing pain when you change positions in bed, do motor activities, or move around.
• In other scenarios, it may increase pelvic pain slightly in pregnancy in the area between anus and vagina, both sides of lower back, in the inner thighs, or the pubic bone.
• Some people feel weak and unbalanced during pregnancy as Relaxin loosens ligaments and muscles in the abdominal and pelvic area. Doctors can suggest wearing a belly band for support in pregnancy for improved balance and posture in these cases.

Conclusion: Importance of Relaxin in Pregnancy

The above-mentioned information makes it clear that Relaxin is a vital pregnancy hormone. It helps with fetal development, labor, and childbirth. An imbalance in this hormone’s levels may cause some side effects and risk certain health issues. This hormone otherwise supports reproductive and pregnancy wellness overall during conception.

Staying cautious and taking care of health are essential for a smooth journey in pregnancy and delivery, especially with pregnancy hormones causing changes in the body physically and emotionally. You can always seek professional guidance on tackling the side effects of reproductive hormones.