Whether you are experiencing pregnancy yourself, supporting a surrogate, deciding to become a surrogate, or living with someone who is pregnant, it’s easy to see how hormonal changes affect daily life. From morning sickness and mood swings to the dramatic physical shifts needed to support a growing baby, the effects of these fluctuations are hard to miss. But what exactly is happening beneath the surface?
Let’s take a closer look at the key hormonal changes that occur throughout pregnancy and explore why they are so essential to the process.
The Body’s Hormonal Transformation
Pregnancy is a time of extraordinary hormonal and physiological adjustments. One of the earliest significant changes involves human chorionic gonadotropin, or hCG. This hormone is unique to pregnancy and is produced almost entirely by the placenta. Rising rapidly during the first trimester, hCG is the hormone detected in pregnancy tests, making it an early indicator of conception.
The primary role of hCG is to stimulate the ovaries to produce increased levels of estrogen and progesterone. These two hormones are critical for maintaining the pregnancy in its early stages. As the placenta matures and begins producing estrogen and progesterone on its own, hCG levels naturally decline.
Estrogen: Supporting Growth and Development
Estrogen levels rise steadily throughout pregnancy and reach their highest point in the third trimester. This hormone has multiple responsibilities, including supporting the development of female sexual traits and encouraging vascularization, or the formation of new blood vessels.
Estrogen is also vital for preparing the body for breastfeeding. It promotes the development of milk ducts, which leads to noticeable breast enlargement during the second trimester as the body readies itself for post-birth nourishment.
Progesterone: Preparing the Body for Change
Alongside estrogen, progesterone levels also surge during pregnancy. This hormone helps the body accommodate the growing baby by softening ligaments and joints. This flexibility allows the organs to shift and make room as the uterus expands from the size of a pear to accommodate a full-term baby.
Progesterone also supports the growth of the uterus itself, ensuring it can safely carry the baby to term.
The Postpartum Shift
After delivery, levels of estrogen and progesterone drop sharply as the body transitions back to its pre-pregnancy state. This sudden hormonal shift can create emotional challenges, often referred to as the “baby blues.” Many women experience mood changes, fatigue, and heightened emotions during this time.
To help manage these changes, it’s important for new mothers and surrogates to seek emotional support, prioritize rest, and engage in gentle exercise. These steps can help regulate stress hormones and increase endorphins, promoting both physical and emotional recovery.
A Complex but Beautiful Process
The hormonal journey of pregnancy is complex, yet every fluctuation plays a role in nurturing new life. Understanding these changes can help expectant parents, surrogates, and their loved ones appreciate the incredible work the body does during this time—and remind them that support and care are just as important as biology.
