
Written by Jane Sagui, Pollie CEO & co-founder
We know that hormones are important when it comes to pregnancy, but do you know how?
Female reproductive hormones perform a delicate dance from pre-pregnancy through postpartum to conceive, grow, and deliver a healthy baby, as well as readjust your body to a balanced point after birth.
Pregnancy and postpartum both bring a fair share of physical and emotional changes, and pregnancy through gestational surrogacy is no exception. Whether you're in Massachusetts, New York, or elsewhere in the world, being educated about what causes those changes can make the transitions from surrogate pregnancy through postpartum smoother. Today we will be taking a look at what hormonal shifts our bodies undergo from conception through postpartum and explain ways that you can support your body for a more seamless surrogate pregnancy.
What Hormones Are Important for Pregnancy?
A variety of hormones are important for a surrogate. We will be focusing on several of the main players today and explain both their function and how they can cause changes for your body and emotions.
Before we get started, let’s level set with the main hormones:
Human chorionic gonadotropin (hCG): Human chorionic gonadotropin (hCG) is what a pregnancy test detects for a positive result (or, conversely, detects the absence of for a negative result). The placenta produces hCG after implantation, and it is key to the development of the “corpus luteum,” which is a (temporary) structure that develops in your ovaries in early pregnancy. The corpus luteum is responsible for early progesterone and estrogen production. hCG peaks by 11 weeks at the latest.
Estrogen: Estrogen is one of the queen bees of pregnancy, and one of the female hormones you are most likely to have heard of. During your monthly cycle, estrogen behaves in a cyclical pattern, rising until ovulation and then falling after. It creates a slew of feel-good hormones like serotonin and endorphins, and its monthly decrease before your period can contribute to down feelings many women can feel in the week before they menstruate. During pregnancy, estrogen rises constantly until peaking before labor. The corpus luteum initially produces estrogen before being taken over by the placenta. Estrogen is made up of 3 different types:
Estrone (E1): Female bodies produce estrone, or E1, post-menopause. It is a weaker form of estrogen but can be transformed into the other two types if necessary. Which brings us to ...
Estradiol (E2): Estradiol, otherwise known as E2, is the most common type of estrogen in adulthood. Too-high levels of E2, particularly if E2 is high relative to progesterone, can result in symptoms like libido loss, a decrease of bone density (osteoporosis), acne, sore breasts, painful periods, and more.
Estriol (E3): Estriol, or E3, is the most noteworthy estrogen type during pregnancy. It helps the womb develop its lining and rises throughout your entire pregnancy. Levels of estriol peak just before birth, and then drop rapidly. (PS, did you know that you will produce more estrogen during a single pregnancy than you do during the rest of your entire life?)
Progesterone: Progesterone is another well-known hormone that also plays a key role throughout your life. Unlike estrogen, progesterone rises after ovulation before decreasing quickly pre-period if it realizes your body is not pregnant. If it realizes you are indeed pregnant, like estrogen, it will continue to rise for the duration of your pregnancy. The reason for this pattern is that progesterone’s main role is to build up the uterine lining to prepare your womb for a pregnancy: it makes the uterus receptive by inducing it to produce the proper nutrients to support the embryo. In addition to being a key player in building the uterine lining, progesterone also prevents the uterus from contracting and catalyzing preterm labor. This is why progesterone is one of the medications you may be instructed to take in the early days of your surrogacy journey. (You can read more about the hormones you take to become a surrogate and synch your cycle with the egg donor in this related blog post.) It is usually administered vaginally in the form of a vaginal insert or cream. During pregnancy, progesterone is first largely secreted by the corpus luteum (and assisted with medication for a surrogate), before being taken over by the placenta. While estrogen is energizing, progesterone is calming, and dropping progesterone can be a cause of anxiety during PMS and the postpartum phases.
Prolactin: Prolactin is key to breastmilk production in addition to assisting with key fetal development milestones. It is a key driver of sore breasts, vaginal dryness, and other new symptoms postpartum. Prolactin is low for women who are not pregnant, and elevated levels can be a cause of infertility.
Relaxin: Like the name suggests, this hormone also helps to prevent the uterus from contracting, particularly during the early days of pregnancy. In addition to this key role, relaxin helps the surrogate’s body relax for labor.
The Pregnancy Journey: What’s Changing?
Your surrogate pregnancy is such an exciting time, and it's one that is filled with no shortage of shifting hormones!
As hinted above, these hormones play different roles at different times throughout carrying a baby. Understanding these shifts, as well as side effects that you may experience with these fluctuations, is a helpful tool to feeling in control of your body.
1st trimester

1st trimester (weeks 1 - 12) is notorious for morning sickness, fatigue, tender breasts, new cravings, constipation, more frequent urination, headaches, and weight fluctuations.
Not surprisingly, rapidly-fluctuating hormones are at the root of most of these symptoms. Your body is experiencing higher-than-ever estrogen, progesterone, relaxin, and hCG, and these changes do not occur without changes for your body.
Let’s take a quick look at several of these symptoms and the hormone changes behind them:
Morning sickness: Morning sickness is a tricky one, and there is varying evidence behind what truly causes it. That said, it is widely agreed that hCG at least plays a role. Along with catalyzing the development of the corpus luteum, hCG heightens your sense of smell. This can cause aversions to food that previously did not exist, and in many cases, nausea and vomiting.
Constipation: Remember how both progesterone and relaxin help relax your muscles to prevent muscle contractions and early labor? Unfortunately, that is not isolated to your uterus; it impacts your digestive tract as well. A more relaxed digestive system equates to, well, less going number 2.
Fatigue: In the early days of pregnancy, you are hitting record highs of hormones like estrogen and progesterone that relate to your monthly cycle. As progesterone increases feelings of calmness, this can also cause extreme fatigue (along with the physical feat of beginning to grow another human!).
2nd trimester

2nd trimester (weeks 13 - 28) generally sees a cease or decrease to some of the 1st trimester’s most bothersome symptoms like morning sickness due to hCG decreasing. However, this phase introduces its own host of symptoms, including body aches, darkening skin around the nipples and other areas of your body, facial and extremity swelling, and sinus trouble.
Yet again, hormones are the culprit behind these symptoms. In the second trimester, hormones like estrogen, progesterone, and prolactin continue to rise, while hCG experiences a decrease once its hard work developing the corpus luteum is complete.
These changes, like the 1st trimester, can instigate changes:
Skin pigmentation changes: This one, also known as “melasma,” or the “mask of pregnancy,” is largely due to hormones. The changing hormones during the 2nd trimester can encourage more rapid growth of pigment-producing skin cells. Women will find an increase in darker skin patches, particularly following sun exposure. Don’t worry if you find yourself developing melasma, though: it is harmless and will fade postpartum for most women. Many women also experience melasma as a side effect of hormonal contraceptives.
Sinus trouble: If you have been pregnant before, you may have experienced an uptick in nasal congestion and even nosebleeds starting in the second trimester. Believe it or not, the culprit behind this is indeed hormones: as estrogen and progesterone continue to rise through this phase, they have been shown to have an impact on your nose’s mucous membranes.
Increased hair and nail growth: For most women, this one is a symptom that is welcome! At around week 20, many women start to notice accelerated nail growth and a thicker head of hair. This is due to your ever-rising estrogen, which causes hair to be in a constant growing (not shedding) state and encourages nail growth as well. Increased blood flow during pregnancy helps as well. Quick tip: You should keep in mind that these changes are temporary; more on that below.
3rd trimester

In the 3rd trimester (weeks 29 - 40), your body will have reached its peak levels of estrogen, progesterone, and prolactin in preparation for birth. Skyrocketed estrogen and progesterone can lead to positive feelings and good moods. Still, less-than-ideal symptoms persist for many: Mood swings, sore breasts, increased swelling, hemorrhoids, insomnia, heartburn, shortness of breath, and early contractions are all common complaints of this phase.
Below are examples of how hormones are likely contributing to these symptoms:
Water retention: As you know by now, estrogen will have hit its peak in the third trimester. High estrogen brings along swelling, which is why you may find your ankles, hands, and face feeling a bit puffy.
Acid reflux or heartburn: Discomfort post-meals is not just due to your baby growing more and more by the day. Similar to how progesterone can relax your digestive tract in the first trimester and lead to constipation, it can also relax your esophagus. This enables more foods and liquid to, well, travel back up - which is ultimately what leads to heartburn.
Tender, sore breasts: This is likely one you have noticed throughout the course of your pregnancy, but for many women, it hits its peak during the 3rd trimester. This is because our bodies have accelerated prolactin production to prepare for breastfeeding. Your breasts also may begin to leak a bit at this point which is normal.
Postpartum
Once you deliver your surrogate baby, your hormones are all about you; and the postpartum transition is no joke! Unlike your own pregnancies, you are going through postpartum without having to take care of a newborn so you can truly focus on your own wellbeing.
Your estrogen and progesterone levels, which had been steadily rising throughout the entire pregnancy, plummet rapidly after delivery. On the other hand, prolactin will be at its high point.
These extreme changes can cause a variety of physical and emotional changes:
Menopause-like symptoms: Many women also experience menopause-like symptoms after childbirth such as vaginal dryness. This is normal and an effect of our body’s prolactin production, which makes it harder for vaginas to self-lubricate.
Baby blues to postpartum depression: Your estrogen and progesterone levels, which had been steadily rising throughout the pregnancy, plummet rapidly after delivery. This can contribute to anything from the baby blues to full-fledged postpartum depression. While some degree of mood swings and feeling down is normal post-birth, if you feel it is impacting your daily life and surpassing the highs and lows of your normal day-to-day you should seek help from a qualified practitioner.
Hair loss: While increased hair thickness is a hallmark of pregnancy, hair loss is a common effect of postpartum. When you deliver a baby, you lose your placenta, which was responsible for the majority of estrogen production for the majority of your pregnancy. Without this placenta, estrogen levels plummet rapidly and your hair is no longer signaled to remain in a growing phase. What follows is a period of rapid shedding, but don’t worry: Most women’s manes will simply return to the thickness they were pre-pregnancy.
How To Improve Symptoms of Hormonal Fluctuations
For many women, minor lifestyle tweaks can help tremendously in improving pregnancy and postpartum hormone fluctuation symptoms. While hormones undergo radical changes during pregnancy no matter how optimal your lifestyle—and it is likely impossible to avoid any symptoms of pregnancy and postpartum—there are steps you can take to support the rest of your body in efficiently taking you through this journey.
Take the following items:
Nutrition: Nutrition is of course key to healthy fetal development, but it doesn’t stop there. What we eat

is key to balancing hormones. In general, a diet that is anti-inflammatory for you is best, as it will help the rest of your body keep functioning strongly alongside your transitioning hormones. This varies from person to person—some women may find they feel better without eating dairy, while others can tolerate all the yogurt and cheese they want. In general, though, eating more vegetables, high-quality protein sources, and healthy fats is a recipe for happy hormones.
Exercise: Our bodies are made for movement, but not all exercise is equal. Similar to diet type, some people may thrive with cycling or running while someone else does well with yoga and pilates. Although you should be mindful of decreasing workout intensity while pregnant, movement is still helpful for a healthy pregnancy. Once you are cleared to exercise postpartum, you can encourage accelerated hormone balance through stress management and blood sugar regulation. That said, it is important to not over-exercise for your body, as this can lead to chronic stress response and skyrocket cortisol levels.
Stress management: Cortisol is a stress hormone produced by our adrenal glands that instigates our “fight or flight” response. While some cortisol is good, modern-day society has left many of our bodies buzzing with chronically-high cortisol levels, which ultimately taxes our adrenals. Cortisol can also lead to increased androgens and other sex hormone imbalances, thus increasing the risk for transfer and pregnancy complications.
Lifestyle: Makeup products and household cleaners often contain harmful chemicals called endocrine disruptors that can throw off your internal balance and also be harmful to a developing baby. Consider replacing harmful products with clean options; they will be better not just for yourself and the baby you’re carrying, but the environment as well.
Keep in mind that you should work with a qualified medical provider before making any changes to your diet or exercise routine, especially while pregnant.
Real Circle Surrogates: Getting Through the Postpartum Phase
“How do you go from having such an impact on people’s lives and doing something so great and fulfilling and rewarding to just being done?” this was what one of our surrogates, Sarah, found the hardest. “It was a struggle, and I’m sure the postpartum hormones didn’t help! One minute I wanted to cry for no reason at all, and the other, I’m so happy and grateful for my life and the people I have in it, including the parents of the babies I have carried.”
Our surrogates have shared that they are often asked about how they deal with delivering a baby and then leaving the hospital “empty-handed.” But they feel quite the opposite!
“I’m so excited to go home and get a good night’s sleep!” one surrogate shared. “There’s not a newborn keeping you up all night!”
Another surrogate was excited for time with her family. “I could go home and focus on my husband and my children, without having a newborn to care for.”
A surrogacy journey affects you physically and emotionally. Just as you’ll allow yourself to heal physically, you have to allow yourself to recover mentally as well. Take good care of yourself, allow yourself to “feel,” and remember the great gift you just gave to deserving parents.
The Value of a Strong Support System
Our surrogates share who supported them most during their postpartum recovery period:
I have a wonderful OB team who has been with me through the births of both of my sons as well as the loss of a pregnancy, they were so supportive and caring after delivery. There was a beautiful moment right after delivery where all the focus was on the new baby, as all moms know once the baby is out doesn’t mean your job with delivery is over, I was struggling with those last few contractions and my OB Dr looked me in the eye and put his hand on my knee and said ” you did good” it gave me the energy I so desperately needed to finish my job. – Tenley
My IPs have been such amazing support to me. But also in my personal life, two close friends have truly been there in such an amazing way. They became so close too with the IPs while they were here. – Lindsay
My husband has been the best support in my postpartum recovery. The intended fathers were around for four days after delivery and they were also super caring and supportive period together. Those three men helped me more than I can say. Also the team at Circle checked on me and they have been supportive and never left me wondering during this whole journey. – Amanda
My husband was a huge support! He put in extra effort with watching the kids, making dinner, etc. to help me recover. I also loved being in the surrogacy and pumping Facebook groups. Whenever I had questions I always knew those women were there to help. – Heather
My sister Brittany and my son Ronald where my biggest support and help during postpartum recovery. My son, who is 13, will bring me meals, checking in on me, and do whatever it took to make sure I was OK and didn’t need anything. – Ronda
Advice for Women Considering Surrogacy
Here's what two of our surrogates have to say to women who are considering surrogacy or who are currently undergoing their surrogacy journeys:
I never expected what postpartum hormones would mean emotionally. But because of this, I would like future surrogates to know that this process is over a year long. It changes you period. It is so much bigger than just a pregnancy. Essentially, you are the most important person in the intended parents lives and a part of this major event, and then it ends. That is something to prepare for, the end. Even if you stay in contact with your intended parents, the relationship shifts. – Amanda
My advice would be to listen to your body, take your time healing, and don’t compare yourself to others because we’re all different and our bodies are created differently. We heal and recover on our own time. It’s OK to not feel like yourself right away. You will get there. – Ronda
In Conclusion
Being pregnant as a gestational carrier takes your body on a roller coaster of changes, and hormones are no exception. Estrogen, progesterone, hCG, prolactin, and other compounds all play a leading role in helping your body prepare itself for a healthy pregnancy, delivery, and baby. These changes do not come without their side effects, though. It is important to both understand why you may be experiencing certain symptoms, as well as having a game plan for effectively setting your body up for the smoothest, strongest pregnancy possible. And, as always, please contact your doctor with specific questions, issues, or changes during your surrogate pregnancy.
If you're interested in learning more about becoming a surrogate or are feeling ready to apply, please visit our website to learn more about the process and becoming a surrogate!