Introducing First Trimester Hormones

Introducing First Trimester Hormones: Progesterone, Estrogen & hCG

Introducing First Trimester Hormones: Progesterone, Estrogen & hCG

Choosing adoption doesn't change the complexities of pregnancy...

First of all, you’re not imagining it. Your breasts hurt, you’re crying because your tortilla chips are overly salty and you definitely haven’t pooped...or, wait, have you? Nope, you haven’t pooped recently, but you have had to pee constantly for the last three days. Welcome to your first trimester. The good news is that it’s only 12 weeks and, the better news, is that you may be most of the way through it before you’ve realized you’re pregnant. 

Wherever you are in the decision process, whether you’ve already chosen to place your baby for adoption or you’re still reviewing your options, your body is going through something amazing and you’ll want to have the best pregnancy possible. 

First Trimester Hormones

So what exactly is happening? Why do salty snacks make you weepy and when will you start pooping regularly again? When you get pregnant, two hormones that already exist in your body (estrogen & progesterone) start to rise dramatically. These levels peak during your first trimester, then level off for the remainder of your pregnancy. You’ll also start producing a pregnancy exclusive hormone called: human chorionic gonadotropin or hCG. This is the hormone that pregnancy tests detect and react to. And yes, you saw it right, the word “gonadotropin” has the word “gonad” in it, because gonad is the word for the organ (for both males and females) that produces reproductive cells (eggs or sperm). Neat-o.

So which hormone is responsible for which symptom?


Progesterone prepares the body to carry a baby by relaxing the uterus until labor begins. But by letting the reproductive parts of the body relax, it causes some less helpful symptoms such as:

  • Fatigue

  • Mood Swings

  • Constipation

  • Heartburn

Have you yawned excessively while reading this post? We won't take it personally. You are exhausted and you will be. If you can nap, nap whenever and wherever you safely can. Growing a baby is hard work and you’ll be regretting passing up those naps by 30 weeks.

Believe it or not, the mood shifts and irritability associated with pregnancy isn’t due to the rising levels of estrogen. Progesterone is the hormone responsible for moodiness during menstruation, and the increased levels during pregnancy often trigger the abnormal mood swings that will have women rushing off to the drug store for a pregnancy test. 

It’s important to remember that the increase in hormones are not causing feelings of sadness or happiness; they’re amplifying what’s already there. If you’re at all concerned with the extremes of the emotions you may be feeling, check in with your medical provider. They’ll be able to best gauge if you need additional support to get you over the first trimester blues. 

Both constipation and heartburn are also very treatable. You can add fiber to your diet and drink heartburn tea. Many over the counter medications, as well as home remedies, are allowed and encouraged to make you more comfortable. At your confirmation appointment, your medical provider will likely go over a list of medications that have been proven to be safe for both you and baby in each trimester. Before you take something new, just clear it with your provider. Many have a nurse line, or an office email that is monitored by nursing staff. Many insurances also have a nurse help line you could call, and the internet has a lot of reliable sources in a pinch. The bottom line is: you don’t have to suffer needlessly to have a healthy baby. 


Now that we’ve cleared estrogen’s name a little bit, it’s important to know that it’s a very helpful hormone right now. Estrogen helps to regulate progesterone and estrogen increases blood flow in the body. It is generally held responsible for the following:

  • Tender breasts

  • Frequent Urination

  • Congestion

Now’s the time to join the movement and burn that bra! (Actually, don’t do that. Carbon emissions and whatnot). Women experience tender breasts differently but the best remedy if you’re hurting is to change up your bra, take warm baths or showers and wear a supportive sports bra while sleeping. The less they move, the better. Many women find pregnancy pillows helpful at this point. If you sleep on your stomach, try switching it up so you’re not sleeping with pressure on your breasts. Additionally, consider ditching that corset if you’ve been cosplaying or participating in historical reenactment. 

Are you wondering how a baby the size of a raspberry is making you pee constantly? Frequent urination and congestion are caused for the same reason as breast tenderness. Estrogen is pushing your fluids around your body in greater levels. That means your organs are swelling and -- you guessed it -- producing more fluids. More pee, more mucus. The baby is off the hook for this one, using your bladder as a water pillow comes much later in its development.  


We’ll call hCG the catalyst hormone. Without it, your body wouldn’t know it’s pregnant. The role hCG has in your symptoms is less well understood, but many scholars believe that it could be responsible for: 

  • Food Craving

  • Food Aversion

  • Nausea/Morning Sickness

Ask 12 pregnant women how nauseous they were during their pregnancy and you’ll get 12 different answers. Ask those same 12 women what they craved/couldn’t stand and you’ll get 12 different answers that will change 12 times over the 12 weeks of their first trimester. This is the least understood and least predictable symptom of early pregnancy. There is evidence that ties morning sickness to genetics, but it’s not guaranteed that if your mom was sick during her pregnancy that you will be as well. 

There’s no easy treatment for this part of pregnancy. There are lozenges, mints, teas and patches that work for some women but not all. If you’re at all sick, bring it up to your medical provider. For most women, you’ll feel loads better once you’ve crossed into your second semester. However, severe nausea and vomiting could be a sign of hyperemesis gravidarum (HG) and will need to be monitored closely by your provider. 

First Trimester Hormones 

First trimester is very early days in your pregnancy. You may have mixed emotions about being pregnant, but educating yourself on your options and learning about what’s going on in your body will help take some of the unknown out of this time. 

Remember that Adoption Choices of Nevada is here as a resource for you. and keep in mind the following quick tips for your first trimester.

  • Stop smoking, drinking and drug usage

  • Have frequent talks with your medical provider

  • Get support

  • Make yourself as comfortable as you can

  • Rest

  • Continue to do your research

Stay tuned for more information on these!

Adoption and Surrogacy Choices of Reno has been providing adoption and surrogacy services across Nevada since 2012. You can call us to speak to someone now!

Contact Us 24/7: 855-940-4673 (Toll-Free) or 775-825-4673 (Reno)