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An Expert Guide to Pregnancy Hormones

What to expect and how to prepare for growing an entire human.

An Expert Guide to Pregnancy Hormones

Hormones play a starring role in your body—from puberty and periods to pregnancy and menopause. The transition between each of these phases can make it feel like the whole world has gone off its axis, and pregnancy hormones especially come in hard and fast. 

Once your body is set to redecorate your uterus for a new tenant, it’s time to prep for the hormone boost. We’ve put together a quick guide to pregnancy hormones, so your first trimester is a piece of cake (or at least you know why you’re craving one).  

Hormone Changes In Your First Trimester

Pregnancy begins with a rapid increase of estrogen, progesterone, human chorionic gonadotropin (hGC), and thyroid-stimulating hormones (TSH). According to a review of pregnancy changes in the body by the National Review of Medicine, the first burst of estrogen and hCG in the first trimester might cause waves of nausea, or “morning sickness” that some experience. A woman will produce more estrogen during pregnancy than at any other time—so, it’s no wonder everything feels different

Implantation of a fertilized egg tells your body that there’s no need for a period. Estrogen and progesterone hormones signal to start thickening the uterine lining, as well as the growth of the uterus to make space for the fetus. These hormones also start directing blood flow and essential nutrients to your fetus for healthy growth and development. You’ll probably start to feel soreness in your breasts and have to use the bathroom a lot more frequently.

Thyroid hormones and your metabolism will kick into overdrive in order to contribute to fetal brain development. While your baby grows, progesterone actually helps keep your muscles relaxed, so you don’t contract until it’s time to give birth. All of these physiological changes will make you feel much more tired than usual, and emotions will swing up and down—from irritability to anxiousness and back again. Remember this is normal! Your first trimester can also give you that lovely pregnancy glow, and you may notice the strong, growing fingernails of your dreams.


Hormone Changes In Your Second & Third Trimester

Your body will start getting used to this new normal in the second trimester, and your morning sickness should subside. While your baby grows, you’ll notice some water weight gain and discomfort during exercise. With progesterone levels up and your muscles relaxed, consider taking it easy so you don’t injure yourself. 

Checkups with your doctor, especially during your second trimester, are encouraged. Because your body wants to send extra nutrients to the baby as it enters its very first growth spurt, some women can develop gestational diabetes mellitus (GDM). This is caused by a placenta-made hormone (lactogen) preventing effective insulin usage, causing glucose buildup in the bloodstream. This affects 3-8% of pregnant women in the United States. 

The second trimester is likely the most calm of your pregnancy before moving into preparation for labor. Some women report leaking breasts when hormones signal the start of milk production.

Your third trimester is all about getting your baby to the finish line. As your body makes final adjustments (like strengthening your pelvic muscles), estrogen and progesterone hit top levels. If you haven’t experienced leaking breasts yet, the hormone prolactin will most likely start that process. 


It Takes A Village

Pregnancy can be an amazing experience, though every experience can vary significantly. The changes in your hormones can help your body bring a healthy baby into the world, but hormones can also create different levels of discomfort. If you’ve ever needed support from friends, family, and a partner—it’s now. Emotions run high, but the more prepared you are, the better you’ll feel. Support is the most important thing while your insides work overtime, so talk to your doctor about things like breathing exercises and stress-relieving techniques to add to your routine. And if you’re looking for extra support as you try to conceive, try our OBGYN-formulated PREGGO vitamins for the very first step on this journey. 

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