- May 19, 2020
- Michael Allibone
- Posted in Resources
Pregnancy hormones give you that healthy glow, stimulate fetal development, and trigger your body's responses to physical activity.
You're likely familiar with some of these hormones – like hCG (remember the fateful pink lines on your pregnancy test?). But what other hormones impact your body during pregnancy? And what do they mean?
From estrogen and progesterone to relaxin and oxytocin, we'll fill you in on the six pregnancy hormones that you need to know about. We'll also look at how prenatal screening tests analyze hormones and what they reveal about your pregnancy.
Estrogen is one of the two main pregnancy hormones. When it comes to estrogen, your body isn’t playing around — you’ll produce more while you’re pregnant than you will throughout the rest of your life.
Estrogen refers to a group of hormones produced in the ovaries. During pregnancy, the placenta also produces estrogen, raising hormone levels. Increased estrogen allows the uterus and placenta to create new blood vessels and transfer nutrients to your baby.
You may experience nausea during your first trimester because estrogen levels increase most rapidly during this time. In your second trimester, estrogen stimulates milk duct development in your breasts.
Estrogen levels then increase steadily throughout your pregnancy, peaking during the third trimester. Thanks to the estrogen increase, your ankles, fingers, and feet may be more swollen than ever during your final trimester.
Progesterone is the second main pregnancy hormone. It's primarily responsible for your uterus growing from the size of a dainty pear to a whopping watermelon.
Aside from expanding your uterus, progesterone loosens your ligaments and joints ready for childbirth. However, loose joints increase the risk of injury while exercising. Always get pregnancy workouts approved by your obstetrician-gynecologist (OB) and take care not to strain yourself.
Like estrogen, your ovaries manufacture progesterone. During pregnancy, the placenta also produces progesterone and supplies these hormones to the fetus. The level of progesterone in your body during pregnancy is incredibly high.
Human Chorionic Gonadotropin Hormone (hCG)
If you're suffering from morning sickness early in your pregnancy, then human chorionic gonadotropin hormone (HCG) may be to blame. The placenta produces hCG during pregnancy; levels rise so rapidly in early pregnancy that they often trigger nausea and vomiting.
hCG's job is to supply your embryo with the nutrients that s/he needs to grow into a thriving baby. Your hCG levels should peak at 8 to 11 weeks and decline later in pregnancy. At this point, other pregnancy hormones (like estrogen and progesterone) take over the important job of providing your baby with essential nutrients.
Low levels of hCG in early pregnancy can indicate serious problems such as an impending miscarriage, ectopic pregnancy, or fetal death. Prenatal screening during early pregnancy can go a long way toward easing your mind and making sure your baby is developing normally.
hCG levels that remain high during the later stages of pregnancy may be an indication of Down syndrome. NTD Eurofins offers several prenatal screening tests that analyze these levels for trisomy disorders, including the Sequential Screen, First Trimester Screen, and Maternal Fetal T1 Screen.
Human Placental Lactogen (hPL)
Human placental lactogen (hPL) is another key pregnancy hormone. It's produced by the placenta to provide your baby's nutrition and stimulate milk glands, ready for breastfeeding.
By the second week of pregnancy, hPL is already busily working in your blood. The hormone levels continue to rise steadily throughout your pregnancy, fulfilling two important jobs.
Firstly, hPL breaks down fats, regulating your metabolism and providing energy for you and your baby. Secondly, hPL makes you insulin resistant, meaning you'll have more sugars in your blood to feed your developing little one.
High levels of hPL can indicate diabetes, so your OB may order an analysis of your hPL levels if you are at risk. Low levels of hPL can indicate preeclampsia, placental insufficiency, or miscarriage.
Relaxin and oxytocin are the pregnancy hormones your body needs to fit that bundle of joy through a very small space. We'll cover relaxin first.
Your ovaries and the placenta produce relaxin. Relaxin levels are typically highest during the first trimester because they prevent your body from having contractions that can lead to premature birth. This pregnancy hormone also loosens the ligaments in your pelvis.
Unfortunately, relaxin is nondiscriminatory about the ligaments it loosens, so it affects all the joints and ligaments in your body. This loosening can lead to lower back and hip pain, which is very common during pregnancy. Toward the end of your pregnancy, relaxin gets to work softening and widening your cervix.
Like relaxin, oxytocin works to prepare your cervix for birth. This pregnancy hormone softens and dilates the opening once it’s time for your baby to make his/her debut. Oxytocin achieves this by creating strong contractions in your body. Once your little one arrives, oxytocin also causes the milk to release during breastfeeding.
Pregnancy hormones can make your life miserable, with nausea, joint and back pain, and even those frequent trips to the bathroom. It's thanks to your hormones, though, that your body is able to grow that little human inside you.
Prenatal screening tests are a great way to make sure your pregnancy hormones are functioning as they should.
Learn more about the screening tests NTD Eurofins offers – then ask your doctor about which tests can help you plan for a healthy, happy baby.
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Pursuant to applicable federal and/or state laboratory requirements, Eurofins NTD, LLC has established and verified the accuracy and precision of its testing services. Tests are developed and performance characteristics determined by Eurofins NTD, LLC. The methods and performance characteristics have been reviewed and approved by the New York State Department of Health.