Ciąża Article · 10 August 2023

The role of progesterone in pregnancy: functions, norms and disorders

Progesterone is one of the most important hormones secreted by a woman’s ovaries. Without its participation, neither getting pregnant nor its subsequent maintenance would be possible. So it is safe to say that progesterone is like a protector standing guard over the safety of our yet unborn child. What exactly does its role consist in? What are the norms for the concentration of this hormone in the body of a woman during pregnancy? And finally, when can we talk about disorders? Are you curious? Read on!

Kobieta w ciąży i jej partner trzymający ręce na brzuchu

What is progesterone and what is its role in pregnancy?


Progesterone is a steroid hormone produced mainly by the corpus luteum and, during pregnancy, by the placenta. Its main task is to prepare the endometrium to receive a fertilized egg. After ovulation, if fertilization does not occur, the corpus luteum degenerates and progesterone levels drop, leading to the desquamation of the endometrium, or menstruation. However, if fertilization occurs and a zygote is formed, the corpus luteum continues to produce progesterone maintaining adequate thickness of the endometrium (endometrium), giving the fertilized egg the best conditions for implantation. In the following weeks of pregnancy (between weeks 7 and 10), progesterone production is taken over by the developing placenta.


Preparing the lining of the uterus for the embryo to implant is, of course, not the only task of progesterone. The hormone prevents the mother’s body from rejecting the fetus by modifying the immune response. In the second half of pregnancy, progesterone is also responsible for relaxing the enlarging uterus and inhibiting its contractile function, reducing its sensitivity to oxytocin and decreasing the production of prostaglandins. In this way, the hormone protects the mother-to-be and her baby from premature labor. However, that’s not all! After childbirth, progesterone levels drop sharply, which stimulates the mammary glands to start lactation. So, as you can see, progesterone in pregnancy performs many important functions that determine its proper course.


Norms of progesterone in pregnancy


The norms of progesterone in pregnancy vary depending on the laboratory where the test was performed. Therefore, when evaluating the result, we should always take into account the reference values given on it. In addition, you should always discuss it with your pregnancy doctor. All right, but let’s get to the specifics already, though. That is, how much progesterone should a pregnant woman’s body produce in each trimester? Here is a sample range of norms:


  • 1st trimester – 11.0-44.3 ng/ml,
  • II trimester – 25.4-83.3 ng/ml,
  • Third trimester – 58.7-214 ng/ml.


Have more questions?
Write or call


Progesterone-related disorders in pregnancy


Disorders of progesterone in pregnancy, specifically progesterone deficiency, can cause a number of pathologies: from problems with implantation of the embryo in the uterus, caused by improper preparation of the endometrium , to bleeding during pregnancy, ectopic pregnancy and the risk of premature labor. Suspicion of the presence of any of the above pathologies is an indication for testing the body’s progesterone levels.


What does low progesterone levels in pregnancy mean?


Low progesterone levels – depending on the age of pregnancy – can suggest either corpus luteum insufficiency or problems with the placenta, which can unfortunately have further consequences. As we have already mentioned, during the period of trying for a child, it can hinder the implantation of the embryo, and thus prevent pregnancy itself. In turn, low progesterone in pregnancy is dangerous for the developing fetus and can lead to a number of complications, including premature birth.

How to raise progesterone levels in pregnancy?

Any mother-to-be whose tests have revealed a progesterone deficiency should start taking the appropriate preparations to help her make up for the deficiency. Of course, never on your own, and only after consulting your doctor! The preparation can be administered by intramuscular, oral or vaginal routes. The form and dose of the drug is also decided by the doctor, after taking into account the clinical situation and the individual preferences of the patient. Raise the level of progesterone in pregnancy can also be done in a more natural way, namely with a properly composed diet. Although progesterone is not found in the composition of any food product available in stores, but by choosing some of them, we can improve our hormonal balance, and thus increase the production of this hormone in the body. So how to increase progesterone levels during pregnancy naturally? First of all, by trying to make sure that the daily menu is rich in such vitamins and minerals as:


  • vitamin C (sources: broccoli, peppers, tomatoes, parsley);
  • VitaminE (sources: sunflower seeds, almonds, mangoes, broccoli, lettuce leaves, pumpkin, asparagus, avocado);
  • Vitamin B6 (sources: tuna, mackerel, salmon, chicken, spinach, walnuts, beans, prunes, bananas);
  • Magnesium (sources: cocoa, cashew nuts, mackerel, whole grain brown rice, chard, black beans);
  • Zinc (sources: beef, lamb, liver, cashew nuts, oysters, shrimp);
  • fiber (sources: wholemeal and whole-grain breads, bran, oatmeal, cereals, groats, nuts, sunflower seeds, pumpkin seeds).


In summary, progesterone plays a key role in pregnancy. It supports her from the moment of conception until delivery, providing the right conditions for the proper development of the baby. Regular monitoring of progesterone levels during pregnancy is essential to minimize the risk of complications such as miscarriage, reproductive tract bleeding, ectopic pregnancy or premature delivery.

Watch us