Does progesterone rise in pregnancy?

Your pregnancy hormones are constantly in flux from the time you find out you're pregnant until many weeks after giving birth.

Progesterone, often known as P4 and Prog, is a hormone that plays an important role in pregnancy. As such, administering progesterone to women experiencing early pregnancy bleeding and a history of miscarriage, according to research from Tommy's National Centre for Miscarriage Research and the University of Birmingham, may result in 8,450 additional births annually.

Does pregnancy cause a spike in progesterone levels?

Early in pregnancy, the Corpus Luteum cyst found in the ovaries produces the pregnancy hormone progesterone. Up until around ten weeks of pregnancy, the corpus luteum continues to manufacture progesterone before the placenta takes over. 

During pregnancy, this ovarian follicular cyst keeps producing progesterone for ten weeks. After those first few weeks, the placenta starts to produce progesterone on its own. Progesterone levels grow rapidly throughout the first trimester and then plateau. Progesterone is essential in establishing the ideal environment for ovaries to host the developing foetus. It does this by keeping the uterine muscle relaxed and assisting the immune system in tolerating foreign DNA. This pregnancy hormone may occasionally need to be supplied when a woman has IVF or another type of fertility treatment.

Before becoming pregnant:

Early pregnancy produces the hormone progesterone, which primes the uterus for conception. 

How does progesterone aid in preparing the uterus for pregnancy?

It initiates the luteal phase and changes the endometrium (uterus lining) by making it thicker so an embryo can be placed there. When the female egg is fertilised by the male sperm, an embryo is created. The fertilised embryo will typically enter the uterus five days following ovulation if pregnancy is desired. It will then cling to the uterine lining two days later. Progesterone levels peak once it adheres to the uterine wall. Progesterone supplementation is typically used by clients undergoing IVF to aid in promoting the fertilised embryo's attachment to the uterine wall.

When pregnant: Progesterone promotes the developing foetus

Human chorionic gonadotropin hormone (HCG) is produced by pregnant women. The blood and materials that are released during ovulation are delayed by hCG, which also makes it possible for a woman to become pregnant. The foetus is then nurtured as it grows, as progesterone is created. Progesterone production is taken over by the placenta around 8 to 10 weeks of pregnancy and it then grows until the baby is born.

Read more: What to expect when you're expecting.

Progesterone levels:

Less than 1 mg/day of progesterone is produced by the adrenal glands and the ovaries, with the ovaries producing the majority of this hormone before ovulation. This rises to 20–30 mg/day after ovulation with corpus luteum development. 

After then, it rises sharply during pregnancy, peaking at 200 to 400 mg daily at term. Increased progesterone generation is reliant on the corpus luteum up to 7 weeks of gestation, and then the placenta after that, during the so-called "luteal-placental shift," which takes place between 7 and 10 weeks.

First-trimester hormonal changes

Progesterone and oestrogen, which are normally present during your menstrual cycle, increase significantly when you first get pregnant. Additionally, a new pregnancy hormone called human chorionic gonadotropin, which is unique to pregnancy, starts to be generated.

Second-trimester hormonal changes

Progesterone and oestrogen continue to rise during the second trimester to aid in the development of the foetus. However, these hormones also activate the hormone that stimulates melanocytes. It causes the melanocyte cells on your skin to begin producing melanin, which imparts your skin colour. The "mask of pregnancy," also referred to as melasma, which develops dark or grey patches all over the face, may become apparent in some women as a result.

Third-trimester hormonal changes

During this trimester, your baby is beginning to gain weight, and the body is boosting other hormones it will require after giving birth. Your oestrogen levels are at their maximum throughout this trimester—six times greater than they were before pregnancy—and progesterone levels peak around 32 weeks.

What happens if you have low progesterone levels?

According to doctors, some pregnant women are at risk for luteal phase insufficiency (meaning they produce insufficient amounts of progesterone), especially those with very low body fat or marginally low body weight (BMI of 19 or less); women who exercise more than four hours per week; women who have previously lost their menstrual periods as a result of stress; and women who are brief luteal phase.

How to Naturally Raise Low Progesterone Levels

Uphold a healthy weight

First, some background information: progesterone and oestrogen maintain the body in balance. Extra oestrogen can be produced in fat cells as a result of increased body fat. It does contribute to maintaining normal oestrogen levels, which maintains a suitable progesterone-oestrogen ratio.

To avoid overtraining

Normal, moderate activity is beneficial to both you and your unborn child and won't negatively affect progesterone or oestrogen levels.

Reduced tension

According to the study, the habit of periodically switching to positive emotions provides a signal to the adrenals that they may restore proper activity and cease the conversion of progesterone to cortisol, according to the study. 

Read more: How to increase progesterone.

The negatives of progesterone:

All of the body's smooth muscle, most significantly the muscle membrane of either the uterus or "womb," is relaxed by progesterone. It also causes the blood vessels throughout the body to relax, resulting in lower-than-normal blood pressure, irregular heartbeat, occasional fainting and gastrointestinal symptoms including heartburn, reflux, burping, nausea, puking, gas, and constipation. Additionally, progesterone can promote hair growth. Unwanted hair could be visible, for instance, on your lower belly and breasts.

Bottom Line: 

To prepare the uterus for pregnancy, higher progesterone levels are required. This ovarian hormone encourages the formation of blood vessels after implantation, laying the groundwork for a functional placenta. Progesterone continues to work hard to maintain a healthy uterus and aid in preventing premature birth even when the placenta assumes control. Your progesterone levels must remain high during your pregnancy for this reason.

Order a Welzo Progesterone at-home test here.