Progesterone is a key hormone to the menstrual cycle and pregnancy. Here’s everything you need to know about what this hormone does and its typical levels—and how to measure yours.
Progesterone is a multi-purpose hormone and a staple in menstrual regulation in women’s bodies.
Knowing what progesterone does and how to interpret your progesterone levels can offer you insight into your reproductive health and overall well-being.
Here’s what you need to know about progesterone function, low and high progesterone level signs, typical progesterone ranges, and how to measure your progesterone levels.
What does progesterone do in a woman’s body? Progesterone is a hormone produced in the ovaries after ovulation that plays a key role in preparing the uterus for pregnancy. If pregnancy happens, progesterone levels rise to help prepare the body to support it. If pregnancy does not occur, progesterone levels will drop, along with estrogen, leading to menstruation.
Progesterone also has ties to cardiovascular health, mood regulation, bone health, and more.
Cardiovascular health Bone health What does progesterone do in the menstrual cycle? Progesterone plays a significant role in the second part of the ovarian cycle: the luteal phase.
The luteal phase begins right after ovulation and lasts around 11-17 days, ending with either the first day of your period or the beginning of pregnancy. After ovulation, a temporary endocrine gland in the ovary forms called the corpus luteum. The corpus luteum then releases progesterone and estrogen, which builds up the uterine lining—preparing the uterus for a potential implantation of a fertilized egg.
What happens to progesterone if you get pregnant? If sperm successfully fertilizes the ovulated egg in the fallopian tube, the fertilized egg will implant in the uterine wall and begin releasing a hormone known as hCG (the hormone detected by pregnancy tests). This hormone plays a vital role in maintaining the corpus luteum, ensuring it continues to produce progesterone and estrogen.
Therefore, if an egg is fertilized, progesterone continues to stay high.
>>RELATED: How to Increase Progesterone to Get Pregnant: 5 Ways
What happens to progesterone if you don’t get pregnant? If sperm does not fertilize the ovulated egg, the corpus luteum does not receive the signal to maintain progesterone production. As the corpus luteum shrinks, levels of progesterone and estrogen decrease. This drop signals the shedding of the uterine lining, resulting in menstruation, and marks the beginning of a new cycle.
How do progesterone levels affect the body? Progesterone levels fluctuate throughout the cycle, and everyone reacts differently.
How low or high your progesterone levels are can depend on where you are at in your menstrual cycle, pregnancy, menopause, hormone therapy, or medical conditions like adrenal gland disorders.
Women many experience symptoms through changes in:
Mood Energy levels Breast tenderness Sexual desire Sleep Fluid retention It’s common to feel these symptoms as progesterone is fluctuating, not just when levels are high or low. For example, some women experience more fatigue, acne, and bloating during the later phases of the menstrual cycle when progesterone levels are high, and more anxiety or depression during the late luteal phase right before menstruation—when progesterone levels drop off significantly.
How does progesterone affect your emotions? Progesterone helps create allopregnanolone (ALLO), which acts on gamma-aminobutyric acid (GABA) receptors and has a calming effect.
While progesterone can be calming, it can also lead to anxiety. Individuals with premenstrual dysphoric disorder (PMDD) can have negative mood reactions to hormone fluctuations, and instead of “sedating,” GABA receptors progesterone might stimulate them.
Additionally, at the end of the luteal phase (right before menstruation), progesterone levels drop. According to the Massachusetts General Hospital Center for Women’s Health with Harvard Medical School , exposure to progesterone/ALLO and the rapid withdrawal from the ovarian hormones during the late luteal phase plays a role in the etiology of PMDD.
ALLO is known to provide relief, but in women with PMDD, ALLO increases do not occur, or their body receptors are more sensitive to the rapid withdrawal of the hormones.
Low progesterone levels Low progesterone levels can be associated with various symptoms, from physical changes to emotional challenges.
Some low progesterone symptoms are:
Irregular cycles Missed periods Light bleeding/spotting between periods Recurrent miscarriages Trouble getting pregnant Mood swings Increased anxiety Depression Sleep disturbances Weight changes Headaches Hot flashes Breast tenderness >>RELATED: What are low progesterone symptoms?
Low progesterone and luteal phase defect If the ovaries don’t produce enough progesterone after ovulation, it may lead to luteal phase defect (LPD).
Luteal phase defect (LPD) is when the luteal phase is too short to support the uterus lining for a fertilized egg to attach and grow. This can happen because not enough progesterone is being made, or the uterus is not reacting to normal progesterone levels. A short luteal phase—when you get your period too soon after ovulation—is usually a sign of LPD.
Research has shown that isolated cycles with a short luteal phase are common. Yet if you're tracking your menstrual cycle and notice consistent luteal phases being less than ten days, (about one and a half weeks) talk to your healthcare provider.
Short luteal phases make it difficult for the body to have enough time to create a supportive environment in the uterus with enough nutrients for an implanted egg to thrive. However, research has shown that while short luteal phases might impact short term fertility, fertility at 12 months is not lower for women with shorter luteal phases, and consecutive short luteal phases only occurs in about 3% of women.
Some causes of consistent short luteal phases include endometriosis, PCOS, thyroid disorders, obesity, anorexia, stress, excessive exercise, inadequate nutrition, and some medications (e.g., hormonal birth control). Lengthening the luteal phase could include addressing underlying these reasons for low progesterone or short luteal phases.
High progesterone levels The most common cause of elevated progesterone is pregnancy. As the pregnancy progresses, progesterone levels steadily increase to support the growing fetus.
However, you may also have high progesterone because of hormonal medications, such as birth control or hormone replacement therapy , ovarian cysts, and congenital adrenal hyperplasia (CAH).
Some symptoms of high progesterone are:
Irregular periods Mood changes Increased anxiety, depression, or irritability Breast tenderness Breast swelling Weight gain Fatigue Bloating Constipation Nausea Lightheaded or drowsy Acne Changes in sex drive What are normal progesterone levels? Progesterone fluctuates throughout your cycle—and throughout your life! While we know progesterone rises after ovulation, there are also changes in progesterone levels when you’re in perimenopause vs. pre-perimenopause, for example.
>>RELATED: Everything You Need to Know About Progesterone During Perimenopause
Here are typical progesterone levels in (ng/mL) that you can expect during different phases of your life.
Prepuberty: 0.1-0.3Menstruating (follicular): <0.89 Menstruating (ovulation): <= 12 Menstruating (luteal): 1.8-24Pregnancy (trimester 1): 11-44Pregnancy (trimester 2): 25-83Pregnancy (trimester 3): 58-214 Perimenopause (follicular): 0-1 Perimenopause (luteal) : 0.48-19 Post menopause: 0-0.5 How to measure your progesterone levels There are a few different ways you can measure progesterone levels:
Blood tests give you a direct measurement of progesterone by looking at your blood levels.Urine tests use a hormone metabolite to get the same information. Hormone metabolites are byproducts that represent what your body has excreted over time. >>RELATED: How are LH, Progesterone, and Estrogen Measured?
P4 is the pre-metabolized version of progesterone that is measured in the blood (ng/mL), whereas PdG is the post-metabolized version of progesterone found in the urine (ug/mL). ng/mL is used to measure substances present in lower concentrations in the blood and other biological fluids. Since metabolites are found in higher concentrations, ug/mL is used because it is a more manageable unit.
Think of PdG as honey produced by the honeybees, P4, from pollen. Honey (PdG) is a quantifiable and tangible measurement of the bee's work over a period of time. The amount of honey can indicate the efficiency and activity of the honeybees (P4).
Essentially, both tests—and ways of measuring—can give you a good idea of what your hormone levels are over time. It just depends on what snapshot of your hormones you’re looking for, and what kind of test you’d like.
Progesterone: the bottom line Progesterone is an important hormone with diverse roles in women’s health, reproductive processes, mood regulation, and well-being. Understanding its function from preparing the uterus for pregnancy to supporting emotional stability and cardiovascular health, shows its necessity for hormonal balance.
While low progesterone levels can lead to fertility issues, elevated levels can bring fatigue, acne, along with other symptoms.
Tracking progesterone across various stages is beneficial in addressing imbalances and to better prepare for the various points of the menstrual cycle. Oova can help you understand the complexities of your unique hormone profile and empower you to navigate your hormonal health confidently.
.png)
