What produces progesterone?

November 19, 2021

What produces progesterone?

Progesterone is a steroid hormone produced in gonads (ovaries and testes) and the adrenal cortex. The adrenal cortex is the top part of the adrenal glands, which is located above the kidneys. These small organs play an essential role in progesterone production and other vital hormones. Now that we know where progesterone is produced let’s look deeper at what produces progesterone, and its role in the body.

Progesterone Production During the Menstrual Cycle

Progesterone is a natural hormone that comes from cholesterol. It’s a derivative of cholesterol and has numerous functions in a woman’s body, especially for the menstrual cycle and reproductive system. 

A woman’s menstrual cycle on average is 28 days. However, this can be slightly shorter or longer for each woman. The cycle difference is because the ovaries produce less progesterone and more estrogen during the first half of the cycle. But once an egg is released, levels of progesterone increase in preparation for fertilization. 

It also increases the thickness of the endometrium lining inside the uterus. This lining is where the egg will attach if fertilized. However, if the egg isn’t fertilized, levels of progesterone decrease, and estrogen increases once again. This causes the thickened lining to dissolve and release. All of which causes cramping and bleeding, resulting in a period. Progesterone and estrogen also create hormonal side effects like cramping, moodiness, or tiredness.

Progesterone Production During Early Pregnancy

During the first stage of pregnancy (1-10 weeks), progesterone comes from the ovarian corpus luteum. Inside the ovaries (reproductive organs in a woman’s body) are follicles. Each month, a group of follicles builds up with the production of progesterone and estrogen. 

The dominant follicle releases an egg in hopes of fertilization. If the eggs become fertilized, the follicle closes itself off and creates what becomes known as the corpus luteum. In essence, it’s a group of cells that continue to generate progesterone during the initial stages of pregnancy. 


The corpus luteum will continue to excrete progesterone until the placenta is fully formed. The placenta is an organ that forms in the uterus during pregnancy. This organ gives vital nutrients and oxygen to the developing baby and cleans the blood of any waste products in the blood. 

The placenta connects to the uterus wall and grows with the baby’s umbilical cord, which is attached to it. It takes about ten weeks for the placenta to form and connect to the uterus fully. Once this happens, the placenta takes over progesterone production from the corpus luteum. 


The role of progesterone in early pregnancy cannot be understated and has the following supportive effects, including:

  • Increases oxygen levels and blood flow
  • Supports the uterine lining growth
  • Prevents uterine contractions as baby grows

Without progesterone, implantation wouldn’t occur, nor would the embryo be able to grow in the uterus and wait for the placenta to become fully formed. Progesterone makes sustaining healthy pregnancy possible, especially during those early weeks. In addition, it helps prevent miscarriage and preterm labor.

Progesterone Production for Breastfeeding

Progesterone production occurs throughout the pregnancy by the placenta. As mentioned, it helps sustain a healthy pregnancy and prevents miscarriage and preterm labor. But it also has an essential effect on milk production. 

Women begin breastfeeding when a baby is born, but preparation for this event occurs in the months leading up to the birth. The reason is that high levels of progesterone during pregnancy inhibit milk production by preventing prolactin production. Prolactin is a hormone that helps create milk, along with another hormone, oxytocin. 

During pregnancy, estrogen and progesterone help make the breasts bigger and fuller to fill up with milk. Once the placenta comes out after birth, levels of these hormones decrease, and prolactin and oxytocin increase. The suckling of the newborn on the breasts triggers the milk.

Progesterone Production During Menopause


Menopause is a Greek word that means “month” and “pause.” This translation directly states what happens during menopause— your monthly period comes to an end. Typically, this occurs in a woman’s early fifties, but your body is test-driving menopause months and even years before the actual event. 

In essence, menopause comes from lower estrogen and progesterone levels. Since these female hormones regulate the menstrual cycle and fertility, lower levels result in no egg released from the ovaries, no implantation, or monthly period. 

While this may seem significant not to have a period each month, it can bring about uncomfortable side effects. First, you may be saddened by the loss of your fertility, and you may have physical symptoms that become ongoing and difficult to manage. Some of the symptoms include the following: 


  • Hot flashes 
  • Night sweats
  • Moodiness
  • Low sex drive
  • Dry skin
  • Insomnia
  • Depression and anxiety
  • Vaginal dryness
  • Weight gain


For some, these symptoms are mild and easy to manage. For others, the symptoms make daily activities unbearable and hard to manage. Also, menopausal symptoms can go on for weeks, even years, for some women. Menopause is divided into three stages: perimenopausal, menopausal, and postmenopausal. In each one, symptoms can vary as your body begins to live without optimal progesterone and estrogen levels. 

Health Concerns Related to Progesterone


Progesterone is vital for reproduction and fertility, so you may have health concerns if you have low levels. But if you have high levels, this can result in issues as well. Below are some common health issues with progesterone. 

  • Early labor and miscarriage
  • Low fertility rates
  • Breast cancer
  • Granulosa cell tumor
  • Menstrual cycle irregularities


If you’re having symptoms related to low, speak to your healthcare provider about progesterone hormone replacement therapy. Hormone therapy is proven to help many women with low infertility or menopausal symptoms. It’s available over the counter without a prescription.

A common way to supplement is with high-quality progesterone cream. The non-greasy cream comes infused with other natural ingredients to provide a nurturing treatment that boosts progesterone levels while rejuvenating the skin. If your body isn’t producing enough progesterone, you may benefit from supplementing. It’s simple and cost-effective.