In conversations about the menstrual cycle and female hormonal health it is often that oestrogen gets the first mention over progesterone. Yes, oestrogen is a dominant female hormone, although progesterone is just as important and shouldn’t be overlooked in menstrual cycle or fertility education.

Progesterone is often referred to as the pregnancy hormone and its name means just that. Originating from the Latin word pro gestationem – meaning, in favour of pregnancy. Its benefits for a healthy pregnancy are essential, however progesterone also provides benefits beyond this. Read on to get the DL on progesterone and ways to support this underdog hormone.


What is Progesterone? 

Progestogens, like oestrogens and androgens, are synthesised from cholesterol through a process called steroidogenesis at endocrine organs, such as the gonads (ovaries) and the adrenals. Progesterone is a female sex steroid hormone a part of the progestogen group that is secreted by the corpus luteum – a normal cyst that forms in the ovary after the release of an egg - following ovulation. This secretion is known as luteal progesterone secretion as it occurs during the luteal phase.  


So why is progesterone known as the pregnancy hormone? Progesterone essentially prepares the endometrium – lining of the uterus – for implantation of a fertilized egg, decreases uterine contractility and maintains a healthy gestational sac that is vital for the first weeks of embryonic development. Research has shown that low progesterone secretion is associated with miscarriage and administration with sufficient progesterone may prevent spontaneous miscarriage. During pregnancy, progesterone is secreted by the corpus luteum until around 10 weeks where secretions are then maintained by cells of the placenta known as trophoblasts.




Regulates the Cycle

Women are told that the main aim of the menstrual cycle is to have a period, however it could be argued that the main aim is to ovulate. Regular mid-cycle rises in progesterone signify that ovulation has occurred as progesterone secretion reaches its peak following ovulation, around day 21 of the cycle. This rise in progesterone is not only important in preparation for pregnancy but for vascularization, blood flow and increasing the mucous lining in the cervix. When fertilization doesn’t take place, progesterone levels fall due to the breakdown of the corpus luteum causing the shedding of the endometrial lining – a period.


Manages PMS

Premenstrual syndrome (PMS) is a common occurrence in around 5% of menstruating women that occurs in the late luteal phase. If you experience PMS, common symptoms include increased anxiety, mood swings, food cravings and cramps. It has been suggested that PMS correlates with insufficient progesterone secretion or due to the sudden drop in progesterone during the luteal phase. In women with low progesterone levels increasing vitamin C – or ascorbic acid – intake is recommended as it is seen to increase natural progesterone production. Boosting your intake through vitamin C rich foods like citrus, tomatoes and berries are a good place to start. Or try our newest product Active Cycle that contains acerola berry powder - a super-rich source of ascorbic acid and antioxidants that support healthy progesterone levels.   


Is Cardioprotective

Progesterone, like oestrogen, has direct cardioprotective effects. From lowering blood pressure, inhibiting coronary artery spasms or preventing heart attack, and acting as a strong vasodilator. Beneficial effects of female sex hormones on protecting cardiovascular health are evident where premenopausal women have a significantly reduced risk of cardiovascular complications than that seen in men or postmenopausal women. 


Supports Bone Health

Oestrogen and progesterone both play major roles in promoting bone health. There is a link between the differing levels of hormones during a menstrual cycle with bone resorption and formation. The higher levels of oestrogen seen during the follicular phase are associated with regulating bone turnover and high levels of progesterone after ovulation promote bone formation. Findings show that deficiencies of progesterone causing ovulation abnormalities causes a decreased ability to reach peak bone mineral density. Supporting the proper functioning and levels of these hormones during premenopausal years is vital for preventing serious cases of bone complications post menopause when sex hormones go MIA.  


Signs of Low Progesterone

Navigating menstrual and hormonal irregularities can be tricky and frustrating. Although, symptoms are often more commonplace than most think.


Infertility – A common symptom being having trouble falling pregnant. When progesterone levels are insufficient its benefit as a pregnancy hormone diminishes due to reduced endometrial lining support that results in impaired implantation of a fertilised egg.


Irregular Menstrual Cycles or Oligomenorrhea – A regular menstrual cycle is described as having a cycle length of anywhere between 21-35 days. Anything longer or shorter than these cycle lengths or experiencing fewer cycles per year are red flags that something is going on with your hormones. If your cycle varies in length significantly each cycle it may be time to seek professional help.


Recurrent Miscarriage – Similar to infertility, when progesterone levels are low and endometrial lining is compromised, nourishment to the growing embryo is suboptimal. Progesterone insufficiency also increases uterine contraction which can increase miscarriage risk or premature delivery.


Spotting – Also known as intermenstrual bleeding, can signify low progesterone and a possible luteal phase defect (LPD). An LPD is usually recognised as a short luteal phase lasting < 9 days before the onset of menstruation with light spotting. Women may experience small bleeds a few days out from their period that may only require a liner not a heavy bleed.


Understanding the significance of our cycles and sex hormones - other than just causing a monthly bleed – is empowering. Hopefully putting progesterone in the spotlight has given insight to this mighty hormone and its benefits beyond the bleed!


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