The menstrual cycle is controlled by four key hormones: Luteinising hormone (LH), follicle-stimulating hormone (FSH), oestrogen and progesterone. Each of these hormones plays a different, albeit equally important role in regulating the different stages of the menstrual cycle and keeping things ‘in rhythm’. Oestrogen in particular is one hormone that gets a lot of attention, and the term ‘oestrogen dominance’ is one that has seen increasing usage in recent years. Unfortunately however, oestrogen often gets a bad name in the media, but it plays some incredibly important roles in the body! In this article today, we’ll explore some of these roles, and take a closer look at what it might mean to be ‘oestrogen dominant’.
What Does Oestrogen Do In The Female Body?
While oestrogen is found in both men and women, it’s considered the primary ‘female sex hormone’, as it’s responsible for the development of secondary sexual characteristics in females, such as breast tissue. Oestrogen is also involved in the maintenance of healthy cholesterol levels and in promoting healthy bone density in women. For those interested in conceiving, adequate oestrogen levels are required to ensure the development of a healthy and thick uterine lining, to allow for implantation of the embryo. Oestrogen also helps keep our skin soft and subtle as we age, which is why declining oestrogen levels during menopause can be associated with dry skin. It also helps lubricate the vagina and increases insulin sensitivity, which is important for healthy weight management. As you can see, oestrogen plays many important roles in the body, but sadly, it often gets a bad rap!
Oestrogen Levels Should Fluctuate Throughout the Menstrual Cycle!
It’s important to know that oestrogen levels should fluctuate quite significantly throughout the menstrual cycle – in fact, persistently low oestrogen levels are often a cause of missing or irregular periods. In a typical four week cycle, oestrogen starts out low, with the onset of your period. Over the first two weeks of your cycle, oestrogen starts to climb, eventually reaching a peak around days 12-14. This spike in oestrogen (together with a surge in LH) triggers ovulation. From this point, oestrogen drops quite significantly, followed by a small, secondary rise in the mid-luteal phase (about a week after ovulation). From here, it continues to decrease until the onset of the next menstrual cycle.
What Is Oestrogen Dominance?
The term ‘oestrogen dominance’ describes a theoretical or perceived imbalance in the ratio of oestrogen to progesterone in the body, arising due to an excess of oestrogen, inadequate progesterone production, or a combination of the two. It’s important to know that ‘oestrogen dominance’ is not a medical diagnosis, but rather, a term used to describe a state of hormonal dysfunction or imbalance, often occurring due to issues with oestrogen metabolism. Signs that may be indicative of a high oestrogen-to-progesterone ratio include:
- Pre-menstrual moodiness, irritability or weepiness
- Sore breasts prior to menstruation
- Heavy periods (menorrhagia)
- Painful periods (dysmenorrhoea)
- Fluid retention prior to menstruation
- Fibrocystic breasts
It’s also important to know that many of these symptoms can be caused by a variety of factors, and hormonal dysfunction or imbalance is just one of those factors that needs to be considered. If oestrogen metabolism issues are suspected, we then need to determine why.
High Oestrogen (Or Oestrogen Excess)
High oestrogen can occur for a variety of reasons, but it often comes down to excessive oestrogen production or poor oestrogen clearance. One of the major causes of excessive oestrogen production is being overweight. In fact, body fat is considered hormonally active tissue, as within every fat cell in the body, there is an enzyme called aromatase, which converts testosterone into oestrogen. For this reason, carrying excess body fat can contribute to higher oestrogen levels, resulting in heavier and more painful periods, along with some of the other signs of ‘oestrogen dominance’. Endocrine disruptors, such as BPA, can also contribute to high oestrogen levels, due to their oestrogenic effects.
Oestrogen is metabolised in the liver and bowels, so these organs need to be functioning well in order for oestrogen to be properly cleared from the body. For example, conditions like constipation can result in recycling and reabsorption of oestrogen from the digestive tract, contributing to issues like oestrogen excess. There are a host of other factors that can contribute to oestrogen excess as well (such as nutritional deficiencies, compromised thyroid function and dysbiosis), so all of these factors need to be considered in cases suggestive of oestrogen metabolism issues.
One of the other causes of a high oestrogen-to-progesterone ratio is low progesterone. There are many factors that can cause or contribute to low progesterone, including nutritional deficiencies (specifically of nutrients like zinc, certain B vitamins and iodine), thyroid disorders, stress or being underweight. It’s also important to know progesterone is only produced once we ovulate, meaning failure to ovulate means there is little to no progesterone available to counter the effects of oestrogen.
Another sign of low progesterone is a short luteal phase (the time between ovulation and menstruation). Typically a healthy luteal phase is around 12-14 days, however low progesterone can be associated with a shorter luteal phase (e.g. 10 days or less). This is something that needs to be explored and addressed, especially so for women hoping to conceive in the near future.
The Take Home
Ultimately, there are many factors that influence the state of our hormones, in particular, the balance between oestrogen and progesterone. The concept of oestrogen dominance is a complex issue and sadly, oestrogen often gets a bad rap because of it! Oestrogen plays many important roles in the female body but in menstruating women, it needs to be balanced by healthy levels of progesterone to keep things in sync. If you suspect issues with oestrogen metabolism or are experiencing other signs of hormonal imbalance, we recommend checking in with your naturopath who can help you explore your symptoms further and get to the bottom of any hormonal issues or imbalances that might be occurring.