Do you have no idea when your next period will show up? It’s unpredictable and on its own schedule, either coming every few weeks or every few months. What’s up with that??

Worrying about when your next period will make an appearance—on a first date, during an important meeting, or on vacation—is something that no one is interested in. Not to mention having to deal with cramps, cravings, fatigue, and those crazy mood swings! It just doesn’t seem right.

And while you may feel like you’re the only one dealing with it, between 11 and 13 percent of women have irregular periods.

So, you’re not alone sister!

What is a normal cycle length?

What may surprise you is that a “normal” period doesn’t necessarily have to start every 28 days.

Practitioners differ regarding what constitutes a normal menstrual cycle length, with studies showing that a healthy cycle can fall within the range of 21 to 35 days, with an average period length of 3-7 days.

However, in my professional experience, a 25-to 35-day cycle is ideal for optimal hormone health and fertility. Women I’ve worked with over the years with cycles shorter than 24 days tend to have lower progesterone or excess estrogen and too-short luteal phases, which can impair their ability to get pregnant. So, while these shorter cycles might technically be considered “healthy,” remember that fertility and menstrual health are intricately tied together.

While pregnancy might not be your endgame, it is your body’s, and a truly healthy cycle is one that gives your body a chance to reach this goal. In my experience, this is achieved with a 25-to 35-day cycle.

Although some variation with your period can happen due to food and lifestyle changes, if you have irregular periods or changes in your period that persist for several months, it’s always a good idea to see your OB/GYN. She might suggest you take the pill to regulate your periods, but what you really need to know is why they’re irregular in the first place. That’s why you’re reading this!

5 Common Causes for Irregular Periods

1. Polycystic ovary syndrome (PCOS) may be to blame for your irregular periods.

PCOS is an inflammatory endocrine disorder that prevents the ovarian follicles from reaching the ovulation stage, causing significant delays in ovulation (or even preventing it) which then causes irregular or nonexistent periods.

It affects over 100 million women worldwide making it the most common endocrine disorder in women of reproductive age and the leading cause of ovulatory infertility.

Women with PCOS tend to have too much estrogen and testosterone (an androgen), which disrupt normal ovulation, leading to lowered progesterone.

Here’s how that happens: An egg is typically released by your ovaries to be fertilized every month, but women with PCOS run into problems with this process because they tend to have blood sugar and insulin dysregulation.

Excess insulin raises LH which causes the ovaries to produce more androgens (such as testosterone), and less of the estradiol and estrone they usually make. And when ovaries produce excess testosterone, the entire feedback loop between your brain and ovaries gets interrupted, and your eggs are not able to grow adequately and, ultimately, be released.

Instead, the follicle (often referred to as a cyst) stays in the ovaries where it can be seen via ultrasound. Cue sporadic ovulation or lack of ovulation.

Without ovulation and the hormonal events leading up to it, your uterus does not have the stimulation it needs to shed its lining consistently. Hence, no period! Or irregular periods. This is why infertility can be an issue with PCOS. If you’re not ovulating, you’re technically considered infertile.

Aside from sometimes having “cysts” on their ovaries, women with PCOS also commonly see symptoms like excessive hair growth (especially on the face), acne, and weight gain—and are also more likely to struggle with insulin resistance and type-2 diabetes.

To read more about PCOS and how to treat it naturally, check out this post.

2. Thyroid dysfunction can lead to irregular periods.

An underactive (hypothyroid) or overactive thyroid (hyperthyroid), Graves’ disease, Hashimoto’s thyroiditis, or a postpartum autoimmune thyroid condition could all cause your periods to be irregular because the thyroid heavily influences ovulation and your menstrual cycle. Who knew?!

I most often see hyperthyroidism and/or Grave’s disease triggering irregular cycles because these conditions raise SHBG which lowers circulating levels of estradiol. Lower estradiol disrupts the feedback loop between your ovaries and your brain, so that your brain doesn’t send the correct amount of FSH and LH to your ovaries.

To go more in-depth on how your thyroid affects your hormones, check out this blog post.

If you have irregular periods, it’s always a good idea to see your doctor and rule out thyroid dysfunction. Make sure your doctor runs a full thyroid panel. See my blog post on the thyroid to get optimal test ranges.

  • Thyroid Stimulating Hormone (TSH)
  • Free Thyroxine (FT4)
  • Free Triiodothyronine (FT3)
  • Thyroglobulin Antibodies (TGAB)
  • Thyroid Peroxidase Antibodies (TPO/TPEX)

This test from Lets Get Checked will give you a complete picture of what’s going on in thyroid land, and provide you with results in 2 to 5 days. (Use code Hormones20 to get 20% off the price of the test!)

3. Stress can cause irregular periods.

Surprise! Haha, I kid. For reals though, most of us are chronically stressed and don’t even realize it.

The sad reality of the situation, however, is that ongoing stress can lead to HPA axis dysfunction, disrupted cortisol secretion, and irregular or absent periods.

In order to better understand how this happens, we first have to talk about the main players involved in our body’s stress response. The hypothalamic-pituitary-adrenal (HPA) axis coordinates our body’s stress response: The brain (hypothalamus + pituitary glands) signals the adrenals to secrete hormones like epinephrine and cortisol in a perfectly orchestrated pattern that helps us respond to stressors. This is a good thing if it occurs only every once in a while.

When we’re in a state of chronic stress, however, this pattern can easily become disrupted, resulting in adrenal hormone dysfunction.

But how does this dysfunction mess with our reproductive systems, exactly? ⁠It’s a bit of a top-down domino effect.

First, high cortisol brought on by stress dampens the hypothalamus’s gonadotropin releasing hormone (GnRH) secretion, which is responsible for triggering the pituitary to release follicle stimulating hormone (FSH) and luteinizing hormone (LH).⁠ This is bad news, because FSH and LH are critical for reproduction: FSH stimulates the ovarian follicle, causing an egg to grow, and triggers the production of estrogen in the follicle. The release of LH then causes the egg to be released from the ovary (known as ovulation).

But that’s not all…

Similarly to its effect on GnRH, cortisol also directly inhibits the production of FSH and LH in the pituitary in a further attempt to thwart the chance of ovulation and potential pregnancy.⁠ As a result, over time, the production of estrogen, progesterone, and testosterone goes a little haywire, thus disrupting the entire menstrual cycle.⁠

Ongoing activation of our body’s stress system and higher levels of stress-related hormones are directly linked with anovulatory cycles or irregular ovulation—which can show up as irregular periods or hypothalamic amenorrhea (HA) in some women, or heavier periods and spotting in others.⁠

The best thing you can do for your period? Figure out ways to build in RELAXATION into your days.

4. Primary Ovarian Insufficiency (also known as Premature Ovarian Failure)

If your period’s missing, Premature Ovarian Insufficiency (POI) may be to blame. Also known by the name Premature Ovarian Failure, this condition results in your period all but coming to a halt.

This is basically a complicated way of saying your ovaries have stopped functioning properly well before you’re close to reaching menopause (under the age of 40). It’s not a premature menopause, but a malfunction that results in your ovaries not releasing eggs regularly. Women with POI can and do get pregnant (although often with great difficulty). They can sporadically ovulate. For this reason, researchers are suggesting it’s really more accurate to refer to this condition as Primary Ovarian Insufficiency rather than Primary Ovarian Failure.

Because ovulation dysfunction isn’t something that we typically associate with glaringly obvious symptoms, and we can’t see if it’s happening or not, POI is often diagnosed in the later stages of the condition. However, certain risk factors for POI exist, and autoimmune disorders are one such risk factor, particularly adrenal autoimmune diseases like Addison’s and autoimmune thyroiditis like Hashimoto’s. It has been associated with a number of other autoimmune conditions too.

POI is also associated with low levels of estrogen and androgens. Since the body isn’t ovulating regularly, hormone levels are not optimal. One of the early signs of POI can be vaginal dryness, or lowered vaginal fluid levels, since decreases in estrogen typically produce this symptom. Likewise, hot flashes, night sweats, or low libido can be telltale signs that POI is presenting. Sometimes, these symptoms are masked by hormonal birth control, and women are surprised after going off birth control that they don’t regain normal ovulatory function.

Some research indicates that decreasing inflammation via the administration of corticosteroids can induce ovulation in women with POI. Scientists have also explored the possibility of using human amniotic epithelial cells (hAECs) to restore ovulation in mice.

So if the research shows that decreasing inflammation via corticosteroids can induce ovulation, then in my opinion, what needs to happen as a first step is holistic nutrition and lifestyle intervention to decrease inflammation naturally. I literally cannot stress this enough. 

You are at higher risk for POI if you have an autoimmune disease which is very much connected to an underlying inflammatory state. The health of your gut and its ability to absorb nutrients, as well as your liver and its ability to break down and remove toxins from your body play a critical role in how inflamed you are. And your ovarian tissue is some of the most sensitive tissue in your body – it is affected by nutrient deficiencies, environmental toxins and inflammation – so it is crucial that the contributing factors to POI are addressed immediately.

Untreated premature ovarian failure increases the risk of osteoporosis, cardiovascular disease, dementia, cognitive decline, and Parkinsons, all associated with declining levels of protective estradiol and progesterone.

Whether you doing my Fix Your Period Program or work with someone, please know that making these changes can help tremendously.

5. Nutrient Deficiency – vitamin D, Magnesium, Vitamin C, Zinc & Selenium

Optimal vitamin D levels are critical for health, and healthy periods are no exception here.

Adequate vitamin D levels have been linked to proper ovarian function. As such, Vitamin D seems to increase progesterone production. And it is believed that vitamin D has a direct effect on AMH anti-mullerian hormone production, therefore the belief is that someone with higher vitamin D levels would be able to maintain their ovarian reserve for longer. 

A vitamin D deficiency has also been shown to increase androgens and decrease estrogen levels. It’s also linked to PCOS, fibroids, and PMS.

Vitamin D deficiency is pretty common, too. Researchers have been classifying it as an epidemic for decades now. And we’re not exactly trending towards spending more time outdoors getting the sun exposure needed to naturally ramp up those levels of vitamin D.

If you suspect your vitamin D levels may be to blame for your missing period, ask your doctor to test or get a test kit on Let’s Get Checked – use code Hormones20 to get 20% off the price of the test. And then get outside and enjoy some sunshine!

Magnesium support the COMT enzyme in the liver, whos job it is to help remove estrogen from the body properly. When estrogen is properly cleared from the body, you avoid estrogen dominance or estrogen excess which is associated with PCOS and irregular cycles. 

Ascorbic acid or vitamin C is associated with higher progesterone which is why vitamin C supplementation can increase progesterone.

I want to give a shout-out to zinc, which helps the follicles in the ovaries mature each month.57 It also improves PCOS-related issues like insulin resistance and high testosterone.58 Additionally, zinc supports thyroid hormone production.

Selenium is found in large quantities in healthy egg follicles and plays a critical role in the later stages of follicle development.


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