Periods are defined as irregular when they are less than 21 days or more than 35 days from the start of one cycle to the next. Many patients are often frustrated when they approach their medical doctors for hormone testing and are told that there is no point in testing, rather they should go on the birth control pill. My patients typically prefer to get to the root of the problem and some common blood tests can help point us in the right direction.
- FSH: The optimal range for fertility for FSH is 5 to 7IU/L as measured on day 3 of the cycle. When values of FSH are suppressed this can indicate a condition called hypothalamic amenorrhea. This condition occurs when the brain stops secreting hormones for menstruation. Hypothalamic amenorrhea can be caused by things like stress, low body weight, poor nutrition, not eating enough food and over-exercising. When FSH is elevated this is a sign of peri-menopause or menopause.
- LH: LH is almost always measured alongside FSH on day 3 of the cycle. A suppression in both FSH and LH can again indicate hypothalamic amenorrhea, whereas elevations in LH especially when they are 2x higher than FSH can indicate polycystic ovarian syndrome (or PCOS).
- Estrogen: Estrogen is also tested on day 3 alongside FSH and LH. Sufficient levels of estrogen are required to build a follicle to ovulate. If estrogen is low, we will look to FSH and LH to determine if this could be from hypothalamic amenorrhea or from peri-menopause.
- Prolactin: Prolactin is elevated when breastfeeding, however in some women, prolactin is elevated even when they are not lactating. This can sometimes happen because of a prolactinoma which is a benign tumor located on the pituitary gland, and at times the cause is unknown. Prolactin will decrease FSH and estrogen in the body and can shut down ovulation. This is why many women who are breastfeeding do not get their period. Milky discharge from the breasts when you are not breastfeeding can be a sign of high prolactin.
- Thyroid Stimulating Hormone (TSH): TSH can determine whether your thyroid is functioning normally or not. Although both hyperthyroidism and hypothyroidism can cause menstrual irregularities, it is hypothyroidism that is more commonly associated with irregular periods.
- Testosterone: Testosterone levels are elevated in polycystic ovarian syndrome (or PCOS). Approximately 10% of women have PCOS making it the most common reason for irregular periods. Approximately 80% of women with PCOS have high testosterone due to insulin resistance. As a result, fasting insulin and glucose are often a part of my testosterone work-up as well. It is possible that testosterone levels appear normal in the blood but are still the culprit for irregular periods. This is even more likely when there are other clinical symptoms of high testosterone such as acne, hair growth (on the lip and/or chin), and hair loss. For that reason, when all testing appears normal we often target testosterone.
Irregular periods can result from various underlying factors. Accurate diagnosis is essential to identify the root cause and develop an appropriate treatment plan. Many of the underlying reasons for irregular periods can be treated with dietary changes, lifestyle changes, and supplements (no birth control pills required!).
Dr Ashley von Martels ND is a naturopath in Toronto focusing on Women’s Health. Her areas of interest include: PCOS, irregular periods, acne, interstitial cystitis, UTI’s, yeast infections, PMS, endometriosis, menopause, fertility, pregnancy and preconception (amongst others). She offers virtual consultations to patients across Ontario.
