What Causes PCOS?
PCOS is caused by High Androgens – Except When it’s Not
By Dr. Pamela Frank, BSc(Hons), ND
PCOS or polycystic ovarian syndrome is a collection of symptoms that affects 8-10% of women of reproductive age. A syndrome is a collection of symptoms, some or all of which may be present. It can present at different times of a woman’s life, meaning things may have all been normal at some point, but later periods may become irregular and hormone imbalance symptoms may appear.
What Causes PCOS?
There is a common erroneous assumption that if a woman presents with symptoms related to PCOS (acne, oily skin/hair, irregular periods, excessive facial or body hair, infertility) that she must have high levels of androgens. This assumption wrongly pigeon holes 40% of women with PCOS symptoms into the category of insulin resistant and high androgen levels. 60% of women with PCOS symptoms do have insulin resistance and elevated levels of DHEAs and/or testosterone. However, the remaining 40% do not. In these women PCOS symptoms have a different root cause that needs to be investigated.
Two Examples of Alternative Causes of PCOS Symptoms
- Hyperprolactinemia (high blood prolactin levels) – Prolactin is a hormone produced by the pituitary to stimulate production of breast milk for breastfeeding. However, prolactin levels can also be elevated due to stress and/or due to a benign pituitary tumor called a prolactinoma. Prolactin interferes with normal ovulation and PCOS-like symptoms arise due to the changes in the normal production of the female hormones estradiol and progesterone.
- Hypothyroidism – An underactive thyroid slows the function and metabolism of all of the body’s cells, including the cells in the ovaries that should be maturing egg follicles into eggs. Irregular ovulation occurs, leading to lower levels of estradiol and progesterone.
How to Know What is Causing your PCOS
The only way to accurately determine whether you have PCOS and why is to perform a complete battery of tests (as appropriate to you and determined by your doctor), that may include:
Fasting blood sugar and insulin
Testosterone – total and free
LH, FSH, and Estradiol (if cycles are present, preferably day 3 of the menstrual cycle)
Progesterone (if cycles are present, preferably 7 days post expected ovulation)
TSH (I prefer a full thyroid screen including fT3, fT4, anti-TPO and anti-thyroglobulin antibodies)
Prolactin (I prefer to see more than one, as the level is variable day to day)
Pelvic and Transvaginal ultrasound
Iptisam Ipek Muderris,a Abdullah Boztosun,b Gokalp Oner,a and Fahri Bayramc Effect of thyroid hormone replacement therapy on ovarian volume and androgen hormones in patients with untreated primary hypothyroidism. Ann Saudi Med. 2011 Mar-Apr; 31(2): 145–151.
Islam S, Pathan F, Ahmed T. Clinical and Biochemical Characteristics of Polycystic Ovarian Syndrome among Women in Bangladesh. Mymensingh Med J. 2015 Apr;24(2):310-8.