When It's Time for Fertility Testing

Ordering Blood Tests

There are a number of reasons your healthcare provider will order blood work to help look at your fertility. These tests are performed to:
  • Confirm you have been ovulating
  • Determine ovarian function or reserve (the ability to produce eggs)
  • Measure how receptive your uterus is to pregnancy during the second half of your cycle.
Ovulation can be impaired by changes in the production of a number of things in the body, including but not limited to:
  • Sex hormone binding globulin (SHBG)
  • Follicle-stimulating hormone (FSH)
  • Thyroid-stimulating hormone (TSH)
  • Estrogen
  • Androgens.
Blood tests will be ordered to check your ovarian function and reserve. This will include testing FSH levels early in the menstrual cycle (usually on day 3). If these levels are elevated, it can indicate a diminished ovarian reserve (a decrease in the production of good-quality eggs).
Also on day 3 of your cycle, you may have an estradiol test, which measures the amount of one type of estrogen in your blood. A high level of estradiol indicates poor egg quality.  
Your thyroid also plays an important role in ovulation. Elevated TSH values indicate thyroid failure and a lack of sufficient amounts of thyroid hormone to maintain normal body function. If your TSH value is low, it can indicate an excess production of thyroid hormone. When the TSH value is abnormal, it can impair ovulation and menstruation.
Although these changes in your period or ovulation may be subtle, they may have a profound effect on fertility. Testing your thyroid function is an important part of blood work for testing your fertility.
Another test that may be ordered is a plasma progesterone level, which is a blood test done in the last part of your menstrual cycle to check progesterone levels. High levels of progesterone indicate that ovulation has occurred. Levels of progesterone need to be adequate to stimulate the lining of the uterus to prepare itself for implantation of an embryo.
Your healthcare provider may also order blood tests to measure various other hormones, including prolactin, androgen, and luteinizing hormone (LH).
There may also be situations where your healthcare provider recommends chromosome testing, such as in the case of repeated miscarriages. Also, if you have had repeated miscarriages, your healthcare provider may recommend blood tests to check for clotting disorders and autoimmune disorders that can cause pregnancy loss.
Last reviewed by: Arthur Schoenstadt, MD
4 Relationship Skills for People With ADHD