Basic Fertility Testing in Your 30s
If you're approaching your mid 30s and are starting to think about kids, you may want to consider getting some of your hormones tested. You might be thinking, "My periods are like clockwork, isn't that good enough?" Maybe - but having regular periods doesn't truly give us a glimpse of your hormones.
As we age, our hormones begin to change, and it can take longer to become pregnant. Normally it's recommended that people under 35 seek care (ie. go to a fertility clinic) if they've been trying for about 12 months without a live birth. If you're over 35, then it's recommended that you seek care if you've been trying for 6 months without a live birth.
It's been my experience in practise where couples under 35 don't want to wait out that full year before they begin to seek out help. Measuring basal body temperature, assessing cervical fluid, using ovulation predictor kits, timing sex, and the two week wait can be really stressful - and after a few months of unsuccess, people are ready for answers.
Many people think that fancy tests need to be done to get an assessment about fertility - and that isn't true. I like looking at blood work because it gives us an idea of what's going on upstream (aka. in the brain). Whereas urinary metabolites looks at the downstream products. Ideally, we want to see how the pituitary gland is functioning, not the different types of estrogen metabolites (which won't really tell us anything about what's going on fertility-wise). Not to mention, fertility clinics aren't using urine tests to guide their treatments, they're using serum (aka. blood).
Basic Fertility Assessment
If you're wanting to get some basic tests done potentially before visiting a fertility clinic, here's what you should consider. All of these tests can be ordered by Naturopathic Doctors.
FSH (Follicle Stimulating Hormone)
FSH is a hormone that stimulates ovarian follicles to grow and develop. In some women, the pituitary secretes a lot of FSH to encourage the ovary to respond. When this begins to happen, it's usually due to a decline in ovarian reserve (the total number of gonadotropin-responsive follicles and oocytes within a person's ovaries at any given time), and we would typically start to suspect this when the FSH is over 10mIU/mL.
FSH should be tested on day 3 of your menstrual cycle.
Estradiol
This is a form of estrogen that is typically measured early on in your cycle in conjunction with FSH and AMH as a means to assess your ovarian reserve.
Estradiol should be tested on day 3 of your menstrual cycle.
AMH (Anti-Mullerian Hormone)
AMH is produced by the granulosa cells surrounding each oocyte in developing ovaries, and serves as a marker of ovarian reserve as it reflects the size of the follicle pool. An AMH greater than 0.8-1.0 ng/mL is suggestive of a normal ovarian reserve.
It's important to be mindful that AMH does not accurately predict the chance of pregnancy in people who are not infertile. A single test will not predict time to pregnancy - meaning you could have an optimal level, and it can still take a few months to become pregnant.
Moreover, studies have been done in women with low serum AMH, and the monthly ability of pregnancy compared to women with normal AMH levels did not differ. That said, this test is commonly run in women considered to be infertile as it is useful for prediction of the ovarian response to ovulation induction and controlled ovarian hyperstimulation.
Some docs will run this test right away, and some will wait. In people with PCOS, this number may be high. If we find that it's low, however, sometimes prompted treatment is warranted. There does appear to be a seasonal variability with AMH, where low levels of vitamin D may be one of the reasons for low AMH.
While AMH can be tested anytime during your cycle, it's best to run it at the same time with FSH and estradiol.
TSH (Thyroid Stimulating Hormone)
An association between thyroid health and fertility exists. Thyroid conditions like hypothyroidism and Hashimotos can contribute to a wide array of fertility issues like no period, recurrent miscarriage and prolonged spotting.
Ideally, getting a WHOLE thyroid panel done would be ideal - this includes, TSH, T3, T4 and thyroid antibodies. But sometimes only TSH should be run. The target for TSH should be between 1-2.
If you think IVF may be part of your family plan, a study has shown that hypothyroid women are less responsive to ovarian stimulation and have a lower rate of embryo transfer.
Thyroid hormones can be tested anytime during your cycle.
What About Egg Quality?
The important thing to remember about these tests is that while they provide some good information, they don't tell you about egg quality. A reproductive endocrinologist on a podcast I listened to used an example of keeping eggs in the fridge - the longer they're kept inside, the less fresh they are.
This isn't to say at 30 your eggs aren't 'fresh', but egg quality starts to play a factor. Luckily, there are some lifestyle modifications you can adopt to help maintain egg quality - I'll be discussing that in a future post.
References
Obstetrics & Gynecology, 2019. ACOG Committee Opinion No. 773. 133(4), pp.e274-e278.