‘Unexplained’ Infertility Often Means Unexamined: The Tests Worth Asking About
Being told you have unexplained or idiopathic infertility is one of the most frustrating diagnoses a person can receive. In clinic, I often meet patients who have spent months, and sometimes years, being told that everything looks normal, yet they're still not pregnant. While unexplained infertility is a legitimate diagnosis, I find that in many cases only a standard workup has been completed before this diagnosis is given.
In many of my patients, there are still important pieces of the puzzle that simply haven't been investigated. Let's discuss three conditions that could be playing a role in unexplained infertility and are worth asking about.
Hashimoto's Thyroiditis
Most fertility clinics screen thyroid function early on with TSH testing and treat if hypothyroidism is found. What is commonly missed, however, is screening for autoimmune thyroid disease, also known as Hashimoto's thyroiditis.
Hashimoto's is a condition in which the immune system produces antibodies that can damage the thyroid gland. It is estimated to affect up to 20% of women of childbearing age, making it far more common than most people realize.
Research has found that the elevated thyroid antibodies seen in Hashimoto's can interfere with developing eggs and follicle quality, and women with Hashimoto's have been found to have lower AMH levels, a marker of egg reserve, compared to women without the condition. Higher miscarriage risk has also been associated with Hashimoto's thyroiditis.
One of the things that often surprises my patients is that they can have completely normal thyroid hormone levels and still test positive for Hashimoto's. Additionally, Hashimoto's often presents without any symptoms, which is another reason it is frequently missed. If your thyroid function has been tested and is normal, it is still worth considering this screening. Testing simply involves adding anti-TPO and anti-TG antibodies to a standard thyroid panel.
Celiac Disease
Celiac disease is another autoimmune condition in which the immune system reacts to gluten, causing damage to the small intestine. While commonly thought of as a digestive condition, it has meaningful implications for reproductive health. Research suggests up to 70% of celiac cases go undiagnosed because they present without any gastrointestinal symptoms, a presentation known as silent celiac disease.
Undiagnosed celiac disease is associated with difficulty conceiving and increased miscarriage risk, driven by nutrient deficiencies, chronic inflammation, and antibodies that impair uterine lining function in early pregnancy. The encouraging finding is that these risks are significantly reduced with diagnosis and a gluten-free diet.
Classic signs to look out for include bloating, abdominal pain, or changes in bowel habits, but because so many cases are silent, I consider celiac screening in unexplained infertility even when digestive symptoms are absent, particularly if iron is chronically low despite supplementation or there is a family history of the condition. Screening involves a simple blood panel that can be added to routine lab work.
Endometriosis
Endometriosis is a condition in which tissue similar to the uterine lining grows outside the uterus. It is found in an estimated 25 to 50% of women with infertility, yet diagnosis is delayed by five to twelve years on average. Classic signs include chronic period pain, pain with intercourse, and digestive symptoms, but silent endometriosis is a well-documented condition, and the absence of pain does not rule it out.
Endometriosis creates an inflammatory environment that can reduce egg quality, impair fertilization, and affect the uterine lining's ability to support implantation.
Endometriosis is one of the conditions I think about most often in cases of unexplained infertility because it is so prevalent and can be present even when symptoms are mild or absent.
An initial screening tool that can be considered is testing a marker called CA125 during a period. An elevated result increases suspicion and supports referral for further assessment through specialized imaging which is needed for a diagnosis.
Proper imaging requires an ultrasound performed by a sonographer trained specifically in endometriosis, as a routine pelvic ultrasound is not equivalent. If specialized ultrasound is clear but suspicion remains, a laparoscopy may be warranted.
Advocating for Yourself
An unexplained infertility diagnosis often deserves more questions and a deeper investigation. Some of the most meaningful answers I've uncovered with patients have come after they were told that everything had already been checked. While not every case will reveal a clear explanation, it is entirely reasonable to ask whether a more comprehensive workup has been done and to seek out a provider willing to look deeper. You deserve answers, and in many cases, they are there to be found.
Looking for more fertility support?
Understanding how to optimize your fertility, reduce miscarriage risk, and support yourself for the healthiest pregnancy possible is incredibly important. Naturopathic medicine offers many tools that can support you along your fertility journey. If you're looking for more guidance, in-depth testing, and a personalized approach to optimizing fertility, you can book an appointment with me here.
Frequently Asked Questions About Unexplained Infertility
What does unexplained infertility mean?
Unexplained infertility generally means that standard fertility testing has not identified a clear reason for difficulty conceiving. It does not necessarily mean that there are no contributing factors, and in some cases further investigation may be appropriate.
What tests are typically done for unexplained infertility?
A standard fertility assessment may include hormone testing, assessment of ovarian reserve and ovulation, imaging of the uterus and fallopian tubes, and semen analysis when applicable. Additional testing may be considered based on your health history, symptoms, and previous results.
Can thyroid issues affect fertility even if my TSH is normal?
It is possible to have normal thyroid hormone levels while also having thyroid antibodies associated with autoimmune thyroid disease. Whether additional thyroid testing is appropriate depends on your individual history and should be discussed with your healthcare provider.
Can endometriosis cause infertility without symptoms?
Yes. Some people with endometriosis have few or no obvious symptoms. If endometriosis is suspected despite a lack of significant pain, further assessment or specialized imaging may be considered.
Should I be tested for celiac disease if I'm having difficulty conceiving?
Celiac disease can sometimes occur without obvious digestive symptoms. Screening may be worth discussing with your healthcare provider, particularly when there are other risk factors or signs such as persistent iron deficiency or a family history of celiac disease.