Explaining Unexplained Infertility

February 1, 2024
In vitro fertilization (IVF)

Many couples suffer from fertility issues. Fertility issues do not come to light until you actively start trying to start a family. The issue could be with the male, the female, both or neither. Yes, there are cases where all reports will be clear, and the doctor will give a clean chit of fertility, but the couple will still have difficulty conceiving. When and why does this happen? Come, let’s learn more about unexplained fertility.

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What is Infertility?

Infertility is a condition where a couple, despite trying hard for a year, is unable to conceive. The couple are unable to get pregnant and the reasons could be plenty. It could be some underlying health issue with one or both partners, issues with the reproductive organs, etc. It is quite difficult to identify the exact cause of infertility as there could always be more than just one.

Reasons for Infertility

The reasons for infertility could be plenty. If you and your partner have been trying for a year and have not conceived, you need to consult a fertility specialist. The doctor will test both partners to identify the possible causes of infertility.

The tests can reveal issues with one or both partners. Many couples go on to successfully conceive despite various fertility issues. They either conceive naturally after treatments or undergo fertility procedures like IUI or IVF.

Some of the common causes of infertility in a couple are:

  • Age of the partners – the age of both partners matters. The higher the age, the lower the chances of pregnancy
  • Irregular, painful, or lack of periods in the woman
  • Tests reveal issues with the egg, sperm, or both
  • Other underlying health conditions
  • Pelvic infections and inflammatory diseases
  • Cancer or cancer treatment like chemotherapy or radiation

What is Unexplained Infertility?

Sometimes, all tests will come back clear and there will be no proper explanation for a couple’s infertility. When the fertility tests reveal no obvious cause for infertility, the doctor will term it as unexplained infertility

This usually happens when both partners are not too old, the woman has regular periods, the fallopian tube is open and has no blocks, the sperm and egg health are good, the egg reserve is good and the hormonal production in both partners is also good.

When a couple has been trying to get pregnant for over a year, has undergone all fertility tests and the results are all clear, they suffer from unexplained infertility. There is no obvious cause for their infertility.

Is Unexplained Infertility Common?

The exact rates of unexplained infertility are still unknown. The understanding of fertility differs from couple to couple and even from doctor to doctor. While some couples seek medical help when they are unable to conceive, some just keep trying and eventually give up or accept the infertility without getting it checked.

So, it is quite difficult to diagnose unexplained infertility in couples. 

Unexplained Infertility Reasons

Unexplained infertility is a condition where the doctor is unable to explain the exact reason for infertility in a couple. The reason for such a condition could be:

  1. Undiagnosed Health Condition – Many health issues can negatively impact your fertility. It is difficult to identify which health issues can impact your fertility. So, if one or both partners have some undiagnosed health condition, it could be affecting their fertility, without their knowledge.
  2. Endometriosis – In some cases, endometriosis can affect the way the fallopian tubes, ovaries, and uterus work. Many women ignore endometriosis pain as regular menstrual cramps. This can, in turn, affect your chances of pregnancy.  
  3. Cervical Mucus – The cervical mucus acts as a medium that helps the sperm slip inside and travel up to the egg during ovulation. If the cervical mucus is not in the right consistency or is too thick, it can prevent the sperm from swimming up to meet the egg, thus preventing conception.
  4. Egg QualityIf the egg is not of great quality, it may not lead to a successful conception. Despite the sperm meeting the egg, the egg may not fertilize or attach properly. As a result, pregnancy may not happen.
  5. Sperm Quality – Poor sperm quality could be low sperm count or low sperm motility. Sometimes, the tests can show everything is good with the sperm quality but it could have other issues that might be preventing the male from impregnating his partner. Unless specific advanced sperm function tests are conducted on the sperm, it cannot be identified.
  6. Endometrial  Lining – the endometrium lining starts thickening as the egg grows and it is maximum at the time of ovulation. The embryo will attach to this lining and stay attached until it is time for the delivery. If the endometrium lining is not thick or ready enough for the embryo to attach, it can lead to a miscarriage.
  7. Wrong Timing – Sometimes, the issue could be as simple as poor timing, you could be calculating the dates wrong and missing your ovulation window. Ovulation is the peak fertile window for a woman and having sex after ovulation could be too late. The egg would already be descending the fallopian tube and the sperm may not meet it in time. So, despite tracking dates and having unprotected sex, you could be just missing the right time to conceive.

Unexplained Infertility Diagnosis

Diagnosing unexplained infertility can be very difficult. Since all the basic  fertility tests will come back clear, it can be quite difficult to diagnose unexplained infertility. If the doctors are unable to identify a cause for your infertility, they may try various methods and encourage you to continue trying for a few more months. If you are unable to conceive despite the guided efforts, then they will confirm the diagnosis.

Unexplained Infertility Treatment

Since all tests come back clear and there is no reason for infertility, there is no treatment for unexplained infertility. In case of unexplained infertility, the doctor will give you general guidelines to follow. Some of these include – 

  • Maintaining a healthy weight
  • Quitting various substances and adopting a healthy lifestyle
  • Tracking dates and having sex on specific dates
  • Treating underlying health conditions that could be interfering with your fertility- such as thyroid / high blood sugar issues.
  • Medications to increase the monthly egg release, to increase the chances of conception
  • IUI or IVF treatments


Unexplained infertility is more common than you would think. Many couples suffering from infertility have clean test results, leading to a diagnosis of unexplained infertility. If you and your partner are struggling to conceive, consult a gynecologist to understand the various causes of unexplained infertility. Many couples go on to have successful pregnancies with the right help and so can you.


1. What are the criteria for unexplained infertility?

When a couple is unable to conceive despite trying for a full year and undergoes various fertility tests, which show no issues, the doctor will diagnose their condition as unexplained infertility. 

2. What is the medical term for unexplained infertility?

The medical term for unexplained infertility is “idiopathic infertility”. It means there is no evident cause for infertility. According to all fertility tests, both partners have no fertility issues. 

3. Can I get pregnant naturally with unexplained infertility?

Yes, many couples get pregnant naturally despite unexplained infertility. Since the exact reasons for unexplained infertility are unknown, it is difficult to predict when the problem will be resolved. However, there are chances for natural conception. s

4. What tests can be done for unexplained infertility?

Regular fertility tests can be done to check if everything is okay. Your fertility doctor might also check your reproductive organs and tracts for other issues that could be impacting your fertility.