Unexplained Infertility

Unexplained Infertility: Causes, Testing & Treatment

Unexplained infertility occurs when a couple has difficulty conceiving despite normal fertility test results. Around 10% of couples seeking fertility support receive this diagnosis.

While it can feel frustrating not to have a clear cause, it does not mean your situation is without hope. City Fertility’s specialists are skilled in identifying subtle factors that routine testing may miss and will work with you to explore evidence‑based treatment options tailored to your circumstances.

What is Unexplained Infertility?

Unexplained infertility is the term used when all standard fertility investigations return normal results, yet a couple has been unable to conceive after 12 months of trying. Both partners may have healthy hormone levels, normal anatomy, and no obvious reproductive conditions. This means routine testing has not been able to pinpoint a cause, though this does not rule out underlying issues. Unexplained fertility causes often relate to subtle problems with egg quality, sperm function, fertilisation, or the implantation process that fall below the threshold of what standard diagnostics can detect. While it can feel like an uncertain place to be, it is absolutely a starting point for effective treatment.

What Causes Unexplained Infertility?

While no single cause can be identified, several factors are known to contribute to unexplained infertility causes:

• Minor ovulation irregularities: Small disruptions in the timing or quality of ovulation that don’t show up on standard cycle tracking or hormone tests.
• Reduced egg quality: Eggs may appear structurally normal but carry subtle chromosomal issues that affect fertilisation or early embryo development.
• Sperm function problems: Male infertility factors such as DNA fragmentation or reduced sperm motility can be present even when a basic semen analysis looks normal.
• Implantation difficulties: A fertilised embryo may fail to implant successfully in the uterine lining despite both the embryo and uterus appearing healthy.
• Endometriosis: Mild or undetected endometriosis is a recognised contributor to female infertility that can go undiagnosed without more invasive investigation.
• Immune responses: In some cases, the immune system may interfere with fertilisation or implantation in ways that standard testing does not screen for.
• Hormonal imbalances: Minor fluctuations in reproductive hormones can affect reproductive health without triggering abnormal results on routine blood panels.

The encouraging news is that with thorough investigation, many contributing factors can be identified and a targeted treatment plan put in place. If you have been trying to conceive without success, book an appointment to get a consultation from City Fertility’s specialists today.

How is Unexplained Infertility Diagnosed?

A Diagnosis of Exclusion

Unexplained infertility is diagnosed only after comprehensive fertility testing and all results come back within normal range. Rather than identifying a specific condition, it is a diagnosis reached after ruling everything else out.

Common Fertility Tests

City Fertility’s specialists perform comprehensive fertility testing to ensure no contributing factor is overlooked. Core assessments include:

• Hormone testing: Measures key reproductive hormones including FSH, LH, oestrogen, progesterone, and AMH to assess ovarian function and overall hormonal balance.
• Ultrasound scans: Evaluates the uterus, ovaries, and antral follicle count to identify any structural concerns and support ovarian reserve assessment.
• Hysterosalpingogram (HSG): An imaging procedure that checks whether the fallopian tubes are open and the uterine cavity is normal.
• Semen analysis: Assesses sperm count, motility, and morphology to evaluate male reproductive health.
• Ovarian reserve testing: Combines AMH blood tests with antral follicle count to estimate remaining egg supply.

Every result informs the treatment pathway, helping City Fertility’s specialists build the most targeted plan for your situation.

Treatment Options for Unexplained Infertility

A diagnosis of unexplained infertility does not mean untreatable. Many couples conceive successfully with the right support and a well-structured treatment plan. Treatment for unexplained infertility depends on individual factors including age, how long you have been trying, and your broader medical history. City Fertility provides a personalised unexplained infertility treatment plan that may include fertility medication to support ovulation, intrauterine insemination (IUI), or in vitro fertilisation (IVF). IVF is particularly valuable in these cases, as the process itself can reveal how eggs and sperm interact, offering insights that no standard test can provide and helping to identify subtle causes that may have otherwise gone undetected. Where egg quality is a concern, donor egg IVF may also be explored as an option.

Lifestyle and Emotional Support

Dealing with unexplained infertility can be emotionally draining, particularly when there is no clear answer as to why conception hasn’t occurred. Managing stress, maintaining a balanced diet, staying physically active, and limiting alcohol and caffeine intake can all positively influence reproductive health and overall fertility outcomes.

Equally important is seeking emotional support. The psychological weight of fertility challenges is real, and it should not be carried alone. City Fertility provides dedicated fertility counselling to help patients navigate the emotional side of their journey, offering a safe space to process feelings and build resilience throughout treatment.

When to See a Fertility Specialist?

Knowing when to seek help is an important part of the process. As a general guide, couples under 35 who have been trying to conceive for 12 months without success should consult a fertility specialist. For those over 35, seeking advice after 6 months is recommended, as age can affect both egg quality and treatment options.

Early consultation gives specialists the best opportunity to uncover subtle contributing factors and explore the full range of options available to you. Meet the fertility specialists at City Fertility to find the right fit for your care.

Frequently Asked Questions