If you have been trying to conceive for 12 months (or 6 months if you are over 35) without success, you are not alone. Approximately 1 in 6 couples worldwide experience fertility delays. While the process can feel isolating and deeply personal, understanding the underlying causes is the first and most powerful step toward finding a pathway forward.
Here are the four key categories of fertility delays, broken down by which partner the cause is typically attributed to.
When is Infertility?
Medically, infertility is defined as the inability to conceive after 12 months of frequent, unprotected intercourse. However, we prefer the term “Fertility Delay” here.
Key 1: Female Factor Causes (Approx. 40%)
When a delay is attributed to the female partner, the causes almost always fall into one of two areas: Ovulation or Plumbing.
A. Ovulatory Dysfunction (Egg Release)
This is the most common cause of female fertility delays. If an egg is not released regularly, conception cannot occur.
- PCOS (Polycystic Ovary Syndrome): This hormonal imbalance interferes with the signals needed to mature and release an egg. It is characterized by irregular or absent periods.
- Primary Ovarian Insufficiency (POI): This occurs when the ovaries cease to function normally before age 40, resulting in reduced egg production and irregular cycles.
- Thyroid Dysfunction: Both an overactive and an underactive thyroid can interfere with ovulation and hormonal balance, making regular conception difficult.
B. Tubal or Uterine Factors (Plumbing)
These issues prevent sperm from reaching the egg or prevent the successful implantation of the embryo.
- Blocked Fallopian Tubes: Often caused by previous pelvic infections, Endometriosis, or scar tissue, blockages prevent the egg from traveling to the uterus or the sperm from reaching the egg.
- Endometriosis: This condition, in which tissue similar to the uterine lining grows outside the uterus, can cause inflammation and scarring that damage the fallopian tubes or ovaries.
- Uterine Issues: Fibroids, polyps, or anatomical abnormalities inside the uterus can interfere with implantation.
Key 2: Male Factor Causes (Approx. 40%)
The male partner is solely or partially responsible for fertility delays in approximately 40% of cases. The issue is almost always related to Sperm Quality, Quantity, or Delivery.
A. Sperm Production and Health
- Low Sperm Count (Oligospermia): Fewer sperm are available to make the journey.
- Poor Sperm Motility: Sperm are produced but cannot swim effectively to reach the egg.
- Abnormal Sperm Morphology: The sperm’s shape is abnormal, making fertilization difficult.
The Nest Insight: Sperm health can be dramatically affected by lifestyle factors such as heat (saunas, tight clothing), heavy drinking, smoking, and environmental toxins. These factors can often be reversed with targeted changes.
B. Delivery Issues
Blockages in the tubes that carry sperm or issues with ejaculation can prevent healthy sperm from reaching the female reproductive tract.
Key 3: Combined and Unexplained Causes (Approx. 20%)
A. Combined Factor
In some cases, both partners have minor issues that, when added together, create a significant fertility delay—for instance, low-average sperm count combined with infrequent ovulation.
B. Unexplained Infertility (UI)
This diagnosis is made when all standard testing for both partners (ovulation tracking, hormone levels, sperm analysis, and tubal patency) is normal.
The Nest Insight: This diagnosis can be particularly frustrating, but it indicates that there is no clear structural or hormonal barrier. UI often prompts providers to consider subtle factors, such as inflammation, immune responses, or lifestyle issues, that standard tests may miss. It still has effective treatment pathways. (Source: American Society for Reproductive Medicine, ASRM).
Finding Hope: Your Next Step
The statistics surrounding fertility can be hard to hear, but remember the power word: Hope. A diagnosis of a fertility delay is not a roadblock; it is simply a map. It points you and your doctor toward a specific area of intervention.
If you are concerned about delays, your next step is to schedule an appointment with a reproductive endocrinologist or another specialist to test both partners.
