Infertility is defined as not achieving pregnancy after 12 months of regular, unprotected sex. If you’re over 35, that timeline shortens to 6 months, and if you’re over 40, it’s worth getting evaluated right away rather than waiting. That timeline is the single most important indicator, but there are earlier signs in both men and women that can signal a problem before you ever start trying.
The Timeline Is the Primary Indicator
Most couples who are going to conceive naturally will do so within the first year of trying. That 12-month mark isn’t arbitrary. It’s the threshold that reproductive medicine organizations worldwide use to define infertility as a medical condition. About 85% of couples conceive within that window, so not getting pregnant after a full year of well-timed, unprotected intercourse is itself the clearest sign something may need investigation.
Age changes the math significantly. Fertility declines with age in both men and women, but the effect is more pronounced and better documented in women. If you’re 35 or older, the recommendation is to seek evaluation after just 6 months of trying. If you’re over 40, don’t wait at all. Talk to your doctor before you start trying or as soon as you decide you want to conceive.
Signs in Women That Suggest a Problem
Many women with fertility issues have no obvious symptoms at all. The inability to get pregnant is often the only sign. That said, certain menstrual patterns can hint at ovulation problems, which account for a large share of female infertility.
Pay attention to your cycle length and regularity. A cycle shorter than 21 days, longer than 35 days, or one that varies wildly from month to month can mean you’re not ovulating consistently. Absent periods are an even stronger signal. Extremely heavy or painful periods may point to conditions like endometriosis or uterine fibroids, both of which can interfere with conception.
A history of pelvic inflammatory disease, repeated miscarriages (two or more), or prior cancer treatment are also red flags that warrant earlier evaluation, regardless of how long you’ve been trying.
Signs in Men That Suggest a Problem
Male factors contribute to roughly half of all infertility cases, yet men often assume the issue lies elsewhere. Several physical signs can point to a problem:
- Changes in sexual function: difficulty maintaining an erection, reduced sex drive, or problems with ejaculation, including very low ejaculate volume.
- Testicular changes: pain, swelling, or a noticeable lump in the testicle area. Small or soft testicles can also indicate low sperm production.
- Unusual breast growth: enlarged breast tissue in men can signal a hormonal imbalance affecting sperm production.
- Decreased body or facial hair: this can indicate a chromosomal or hormonal issue.
One common and often overlooked condition is a varicocele, which is a swelling of the veins that drain the testicle. Varicoceles are usually painless and feel like a soft lump above the testicle, sometimes described as a “bag of worms.” They’re detectable through a physical exam, often while standing and bearing down. A doctor may also use ultrasound to confirm the diagnosis. Varicoceles can raise the temperature around the testicle and impair sperm quality.
Another condition that’s hard to detect on your own is retrograde ejaculation, where semen travels backward into the bladder during orgasm instead of exiting the body. If you notice cloudy urine after sex or very little fluid when you ejaculate, this could be a factor.
What Fertility Testing Looks Like
If you suspect a problem, testing typically starts simple and becomes more involved only if needed.
For women, the first step is usually blood work timed to specific days of the menstrual cycle. Doctors check hormones that reflect ovarian function. One key hormone, FSH (follicle-stimulating hormone), gives a rough gauge of how many eggs remain. Levels under 6 are considered excellent, 6 to 9 good, and anything above 10 suggests a diminished supply. High estrogen levels early in the cycle can also point to reduced ovarian reserve. When the ratio of two hormones (LH and FSH) is skewed, it can be one indicator of polycystic ovary syndrome (PCOS), a common cause of irregular ovulation. Anti-Mullerian hormone (AMH) is another blood test now widely used as an alternative measure of egg supply.
Beyond blood work, doctors often want to check whether the fallopian tubes are open and the uterus is structurally normal. The most common test for this is an HSG, where a contrast dye is injected through the cervix while X-ray images are taken. If the tubes are open, the dye flows through and spills out the ends. Blockages or abnormalities inside the uterus show up as disruptions in the dye’s path. An alternative uses saline and air bubbles viewed on ultrasound, though it’s considered less reliable for evaluating the tubes.
For men, a semen analysis is the cornerstone test. A lab evaluates sperm concentration (normal is 15 million or more per milliliter), motility (how many are actually swimming), morphology (shape and size), ejaculate volume, and pH. You could have a high sperm count but still face fertility issues if none of the sperm are moving normally. Only a full lab analysis can reveal the complete picture.
Why At-Home Tests Fall Short
At-home sperm tests and ovulation kits are widely available and can provide some useful data, but they have real limitations. Most at-home sperm tests only measure whether sperm are present or report a basic concentration number. Some newer kits attach to a smartphone to estimate motility. But none of them assess morphology, vitality, volume, or pH, all of which matter for fertility.
The issue isn’t necessarily accuracy for what they measure. It’s that they only measure a fraction of what a lab does. You could get a “normal” result on a home test and still have a significant fertility problem that only a full semen analysis would reveal. A man with 100 million sperm per sample, for example, would test as perfectly normal on most home kits, but if none of those sperm are moving, conception won’t happen naturally.
Ovulation predictor kits, which detect the hormone surge before ovulation, are more useful as a timing tool than as a diagnostic one. They can confirm that a surge is happening, but they can’t tell you whether you’re actually releasing an egg or whether the egg is viable.
Conditions That Commonly Cause Infertility
In women, the most frequent culprits are ovulation disorders, blocked or damaged fallopian tubes, and endometriosis. PCOS is the leading cause of ovulation-related infertility. It’s now diagnosed using an evidence-based approach that looks at irregular cycles, signs of excess androgens (like acne or excess hair growth), and either ultrasound findings or elevated AMH levels. You generally need two of these three criteria for a diagnosis.
In men, the causes tend to cluster around sperm production and delivery. Varicoceles, hormonal imbalances, genetic conditions, prior infections, and certain medications can all reduce sperm count or quality. Lifestyle factors like heavy alcohol use, tobacco, anabolic steroids, and prolonged heat exposure (such as frequent hot tub use) are also well-established contributors.
In about 15% to 30% of cases, no clear cause is found in either partner. This is called unexplained infertility, and while it’s frustrating, it doesn’t mean treatment can’t help. It simply means the standard tests haven’t identified a specific barrier.
Tracking Your Own Fertility at Home
Before you see a doctor, there are a few things worth tracking that can speed up the diagnostic process. For women, keeping a record of cycle length and regularity for three to four months gives your doctor immediate, useful data. Noting any mid-cycle changes in cervical mucus (it typically becomes clear and stretchy around ovulation) and using basal body temperature tracking can help confirm whether ovulation is occurring. A slight temperature rise of about half a degree after ovulation, sustained for at least 10 days, is a good sign.
For men, paying attention to any changes in ejaculate volume, sexual function, or testicular discomfort is worth noting. These details help a doctor decide which tests to prioritize. Both partners should expect to be evaluated. Infertility is roughly equally split between male and female factors, and in many cases, mild issues on both sides combine to create the problem.