You can’t know for certain whether you’re infertile without medical testing, but there are specific timelines, body signals, and screening tools that can tell you whether it’s time to find out. The standard benchmark: if you’ve been having regular unprotected sex for 12 months without conceiving, that meets the clinical definition of infertility. If you’re over 35, that window shortens to 6 months. If you’re over 40, getting evaluated now, before months of trying, is the recommended approach.
Infertility affects both men and women roughly equally, and in many cases there are no obvious symptoms at all. But your body does offer clues worth paying attention to, and the diagnostic process is more straightforward than most people expect.
Signs That May Point to Female Infertility
Your menstrual cycle is one of the most accessible indicators of your reproductive health. A cycle shorter than 21 days, longer than 35 days, or one that’s unpredictable from month to month can signal that you’re not ovulating regularly. Absent periods are an even stronger red flag. In some cases, irregular or missing periods are the only outward sign of a fertility problem.
Polycystic ovary syndrome (PCOS) is one of the most common hormonal causes of infertility. It’s diagnosed when at least two of the following are present: signs of elevated testosterone (excess facial or body hair, hair thinning on the scalp, acne or oily skin), irregular or absent periods, and ovaries that appear polycystic on ultrasound. PCOS disrupts ovulation and is also linked to insulin resistance and weight gain. Some women with PCOS have regular cycles but still aren’t ovulating normally, which is why blood tests checking hormone levels can be useful even when periods seem fine.
Endometriosis, a condition where tissue similar to the uterine lining grows outside the uterus, is another significant contributor. Severe menstrual pain, pain during sex, and heavy periods can all be signs, though some women with endometriosis experience no symptoms at all.
Signs That May Point to Male Infertility
Male infertility is trickier to spot because the primary sign is simply not being able to conceive. Most men have no obvious symptoms. When clues do exist, they tend to fall into a few categories.
Changes in sexual function are worth noting: difficulty with ejaculation, noticeably low volumes of ejaculate, reduced sex drive, or trouble maintaining an erection. Physical changes matter too. Pain, swelling, or a lump in the testicle area warrants attention, as does one testicle being noticeably smaller than the other. Less intuitive signs include decreased facial or body hair, unusual breast tissue growth, and even recurrent respiratory infections or an inability to smell, which can indicate rare genetic conditions that affect both fertility and other body systems.
Varicoceles, which are enlarged veins in the scrotum, are found in about 40% of men with fertility problems. They often cause no pain, though some men notice a dull ache that worsens throughout the day and improves when lying down. A larger varicocele can feel like a soft mass above the testicle. Not all varicoceles cause infertility (only 10% to 20% of men diagnosed with one have trouble conceiving), but they’re one of the more treatable causes.
What You Can Check at Home
Ovulation predictor kits, available at any pharmacy, detect the hormone surge that happens one to two days before you ovulate. A 2024 study comparing five popular brands found that all of them had specificity above 97% when measured against blood hormone levels, meaning they’re very reliable at confirming you haven’t surged yet. Sensitivity (catching the actual surge) varied more, ranging from about 38% to 77% depending on the brand, with Easy@Home and Pregmate performing best. Using these kits over a few cycles can help you determine whether you’re ovulating at all and whether your timing is right.
Tracking your basal body temperature each morning and monitoring cervical mucus changes are free, low-tech alternatives that can reveal ovulation patterns over time. These methods require consistency but can give you useful data to bring to a doctor if you do seek help.
Home sperm test kits exist, but they only measure sperm concentration. They can’t assess motility (how well sperm swim) or morphology (their shape), both of which matter for fertility. A home kit showing a “normal” count doesn’t rule out a problem, so treat these as a rough first screen rather than a definitive answer.
How Doctors Test Female Fertility
A fertility evaluation typically starts with blood work timed to specific days of your cycle. On day 3, your doctor will likely check two key hormones. Follicle-stimulating hormone (FSH) indicates your ovarian reserve, essentially how your egg supply is holding up. Levels under 6 are considered excellent, 6 to 9 good, 9 to 10 fair, and above 10 suggest a diminished reserve. Luteinizing hormone (LH) is checked at the same time; when LH is higher than FSH, it’s one indicator of PCOS.
Beyond blood work, imaging helps identify structural issues. A hysterosalpingogram (HSG) is a specialized X-ray where dye is passed through the uterus and fallopian tubes. It shows whether the tubes are partially or fully blocked and whether the uterus has an abnormal shape or scarring, both of which can prevent pregnancy. Ultrasound-based alternatives exist too: one version uses saline solution to get a clearer picture of the uterine lining and track whether fluid flows freely through the fallopian tubes.
A transvaginal ultrasound can also check for ovarian cysts, fibroids, or structural abnormalities in the uterus. Your doctor may count the small follicles visible on your ovaries as another measure of ovarian reserve.
How Doctors Test Male Fertility
A semen analysis is the starting point. You’ll provide a sample, typically after two to five days of abstinence, and the lab evaluates sperm concentration, motility, and morphology. Interestingly, the latest edition of the World Health Organization’s laboratory manual has moved away from rigid “normal vs. abnormal” cutoffs, recognizing that fertility decisions are more complex than a single number. Your doctor will interpret your results in context rather than checking them against a strict threshold.
If the semen analysis shows potential issues, further testing might include hormone blood work (testosterone and FSH levels), a scrotal ultrasound to check for varicoceles or structural blockages, and in some cases genetic testing. A physical exam can also catch issues like varicoceles or absent vas deferens, the tubes that carry sperm.
Age and Fertility Timelines
Age is the single most significant factor in female fertility. Egg quantity and quality decline gradually through your 20s and 30s, then drop more sharply after 35. This is why the recommended evaluation timeline shifts with age: 12 months of trying if you’re under 35, 6 months if you’re 35 to 39, and an immediate conversation with your doctor if you’re 40 or older.
Male fertility also declines with age, though more gradually. Sperm quality, including motility and DNA integrity, tends to decrease after 40. Men don’t face the same sharp biological deadline, but age still matters, and a man in his 40s or beyond shouldn’t assume the issue lies entirely with his partner.
What Infertility Doesn’t Mean
An infertility diagnosis means you haven’t conceived within the expected timeframe. It doesn’t mean you can’t conceive at all. Roughly half of couples who seek treatment go on to have a baby. Many causes of infertility are treatable, from medication that restores ovulation to minor procedures that address structural blockages. Even unexplained infertility, where no clear cause is found, responds to treatment in many cases.
Both partners should be evaluated simultaneously. In about a third of cases the issue is with the woman, in about a third it’s with the man, and in the remaining third it’s a combination of both or unexplained. Skipping the male evaluation wastes time and money and is one of the most common missteps couples make early on.