The clearest sign of infertility is not getting pregnant after 12 months of regular, unprotected sex. If you’re over 35, that window shortens to 6 months. If you’re over 40, most experts recommend starting a fertility evaluation right away rather than waiting. Beyond that timeline, there are physical signs in both men and women that can signal a problem before you ever start trying.
About one in six people of reproductive age worldwide experience infertility at some point. It affects men and women roughly equally, and in many cases there are no obvious symptoms at all until a couple has trouble conceiving.
Signs in Women
The most telling clue is your menstrual cycle. A cycle shorter than 21 days, longer than 35 days, or one that’s highly irregular or absent altogether can mean you’re not ovulating. Without ovulation, pregnancy isn’t possible. Some women have always had irregular periods and assume it’s just how their body works, but that pattern is worth investigating if you’re planning to conceive.
Painful periods are another signal, particularly pain that goes beyond normal cramping. If your cramps cause you to miss work or school, or if you have pain during sex, during bowel movements, or in your lower back around your period, that pattern may point to endometriosis. Up to half of people with endometriosis have difficulty conceiving. The condition can block fallopian tubes and prevent an egg and sperm from meeting. Many people don’t find out they have it until they struggle to get pregnant.
Polycystic ovary syndrome (PCOS) is another common cause. It disrupts ovulation through a hormone imbalance and is often accompanied by acne, unusual hair growth on the face or body, weight gain, and insulin resistance. Irregular or absent periods are its most recognizable feature.
Beyond these conditions, many women with fertility issues have no symptoms at all. That’s what makes it tricky. A perfectly regular cycle doesn’t guarantee everything is working, and an irregular one doesn’t automatically mean you can’t conceive.
Signs in Men
Male infertility is even less visible. Most men have no idea there’s a problem until a couple has been trying without success. But there are a few physical signs worth knowing about.
Changes in sexual function can be a red flag: difficulty maintaining an erection, trouble with ejaculation, noticeably low ejaculate volume, or a significant drop in sex drive. Pain, swelling, or a lump in the testicle area also warrants attention.
Hormonal issues sometimes show up physically. Decreased facial or body hair, or unusual breast tissue growth, can indicate a hormonal or chromosomal abnormality that affects sperm production. A low sperm count (fewer than 15 million sperm per milliliter of semen) is one of the most common male fertility issues, but you’d only discover that through testing.
How Age Affects Fertility
Age plays a significant role, especially for women. In your early to mid-20s, the chance of getting pregnant in any given month is about 25 to 30 percent. By age 40, that drops to around 5 percent per cycle. That steep decline is why the recommended evaluation timeline is shorter for older women: 6 months of trying at 35 and older, and immediate evaluation at 40.
Men’s fertility also declines with age, though more gradually. Sperm quality, motility, and volume all decrease over time, and the risk of genetic abnormalities in sperm increases. Age alone doesn’t mean you’re infertile, but it narrows the window and makes early evaluation more important.
What a Fertility Evaluation Looks Like
If you suspect something is off, or you’ve been trying long enough to meet the timeline thresholds, a fertility evaluation typically starts with your OB-GYN or primary care doctor. For women, this usually involves blood tests to check hormone levels related to ovulation, an ultrasound to look at the ovaries and uterus, and sometimes an imaging procedure to check whether the fallopian tubes are open. For men, the first step is almost always a semen analysis, which measures sperm count, movement, and shape.
These initial tests can identify the most common problems. If they reveal something more complex, or if results come back normal but pregnancy still isn’t happening, you may be referred to a reproductive endocrinologist for more specialized testing and treatment options.
When to Act Sooner
Some situations call for earlier evaluation, even if you haven’t been trying for a full year. If you have a history of irregular or painful periods, known endometriosis or PCOS, prior pelvic surgery, or a history of sexually transmitted infections, those factors increase the chance that something may need attention. The same goes for men who’ve had testicular injuries, surgeries, or known hormone issues.
Infertility doesn’t always announce itself with obvious symptoms. For many couples, the only sign is time passing without a positive pregnancy test. If that’s where you are, the evaluation itself is straightforward, and knowing sooner gives you more options.