Infertility is clinically defined as not being able to get pregnant after one year of regular, unprotected sex, or after six months if you’re over 35. That timeline is the standard starting point, but there are earlier signs your body may give you that something could be affecting your fertility, even before you start trying.
The Clinical Timeline
The one-year and six-month benchmarks exist because conception takes time even when everything is working perfectly. A healthy couple in their 20s or early 30s has roughly a 20 to 25 percent chance of conceiving in any given cycle. So not getting pregnant in the first few months is completely normal. The clock starts when couples begin having regular unprotected intercourse, not from a particular birthday or life milestone.
The shorter window for people over 35 reflects the natural decline in egg quantity and quality that accelerates in the mid-30s. If you’re in that age group and haven’t conceived after six months, seeking evaluation sooner rather than later gives you more options.
Menstrual Clues in Women
Your period is one of the most visible indicators of your reproductive health. Irregular cycles, where you regularly go three or four months without a period, or cycles that are unpredictable in timing, can signal that ovulation isn’t happening consistently. Without ovulation, conception isn’t possible.
Several conditions disrupt ovulation. Polycystic ovary syndrome (PCOS) is one of the most common. It’s diagnosed when you have at least two of the following: signs of elevated testosterone (excess facial or body hair, thinning hair on the scalp, acne or oily skin), irregular or absent periods, and polycystic ovaries visible on ultrasound. PCOS disrupts the normal release of eggs from the ovaries, and it often shows up as intermittent, unpredictable, or absent periods alongside skin and hair changes. Many people with PCOS also experience heavy or painful periods when they do occur.
Thyroid problems can also affect your cycle. Both an overactive and underactive thyroid interfere with menstrual regularity and ovulation. Another hormonal condition, where the body produces too much of the hormone prolactin, can suppress ovulation as well. Excessive exercise, eating disorders, and significant weight changes are additional causes of missed or irregular periods that can affect fertility.
Primary ovarian insufficiency, the loss of normal ovarian function before age 40, is a less common but more serious cause. People with this condition may have irregular or occasional periods for years before the issue is identified.
That said, irregular periods don’t automatically mean infertility. Some people with unpredictable cycles still ovulate, just not on a textbook schedule. The irregularity is a reason to investigate, not a diagnosis by itself.
Physical Signs in Men
Male infertility is responsible for roughly a third of all infertility cases, yet it often gets overlooked. Unlike menstrual irregularities, the signs tend to be subtler, but there are things to watch for.
Problems with sexual function are among the most noticeable: difficulty maintaining an erection, trouble with ejaculation, noticeably small volumes of fluid during ejaculation, or reduced sex drive. Pain, swelling, or a lump in the testicle area is another signal worth getting checked. Decreased facial or body hair, or unexpected breast tissue growth, can point to a hormonal or chromosomal issue affecting sperm production.
A less obvious sign is recurrent respiratory infections, which can indicate a rare genetic condition that also affects fertility. An inability to smell is associated with the same type of condition. These symptoms alone don’t confirm infertility, but combined with difficulty conceiving, they’re worth bringing up with a doctor.
What Fertility Testing Looks Like
For women, a fertility evaluation typically starts with blood tests to check hormone levels. Two key markers are AMH (anti-Mullerian hormone), which reflects the remaining egg supply, and FSH (follicle-stimulating hormone), which helps gauge how hard the body is working to stimulate the ovaries. Doctors may also use ultrasound to count the small fluid-filled sacs in the ovaries where eggs develop.
An important nuance with these tests: they measure ovarian reserve, not your ability to get pregnant. A large study of women aged 30 to 44 with no known fertility problems found that those with low AMH levels or elevated FSH had similar pregnancy rates over 6 and 12 months of trying compared to women with normal levels. So a “low” result on one of these tests doesn’t mean you can’t conceive naturally. What these markers are best at is predicting how you’d respond to fertility treatments like IVF, where egg quantity matters more.
For men, the standard test is a semen analysis, which measures sperm count (normal is 15 million or more per milliliter), the percentage of sperm that are moving, their shape, and the volume and acidity of the semen. A single low result doesn’t necessarily mean there’s a permanent problem, since sperm production fluctuates, so the test is often repeated.
What At-Home Tests Can and Can’t Tell You
At-home fertility tests have become widely available, but their usefulness has limits. For men, at-home sperm tests range from basic kits that simply confirm whether sperm is present to phone-based devices that estimate sperm concentration and motility. What they can’t do is assess sperm shape, the percentage of healthy sperm, semen volume, or acidity. A clinical semen analysis evaluates all of these. An at-home test might catch an obviously low count, but a normal-looking result doesn’t rule out problems that only a full lab analysis would find.
For women, at-home hormone tests typically measure hormones like FSH or AMH from a finger-prick blood sample. These can give you a snapshot of your ovarian reserve, but as noted above, those numbers don’t straightforwardly predict whether you’ll get pregnant. They also can’t detect structural issues like blocked fallopian tubes or endometrial tissue growing outside the uterus, both of which are common causes of infertility that require imaging or a physical exam to identify.
At-home tests are reasonable as a first step if you’re curious, but they’re not a substitute for a clinical workup if you’re actively struggling to conceive.
Signs That Warrant Earlier Testing
You don’t need to wait the full year (or six months) if you already have reasons to suspect a problem. Consider getting evaluated sooner if you experience any of the following: periods that are consistently absent or very irregular, very painful periods that interfere with daily life, a known history of pelvic infections or sexually transmitted infections, two or more miscarriages, prior cancer treatment, or a partner with known reproductive health issues.
For men, a history of testicular injury, undescended testicles, or groin surgery is also reason to check in earlier. The same goes for anyone taking medications that can affect hormone levels or sperm production, including testosterone supplements, which paradoxically reduce sperm count in many men.
Infertility is common, affecting an estimated one in six couples at some point. Having risk factors or even abnormal test results doesn’t mean pregnancy is impossible. It means there’s something specific to investigate, and in many cases, to treat.