Infertility is clinically defined by time: if you’re under 35 and haven’t conceived after 12 months of regular, unprotected sex, or if you’re 35 to 40 and haven’t conceived after 6 months, that meets the medical threshold. If you’re over 40, doctors recommend an evaluation right away. But well before you hit those timelines, your body often gives signals that something may be off. Here’s what to watch for and what testing actually involves.
The Timeline That Defines Infertility
Fertility isn’t instant even when everything is working perfectly. A woman in her early to mid-20s has roughly a 25 to 30% chance of conceiving in any given month. By 40, that drops to about 5% per cycle. So not getting pregnant in the first few months doesn’t mean something is wrong.
The standard benchmarks exist because they account for these probabilities. Twelve months of trying gives a couple under 35 enough cycles that most fertile couples will have conceived. Six months is the cutoff for those 35 to 40 because egg quality and quantity decline faster in that window, and earlier intervention improves outcomes. Past 40, or if you have a known risk factor like endometriosis, a history of pelvic inflammatory disease, or a previous ectopic pregnancy, there’s no reason to wait at all.
Signs in Women That Suggest a Problem
The most telling signal is your menstrual cycle. A cycle shorter than 21 days, longer than 35 days, highly irregular, or completely absent often means you’re not ovulating consistently. No ovulation means no egg available for fertilization, regardless of anything else. Irregular or absent periods are the most common sign of a disruption in the hormonal chain that triggers ovulation.
Polycystic ovary syndrome (PCOS) is one of the most frequent causes. It creates a hormone imbalance that interferes with ovulation and is often accompanied by insulin resistance, weight gain, acne, and unusual hair growth on the face or body. If you recognize that cluster of symptoms alongside irregular periods, PCOS is worth investigating.
Endometriosis is another major contributor. Women with endometriosis typically experience chronic or cyclical pelvic pain, painful periods, and pain during sex. An ovarian cyst called an endometrioma can sometimes be seen on ultrasound, but smaller deposits of endometrial tissue outside the uterus often can’t be detected by imaging alone and may require surgery to confirm.
Other red flags include a history of sexually transmitted infections (which can scar or block the fallopian tubes), thyroid problems, repeated miscarriages, or prior cancer treatment. Any of these warrants earlier evaluation rather than waiting out the full 12 months.
Signs in Men That Suggest a Problem
Male factors contribute to roughly half of all infertility cases, yet many men assume the issue must be on their partner’s side. There are physical signs worth paying attention to. Difficulty maintaining an erection, problems with ejaculation, noticeably low ejaculate volume, or reduced sex drive can all point to hormonal or structural issues affecting sperm production or delivery.
Pain, swelling, or a lump in the testicle area is another warning sign and should be evaluated regardless of fertility concerns. Less obvious indicators include unusual breast tissue growth or a noticeable decrease in facial or body hair, both of which can signal a hormonal or chromosomal abnormality affecting sperm production.
What Fertility Testing Looks Like
The first visit with a fertility specialist is mostly a conversation. You’ll be asked detailed questions about your menstrual cycle, any abnormal bleeding or discharge, pelvic pain, sexual history, and conditions that affect reproduction like thyroid disease. Both partners are typically evaluated at the same time, since pinpointing the cause early saves months of guesswork.
Hormone Testing
For women, one of the most informative blood tests measures anti-Müllerian hormone (AMH), which reflects your ovarian reserve, essentially how many eggs you have left. Average AMH levels fall between 1.0 and 3.0 ng/mL. Below 1.0 is considered low, and below 0.4 is severely low. These numbers naturally decline with age: a typical 30-year-old might have an AMH around 2.5, while a 40-year-old might be closer to 1.0. AMH can also run unusually high in women with PCOS. Results can vary slightly between labs, so your doctor will interpret them in context with your age and other findings.
Other hormonal tests check thyroid function and the pituitary hormones that regulate your cycle. For men, hormone testing can reveal low testosterone or other imbalances that reduce sperm production.
Structural Testing
A hysterosalpingogram (HSG) is a common imaging test for women. A contrast dye is injected into the uterus and fallopian tubes, then X-rays are taken to check for blockages in the tubes or irregularities in the shape of the uterus. Blocked or damaged tubes can result from past infections, endometriosis, or prior ectopic pregnancy. The test can also reveal fibroids, polyps, or structural variations in the uterus that may interfere with implantation.
Semen Analysis
For men, a lab-based semen analysis is the gold standard. A sample is evaluated under a microscope and by computer to measure exact sperm concentration, the percentage of sperm that are alive and healthy, how well they move, and their shape. This gives a comprehensive picture that no home test can match.
At-Home Fertility Tests: What They Can and Can’t Tell You
At-home sperm tests have been FDA-approved since 2012, and they range from basic kits that simply confirm sperm is present to smartphone-based devices that use your phone’s camera to estimate sperm concentration and movement. These aren’t inaccurate for what they measure. The problem is they don’t measure enough. A professional lab evaluates sperm health, shape, vitality, and other factors that home kits can’t assess. A home test might tell you your sperm count looks normal while missing a motility or morphology issue that’s preventing conception.
For women, at-home hormone kits can measure AMH or other markers from a finger-prick blood sample. These can offer a useful early snapshot, particularly if you’re not yet trying to conceive but want a sense of your ovarian reserve. But a single hormone reading can’t detect blocked tubes, endometriosis, or structural issues. Home testing is a starting point, not a substitute for clinical evaluation.
Lifestyle Factors That Affect Your Fertility
Some fertility factors are outside your control, like age and genetics. Others aren’t. Smoking is one of the most well-documented risks. A large analysis comparing nearly 11,000 women who smoked with over 19,000 who didn’t found that smokers were about 60% more likely to experience infertility. Smoking also appears to accelerate egg loss, with menopause arriving 1 to 4 years earlier in smokers on average. It increases miscarriage risk as well.
Body weight matters at both extremes. Women who are significantly underweight or obese have measurably reduced fertility rates, though moderate weight variations in women who ovulate regularly appear to have less impact. For men, obesity is linked to lower sperm quality and hormonal shifts that can impair production.
Environmental exposures play a smaller but real role. Couples living near major roadways, with higher exposure to nitrogen dioxide and fine particulate matter, have longer times to pregnancy and higher miscarriage risk. Evidence on common household chemicals like phthalates and BPA is less conclusive, with most studies showing little to no measurable effect on time to pregnancy.
What to Do if You Recognize These Signs
If you’re actively trying to conceive and you notice irregular cycles, pelvic pain, sexual dysfunction, or any of the patterns described above, you don’t need to wait out a full year before seeking answers. The 12-month guideline applies to couples with no known risk factors. Having even one red flag in your medical history is reason enough to start the conversation sooner. An initial evaluation is straightforward, and many causes of infertility are treatable once identified.