What does infertility in women mean exactly?
The World Health Organization (WHO) defines infertility as a disease of the reproductive system in which a clinical pregnancy does not occur after at least twelve months of regular unprotected intercourse. Current data show that about one in six people of reproductive age worldwide are affected. You can find this classification in the current WHO fact sheet on infertility and the report “1 in 6 people globally affected by infertility.”
- Primary infertility: No pregnancy has ever occurred.
- Secondary infertility: There has been one or more pregnancies in the past, but the desire for a child is currently unfulfilled.
Important is the perspective: infertility does not automatically mean you will never become pregnant. It initially indicates reduced fertility and that a structured evaluation is reasonable. At the same time, WHO and professional societies emphasize that infertility should be recognized as a relevant health problem—with fair access to diagnostics and treatment.
Early signs: when should you pay attention?
Female infertility is not a single disease but an umbrella term. Some women notice nothing at first—apart from pregnancy taking longer than expected. Others have clear signals early on.
- very irregular cycles or absent periods
- very heavy, very light, or unusually long bleeding
- severe menstrual pain, pain during sex, or persistent lower abdominal pain
- signs of hormonal disorders such as increased body hair, hair loss, or severe acne
- recurrent miscarriages or very early pregnancy losses
None of these signs is proof of infertility. They are, however, reasons to document your cycle and to discuss fertility and your desire to conceive with your clinician.
Common causes of female infertility
Professional societies such as ESHRE and ASRM broadly divide causes into hormonal disorders, anatomical changes, reduced ovarian reserve, genetic and immunological factors, and environmental and lifestyle influences. Often multiple factors contribute.
Hormonal disorders and PCOS
Hormone-related cycle problems are among the most common causes worldwide. Polycystic ovary syndrome (PCOS) is particularly prevalent. Typical features are infrequent or absent ovulation, elevated androgen levels, and many small follicles on ultrasound.
- Signs of PCOS: irregular cycles, increased body hair, acne, weight gain, insulin resistance.
- Typical treatment components: weight normalization, exercise, dietary changes, treatment of insulin resistance, and medical ovulation induction.
Ovulation disorders without PCOS
Ovulation can also be infrequent or absent without PCOS. Common reasons include thyroid disorders, elevated prolactin, significant weight changes, eating disorders, intensive competitive sports, or pronounced stress.
- Warning signs: very long cycles, absent bleeding, large weight fluctuations.
- Treatment: stabilization of hormone levels, for example thyroid medication, treatment of hyperprolactinemia, and gentle cycle regulation.
Endometriosis
In endometriosis, tissue similar to the uterine lining grows outside the uterus, for example on the ovaries, fallopian tubes, or peritoneum. This can cause inflammation, adhesions, and pain—and significantly reduce fertility.
- Typical signs are severe menstrual pain, pain during sex, and chronic lower abdominal pain.
- Treatment: pain management, hormonal therapy, and for those desiring pregnancy often minimally invasive surgery, supplemented by fertility treatments such as IUI or IVF/ICSI.
Tubal factor: problems with the fallopian tubes
Adhesions, scarring, or blocked fallopian tubes prevent the egg and sperm from meeting or the embryo from safely reaching the uterus. Common causes are previous pelvic infections, surgeries, or extensive endometriosis.
- Diagnosis: contrast studies or specialized ultrasound techniques to check tube patency.
- Treatment: depending on severity, surgical reconstruction or direct IVF if the tubes are severely damaged.
Uterine factors and fibroids
Uterine malformations, polyps, and certain fibroids can interfere with implantation and increase miscarriage risk—especially if they deform the uterine cavity.
- Diagnostics: transvaginal ultrasound, 3D ultrasound, and hysteroscopy.
- Treatment: hysteroscopic removal of septa, polyps, or submucosal fibroids when they affect the uterine cavity.
Reduced ovarian reserve and age
With increasing age both the number and quality of eggs decline. Some women experience premature ovarian insufficiency well before typical menopause. Ovarian surgery, chemotherapy, or radiation can further reduce the reserve.
Helpful markers are the AMH level and the antral follicle count on ultrasound. They do not provide a “crystal ball” prognosis but help derive realistic chances and an appropriate treatment strategy.
Genetic and immunological causes
Certain chromosomal abnormalities, clotting disorders, or autoimmune diseases can impair implantation or lead to recurrent miscarriage. With a concerning history, genetic and immunological tests are often recommended to avoid missing rare but relevant causes.
Unexplained infertility
In some cases, despite thorough diagnostics no clear cause is identified—this is called unexplained infertility. Current evidence-based guidelines from ESHRE often recommend starting with a combination of mild hormonal stimulation and insemination before considering IVF. A clear summary is available in the ESHRE guideline on unexplained infertility and the accompanying patient leaflet.
Diagnostics: how does the evaluation proceed?
The fertility evaluation should give you clarity without subjecting you to unnecessary tests. The American Society for Reproductive Medicine has published a clear framework that is often used worldwide as guidance.
- Interview and medical history: cycle pattern, previous pregnancies, miscarriages, surgeries, infections, medications, medical history, family history, lifestyle.
- Physical and gynecological exam: weight, blood pressure, thyroid, gynecologic exam with swabs as needed.
- Cycle monitoring: documentation of cycle length, bleeding, pain, and possible ovulation signs (cervical mucus, basal temperature chart, ovulation tests).
- Hormone profile: FSH, LH, estradiol, AMH, prolactin, TSH and, if needed, androgens early in the cycle to assess ovarian reserve and hormonal balance.
- Transvaginal ultrasound: uterus, endometrium, ovaries, antral follicles, cysts or fibroids.
- Fallopian tube assessment: contrast studies or ultrasound techniques to check tube patency—depending on risk and findings.
- Additional imaging and endoscopy: hysteroscopy or laparoscopy if endometriosis, adhesions, or structural abnormalities are suspected.
- Genetics and immunology: additional tests for recurrent miscarriages, very early ovarian failure, or family concerns.
- Semen analysis: examination of the partner or donor according to the current WHO standard (WHO Laboratory Manual 2021) to assess sperm count, motility, and morphology.
The ASRM Committee Opinion “Fertility evaluation of infertile women” summarizes these steps concisely and emphasizes: evaluation should begin after about twelve months without pregnancy for women under 35, and after six months for women 35 and older. You can find the summary on the ASRM website.
Treatment options: what really helps?
The appropriate therapy depends on the cause, age, duration of the desire to conceive, health risks, and your personal priorities. Modern fertility centers usually follow a stepwise plan—from lower-effort measures to more complex procedures.
Optimizing natural fertility
Before invasive or very expensive steps are taken, it is worth addressing basic factors: well-timed intercourse, stress management, and habits such as smoking or alcohol. The ASRM statement “Optimizing natural fertility” outlines concrete strategies to improve spontaneous chances when trying to conceive.
Medical ovulation induction
If ovulation is infrequent or absent, medications can stimulate egg maturation. Oral medications and, if necessary, hormone injections that stimulate the pituitary gland or the ovaries are used. The goal is a well-monitored, predictable ovulation with as few, well-controlled follicles as possible.
Intrauterine insemination (IUI)
In IUI, processed sperm is placed directly into the uterus at the time of ovulation. It is useful for mildly reduced sperm quality, cervical issues, certain sexual dysfunctions, or unexplained infertility with otherwise favorable conditions. The ESHRE guideline for unexplained infertility often recommends IUI with mild stimulation as the first active treatment step.
In vitro fertilization (IVF) and ICSI
In IVF, after hormonal stimulation multiple eggs are retrieved from the ovaries and combined with sperm in the lab. In ICSI a single sperm is injected directly into the egg. The resulting embryos are transferred to the uterus after a few days. This is mainly used for tubal factor, severe male factor infertility, advanced endometriosis, or after unsuccessful simpler treatments.
Fertility preservation and donation options
Before therapies that can damage fertility—such as certain chemotherapy or radiation—cryopreservation of eggs, embryos, or ovarian tissue is often recommended. An evidence-based overview is provided by the ESHRE guideline “Female fertility preservation.” Depending on the country and legal framework, egg or embryo donation or surrogacy may also be options; legal and ethical issues should be carefully considered.
Success rates and prognosis: what are my chances?
The most important question for many couples or individuals is: “How likely is treatment to succeed?” There is no exact number for an individual case, but large registry data show typical ranges. The U.S. Centers for Disease Control and Prevention (CDC) publishes national ART (Assisted Reproductive Technology) data annually with success rates by age group.
- Under 35 years, success rates per IVF embryo transfer in many registries are in the range of about 40 to 50 percent.
- Between 35 and 37 years they typically fall to about 30 to 40 percent.
- Between 38 and 40 years rates are often in the range of about 20 to 25 percent.
- From the early forties onward they drop per attempt to the low double-digit or single-digit percentage range.
These numbers are averages across many clinics and patient groups—your personal prognosis may be better or worse. The CDC’s “National ART Summary” and state reports in the ART Surveillance portal provide a good view of real-world data: CDC.
More important than a single attempt is the cumulative chance across several well-planned treatment cycles. Time is also a major factor: with increasing age egg quality and embryo stability decline. Early counseling and a realistic, shared strategy with your care team are therefore central.
Lifestyle, environment, and prevention
You cannot influence every cause—but you can address some risk factors. International organizations such as WHO, ESHRE, and ACOG repeatedly emphasize the importance of lifestyle and environmental factors for fertility and pregnancy outcomes.
Lifestyle and nutrition
- A body weight in the healthy range supports hormonal balance, ovulation, and egg quality.
- Quitting smoking and moderating alcohol improve fertility and reduce pregnancy risks.
- Regular exercise reduces stress, benefits metabolism, and supports overall well-being.
- A Mediterranean-style diet rich in vegetables, fruit, whole grains, legumes, and healthy fats is associated in many studies with better fertility parameters.
- Folic acid is recommended before and at the start of a possible pregnancy to reduce the risk of neural tube defects.
Environmental factors and endocrine-disrupting substances
Certain chemicals—such as some plasticizers, pesticides, and industrial compounds—can interfere with the hormonal system. Expert groups like ESHRE have produced concise fact sheets on environmental factors and fertility.
- Avoid heating or storing hot food and drinks in problematic plastic containers when possible.
- Prefer glass, stainless steel, and ceramic, especially for long-term storage.
- Choose minimally processed foods when possible and read labels critically.
Consider fertility preservation early
If you plan to delay parenthood for career, personal, or health reasons, or if a therapy that may harm the ovaries is planned, early counseling on fertility preservation is worthwhile. Options such as egg or embryo freezing should be considered individually, medically, and legally.
Emotional burden: you are not alone
Unfulfilled desire for children is more than a medical diagnosis. Many people experience shame, grief, anger, envy, or the feeling of having “failed.” Treatments can be physically demanding, appointments and costs hard to plan, and the waiting between cycles draining.
For this reason WHO and professional societies recommend psychosocial support as an integral part of fertility care. This can include specialized counseling at the fertility center, psychotherapy, coaching, support groups, or a well-moderated online community. The important thing is to have a space where your feelings are acknowledged—regardless of the medical outcome.
When should you seek medical help?
Guidelines from WHO, ASRM, and ESHRE recommend similar time points for a fertility evaluation:
- After about twelve months of regular unprotected intercourse without pregnancy for women under 35 years.
- After about six months without pregnancy for women 35 years and older.
- Regardless of duration, seek help immediately if clear risk factors are present, such as very irregular or absent cycles, known endometriosis, prior severe pelvic infections, markedly reduced sperm quality in the partner, or planned therapies that may damage fertility.
The first point of contact is usually your gynecologist. Depending on findings, you may be referred to a specialized fertility center that offers more diagnostic and treatment options—from cycle monitoring and IUI to IVF and fertility preservation.
Conclusion: make informed decisions, step by step
Female infertility is common worldwide, complex—and today more treatable than ever. Causes range from hormonal disorders, endometriosis, and tubal problems to uterine changes, genetic and immunological factors, as well as environmental and lifestyle contributors. At the same time, a wide array of options is available: thorough diagnostics, evidence-based treatments, fertility preservation, and psychosocial support. The most important step is not to face your questions alone. If your desire for a child remains unfulfilled or you notice warning signs, an early, well-informed evaluation is worthwhile. Together with your care team you can develop a plan that balances medical facts, personal values, and financial considerations—and thus maximizes your chances of having the child you want.
