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 sexual 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 factsheet on infertility and in the report “1 in 6 people globally affected by infertility.”
- Primary infertility: No pregnancy has ever occurred.
- Secondary infertility: One or more pregnancies have occurred in the past, but the desire for a child is currently unfulfilled.
Important is the perspective: infertility does not automatically mean you can never become pregnant. It initially indicates reduced fertility and that a structured evaluation is sensible. At the same time, WHO and professional societies emphasise that infertility should be recognised as a relevant health issue—with fair access to diagnostics and treatment.
Early signs: When should you be alert?
Female infertility is not a single condition but an umbrella term. Some people notice nothing initially—other than that pregnancy is taking longer than expected. Others have clear signals early on.
- very irregular cycles or absent menstruation
- very heavy, very light or unusually prolonged bleeding
- severe period 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 a “proof” of infertility. They are, however, reasons to document your cycle and to speak specifically with your clinician about fertility and childbearing goals.
Common causes of female infertility
Professional societies such as ESHRE and ASRM broadly classify causes into hormonal disorders, anatomical changes, diminished ovarian reserve, genetic and immunological factors, as well as environmental and lifestyle influences. Often multiple factors are involved.
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 multiple small follicles on ultrasound.
- Signs of PCOS: irregular cycles, increased body hair, acne, weight gain, insulin resistance.
- Typical treatment components: weight normalisation, exercise, dietary changes, management of insulin resistance and medical ovulation induction.
Ovulation disorders without PCOS
Ovulation can also be absent or infrequent without PCOS. Common causes include thyroid dysfunction, elevated prolactin, major weight changes, eating disorders, intensive athletic training or significant stress.
- Warning signs: very long cycles, absent bleeding, large weight fluctuations.
- Treatment: stabilising hormone balance, for example thyroid medication, treatment for high prolactin and gentle cycle regulation.
Endometriosis
In endometriosis, tissue similar to the uterine lining is found outside the uterus, for example on the ovaries, fallopian tubes or the peritoneum. This can cause inflammation, adhesions and pain—and significantly reduce fertility.
- Typical symptoms are severe period pain, pain during sex and chronic lower abdominal pain.
- Treatment: pain management, hormonal therapy and, when trying to conceive, often minimally invasive surgery supplemented by fertility treatments such as IUI or IVF/ICSI.
Tubal factor: problems with the fallopian tubes
Blocked, scarred or damaged fallopian tubes prevent the egg and sperm from meeting or stop the embryo from reaching the uterus safely. Common causes include past pelvic infections, surgery or severe endometriosis.
- Diagnosis: contrast studies or specialised ultrasound techniques to assess tubal 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 the risk of miscarriage—especially if they deform the uterine cavity.
- Diagnostics: transvaginal ultrasound, 3D ultrasound and hysteroscopy.
- Treatment: hysteroscopic removal of septa, polyps or submucosal fibroids when these affect the uterine cavity.
Diminished ovarian reserve and age
With increasing age, both the number and quality of eggs decline. Some people experience premature ovarian insufficiency well before the usual age of menopause. Surgery on the ovaries, chemotherapy or radiotherapy can further reduce the reserve.
Useful markers include 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 hinder implantation or cause recurrent miscarriages. With a relevant history, genetic and immunological tests are often recommended to rule out rare but important causes.
Unexplained infertility
In some cases, no clear cause is found despite thorough diagnostics—this is called unexplained infertility. Current evidence-based ESHRE guidelines often recommend a combination of mild hormonal stimulation and intrauterine insemination before considering IVF. A concise summary is available in the ESHRE guideline on unexplained infertility and the accompanying patient leaflet.
Diagnostics: How is the evaluation carried out?
The fertility evaluation should give you clarity without overloading you with unnecessary tests. The American Society for Reproductive Medicine has published a clear framework that is widely used internationally as a guide.
- History and interview: cycle pattern, previous pregnancies, miscarriages, surgeries, infections, medications, medical history, family history, lifestyle.
- Physical and gynaecological examination: weight, blood pressure, thyroid assessment, gynaecological exam with swabs as needed.
- Cycle monitoring: documentation of cycle length, bleeding amount, pain and possible ovulation signs (cervical mucus, basal body temperature, ovulation tests).
- Hormone profile: FSH, LH, estradiol, AMH, prolactin, TSH and, if needed, androgens at the start of the cycle to assess ovarian reserve and hormone balance.
- Transvaginal ultrasound: uterus, endometrium, ovaries, antral follicles, cysts or fibroids.
- Tubal diagnostics: contrast studies or ultrasound techniques to check fallopian tube patency—depending on risk and findings.
- Additional imaging and endoscopy: hysteroscopy or laparoscopy if endometriosis, adhesions or structural changes are suspected.
- Genetics and immunology: additional tests for recurrent miscarriages, very early ovarian failure or relevant family history.
- Semen analysis: examination of the partner or donor according to current WHO standards (WHO Laboratory Manual 2021) to assess sperm count, motility and morphology.
The ASRM Committee Opinion “Fertility evaluation of infertile women” summarises these steps concisely and emphasises: women under 35 should begin evaluation after about twelve months without pregnancy; women aged 35 and older should begin after six months. You can find the summary on the ASRM website.
Treatment options: what really helps?
The appropriate therapy depends on cause, age, duration of the desire to conceive, health risks and your personal priorities. Modern fertility centres usually follow a stepwise plan—from less invasive measures to more complex procedures.
Optimising 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” describes concrete strategies to improve spontaneous chances of conception.
Medical ovulation induction
If ovulation is rare or absent, medications can stimulate egg maturation. Oral agents and, if needed, hormone injections are used to stimulate the pituitary or ovaries. 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 favourable conditions. The ESHRE guideline on unexplained infertility often recommends IUI with mild stimulation as a first active treatment step.
In vitro fertilisation (IVF) and ICSI
In IVF, multiple eggs are retrieved after hormonal stimulation and fertilised with sperm in the laboratory. In ICSI, a single sperm is injected directly into the egg. Resulting embryos are transferred to the uterus after a few days. These methods are 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 radiotherapy—cryopreservation of oocytes, 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 aspects should be carefully considered.
Success rates and prognosis: what are my chances?
The most common question from couples or individuals is: “How likely is it that treatment will work?” There is no exact number for each individual, but large registry data show typical ranges. The U.S. Centers for Disease Control and Prevention (CDC), for example, publishes national ART data annually with success rates by age group.
- Under 35 years, IVF success rates per embryo transfer in many registries are in the range of about 40 to 50 percent.
- Between 35 and 37 years they commonly fall to about 30 to 40 percent.
- Between 38 and 40 years rates often lie around 20 to 25 percent.
- From the early forties, they decrease per attempt to the low double-digit or single-digit percentages.
These figures are averages across many clinics and patient groups—your personal prognosis may be better or worse. The “National ART Summary” and state reports in the ART surveillance portal of the CDC give a good impression of real-world data.
More important than a single attempt is the cumulative chance over several well-planned treatment cycles. Time also plays a major role: the older the patient, the more egg quality and embryo stability decline. Early education and a realistic, shared strategy with your care team are therefore central.
Lifestyle, environment and prevention
You cannot influence every cause—but you can modify several risk factors. International organisations like WHO, ESHRE and ACOG repeatedly stress the importance of lifestyle and environmental factors for fertility and pregnancy outcomes.
Lifestyle and nutrition
- A body weight within a healthy range supports hormonal balance, ovulation and egg quality.
- Quitting smoking and moderating alcohol intake improve fertility and reduce pregnancy risks.
- Regular physical activity reduces stress, benefits metabolism and promotes overall well‑being.
- A Mediterranean-style diet with plenty of 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 plasticisers, pesticides and industrial compounds—can interfere with hormones. Expert groups like ESHRE have prepared concise fact sheets on environment 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.
Think about fertility preservation early
If you plan to delay childbearing for professional, personal or health reasons, or if a treatment that could damage the ovaries is planned, early counselling on fertility preservation is worthwhile. Options such as oocyte or embryo cryopreservation should be considered individually, medically and legally.
Emotional burden: You are not alone
Unfulfilled desire to have children is more than a medical diagnosis. Many affected people experience shame, grief, anger, envy or the feeling of having “failed.” Treatments can be physically demanding, appointments and costs hard to plan, and waiting times between cycles exhausting.
For this reason WHO and professional societies recommend psychosocial support as an integral part of fertility care. This can include specialised counselling at the fertility centre, psychotherapy, coaching, peer support groups or a well-moderated online community. What matters is that you 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 aged 35 and older.
- Independently of duration, seek immediate evaluation if clear risk factors are present—for example very irregular or absent cycles, known endometriosis, prior severe pelvic infections, severely reduced sperm quality in the partner or planned treatments that could damage fertility.
The first point of contact is usually your gynaecologist. Depending on findings, you may be referred to a specialised fertility centre that offers more diagnostics and treatment options—from cycle monitoring and IUI to IVF and fertility preservation.
Conclusion: Make informed decisions, step by step
Female infertility is common and complex—but more treatable today than ever before. Causes range from hormonal disorders, endometriosis and tubal problems to uterine changes, genetic and immunological factors, as well as environmental and lifestyle influences. At the same time, a wide range 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 to conceive 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 so maximises your chances of having the child you want.
