Female Infertility: Causes, Diagnosis and Treatment

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Written by Philomena Marx10 June 2025
A patient undergoing examination in a fertility clinic

Infertility is the inability to conceive after one year of regular, unprotected intercourse. Around 15% of couples worldwide are affected, and in about half of those cases the issue lies with the woman.

Definition: Primary vs. Secondary Infertility

Primary infertility refers to couples who have never achieved pregnancy. Secondary infertility applies when a couple cannot conceive despite having had at least one previous pregnancy.

Main causes

Female infertility is often multifactorial—hormonal, anatomical, genetic and environmental factors all play a part.

1. Polycystic Ovary Syndrome (PCOS)

PCOS affects 6–10% of women of reproductive age. Insulin resistance and raised androgen levels disrupt or halt ovulation.

  • Diagnosis: Rotterdam criteria – irregular cycles, hyperandrogenism, polycystic ovarian appearance on ultrasound.
  • Treatment:
    • A 5–10% weight loss significantly lowers androgen levels.
    • Metformin improves cycle regularity in insulin-resistant patients.
    • Letrozole increases live birth rates (27.5% vs. 19.1% with clomiphene; Legro et al. 2014).

2. Ovulation disorders without PCOS

Thyroid dysfunction (hypothyroidism or hyperthyroidism) and hyperprolactinaemia can stop ovulation.

  • Testing (cycle days 2–5): TSH, free T3/T4, prolactin.
  • Treatment: Levothyroxine for hypothyroidism; dopamine agonists (e.g. bromocriptine) restore ovulation in up to 70% of cases (PubMed 2006).

3. Endometriosis

Endometrial tissue implants outside the uterus, causing inflammation and adhesions.

  • Diagnosis: Laparoscopy with histological confirmation.
  • Treatment: Minimally invasive excision improves pregnancy rates by 20–30% (WHO 2013).

4. Tubal factor

Damage or blockage of the fallopian tubes—often from infection—prevents egg and embryo transport.

  • Diagnosis: Hysterosalpingography (sensitivity 65–95%) (Study 2012).
  • Treatment: Tubal flushing or surgical repair restores patency in 40–60%; severe blockages often require IVF.

5. Uterine anomalies and fibroids

Structural issues—such as a uterine septum or fibroids—can impede implantation.

  • Diagnosis: 3D ultrasound, hysteroscopy.
  • Treatment: Hysteroscopic resection raises live birth rates by 30–40% (RCOG Guideline No. 24).

6. Genetic and immunological factors

Balanced chromosomal rearrangements and antiphospholipid antibodies can prevent implantation.

  • Diagnosis: Karyotyping, autoimmune antibody panel.
  • Treatment: Low-dose heparin plus aspirin improves implantation rates in antiphospholipid syndrome (Cochrane Review).

7. Idiopathic infertility

Despite thorough evaluation, no cause is found in up to 15% of patients. IUI achieves 10–15% success per cycle; IVF yields 30–35% per cycle.

8. Male factor

A male factor contributes to infertility in about 40% of couples.

  • Semen analysis (WHO 2021): >15 million sperm/mL, >40% motility, >4% normal forms (WHO 2021).

Diagnostic workup

  1. Medical history and cycle logging (length, symptoms, lifestyle)
  2. Hormonal panel (days 2–5: FSH, LH, AMH, TSH, prolactin, estradiol)
  3. Transvaginal ultrasound (antral follicle count, fibroids, cysts)
  4. Hysterosalpingography (assessment of tubal patency)
  5. Laparoscopy if endometriosis or adhesions are suspected
  6. Genetic testing for recurrent pregnancy loss

Success rates by age

The German IVF Register (D·I·R) reported (2023) per embryo transfer:

  • Under 35 years: 30% live birth rate
  • 35–39 years: 20% live birth rate
  • 40 years and over: 10% live birth rate

Assisted reproductive techniques: IUI vs. IVF

IUI: 10–15% success per cycle; cost approx. €300–500
IVF: 25–35% live birth rate per cycle; cost approx. €3,000–5,000
Source: ESHRE ART Guidelines

Evaluation timeline

– Women aged 35 and over: begin evaluation after six months of trying
– Women under 35: begin evaluation after 12 months
Source: ESHRE 2015

Clinical checklist

  • Record cycle details (basal temperature, cervical mucus, ovulation signs)
  • Have medical records and current medication list ready
  • Book ultrasound and HSG appointments
  • Check your insurance cover for fertility procedures

Lifestyle and nutrition

A BMI of 20–24 kg/m² and a Mediterranean-style diet support reproductive health.

  • 400 µg folic acid daily and 1 g omega-3 fatty acids (Study 2016)
  • 150 minutes of moderate aerobic exercise per week
  • Avoid trans fats and highly processed foods

Environmental toxins

Endocrine disruptors such as BPA and phthalates can damage egg quality.

  • Use glass or stainless steel containers instead of plastic
  • Choose organic produce to minimise pesticide exposure
  • Drink filtered water to reduce PCBs and heavy metals (EFSA 2024)

Conclusion

Female infertility is complex and often multifactorial. A thorough evaluation, evidence-based treatments and tailored lifestyle changes can greatly improve your chances of a successful pregnancy. Collaborate closely with your fertility centre and follow established guidelines on your journey to parenthood.

Frequently Asked Questions (FAQ)