Common Causes of Infertility

Understanding Infertility

Infertility affects 1 in 6 Australian couples who struggle to conceive naturally. It is defined as the inability to conceive after 12 months of regular, unprotected intercourse. Both men and women can experience fertility challenges, with causes ranging from hormonal imbalances and reproductive disorders to lifestyle and environmental factors.

Common Causes of Infertility in Women

1. Ovulation Disorders

Irregular or absent ovulation is a leading cause of infertility, accounting for 25-30% of female infertility cases. Conditions that affect ovulation include:

• Polycystic Ovary Syndrome (PCOS) – Affects 1 in 10 women, leading to irregular cycles and difficulty conceiving.
• Premature Ovarian Insufficiency (POI) – Early menopause before age 40.

2. Age-Related Fertility Decline

A woman’s fertility declines with age, especially after 35. By 40, the chance of conceiving naturally drops to 5% per month, compared to 20-25% at age 30.

3. Fallopian Tube Blockage & Uterine Conditions

• Endometriosis affects 1 in 9 women and can cause scarring that blocks the fallopian tubes.
• Fibroids or polyps or uterine abnormalities can interfere with implantation.

Common Causes of Infertility in Men

1. Low Sperm Count & Poor Sperm Quality

Male infertility accounts for 40-50% of all infertility cases. A healthy sperm count is over 15 million per milliliter, with at least 40% motility. Common causes of low sperm quality include:

• Varicocele – Enlarged veins in the scrotum, affecting sperm production.
• Hormonal imbalances – Low testosterone can impact sperm health.
• Infections & STIs – Can cause inflammation or block sperm transport.

2. Lifestyle & Environmental Factors

• Smoking, alcohol, and drug use reduce sperm count and motility.
• Obesity lowers testosterone and increases oestrogen, affecting fertility.
• Heat exposure from hot tubs or tight clothing can reduce sperm production.

When to Seek Fertility Support

• If you’ve been trying to conceive for 12 months (under 35) or 6 months (35 and older) without success.
• If you experience irregular cycles, painful periods, recurrent miscarriage, or known fertility issues.
• If a male partner has a history of low sperm count, testicular conditions, or hormonal imbalances.

Take the Next Step Toward Parenthood

Understanding the common causes of infertility is the first step in your fertility journey. If you’re struggling to conceive, Dr. Basu offers expert fertility assessments and personalised treatment options to help you achieve pregnancy.