Why can't I get pregnant - what are the reasons?

The main reasons are:

• Advancing age, predominantly women
• Fallopian tubes factors (blocked or damaged tubes, missing tubes)
• Sperm problems: Semen quality / low sperm count
• Ovulatory problems
• Hormonal factors
• Weight: Being overweight or underweight
• Smoking
• A condition known as Polycystic Ovaries (PCOs)
• Endometriosis