Fertility depends on several factors:

Age – Women are at their most fertile around 25.  It starts to drop at 26 and declines at a greater rate after the age of 38.  Dr Goupil-Rousseau explains that this pattern is a general rule only and varies greatly from woman to woman.  The menopause can start as early as 38 for some, while other women can still have children at 45.

Weight – Anorexia can harm your fertility.  Being overweight can cause ovulation problems, as can fluctuating weight, caused by yoyo dieting.

Lifestyle – Too much alcohol, drugs and smoking cause bad-quality ovulation, but it’s not just you who should cut down – it also has a negative effect on his sperm too, so make sure the dad-to-be isn’t overdoing it!

Stress – If you are especially anxious, stress can also harm ovulation and even stop it altogether.  The ovaries are controlled by the pituitary gland, which is directly linked to brain function.