The first period (menarche) occurs on average at the age of 12-13 years and ceases during menopause at the age of 50 years. Although women are able to conceive on most days of the cycle, the maximum potential for conception occurs two days prior and two days after ovulation. This time frame varies amongst women, as well as amongst different cycles of the same woman. The oocyte may be fertilised up to two days after the day of ovulation. Sperm survives between 2-3 days in the female reproductive tract, 5 days at maximum. These small variations are important for couples using natural contraception based on the day of the cycle.

The chances of spontaneous conception for women are affected primarily by age and are the following:

• 75% will conceive within 1 year
• 91% will conceive within 4 years

• 66% will conceive within 1 year
• 84% will conceive within 4 years

• 44% will conceive within 1 year
• 64% will conceive within 4 years

In general, couples that have been unsuccessful after a year of active attempts, should consult a Reproductive Specialist. In case of severe medical history, such as history of miscarriage, gynaecological surgery, patient age over 35 years etc, quicker consultation with a specialist is recommended, in order not to lose more precious time.