Cumulative probability of conceiving a clinical pregnancy by the number of menstrual cycles
| Age category, years | Pregnant after 1 year (12 cycles), % | Pregnant after 2 years (24 cycles), % |
|---|---|---|
| 19–26 | 92 | 98 |
| 27–29 | 87 | 95 |
| 30–34 | 86 | 94 |
| 35–39 | 82 | 90 |
From NICE guideline 156. Cumulative probability of conceiving a clinical pregnancy by the number of menstrual cycles attempting to conceive in different age categories (assuming vaginal intercourse occurs twice per week) (Reproduced with permission: Dunson DB, Baird DD, Colombo B [2004]. Increased infertility with age in men and women. Obstetrics and Gynecology 103: 51–6).