Pregnancy Risk from Intercourse on Day 22
The chance of pregnancy from intercourse on day 22 is very low to negligible in a standard 28-day cycle, as this falls well outside the fertile window, which ends on the day of ovulation (typically days 9-20, with peak fertility days 12-16). 1
Understanding the Fertile Window
The fertile period is biologically limited to approximately 6 days ending on the day of ovulation, when sperm can survive to meet a viable egg 2:
- Sperm survival: Sperm remain viable for an average of 1.4 days in the female reproductive tract, with only a 5% probability of surviving beyond 4.4 days and 1% probability beyond 6.8 days 3
- Egg viability: The ovum survives approximately 0.7 days (less than 24 hours) after ovulation 3
- Conception window: Nearly all pregnancies result from intercourse occurring during the 6-day period ending on ovulation day, with conception probability ranging from 0.10 (five days before ovulation) to 0.33 (day of ovulation itself) 2
Cycle-Specific Considerations
Standard 28-Day Cycle
For a typical 28-day cycle, ovulation generally occurs between days 9-20, with most women ovulating around day 14 1. Day 22 falls 2-8 days after typical ovulation has already occurred, placing it firmly in the post-ovulatory infertile phase 4, 1.
Shorter Cycles (25 Days or Less)
If the cycle is shorter than 26 days, the fertile window shifts earlier (typically days 6-11), making day 22 even further removed from the fertile period 4. In a 25-day cycle, ovulation occurs around days 11-12, meaning day 22 would be approximately 10 days post-ovulation 4.
Longer or Irregular Cycles
The critical caveat: If the cycle is significantly longer than 28 days or highly irregular, ovulation may occur later, potentially making day 22 closer to or within the fertile window 1. However, without specific cycle length information, this scenario is less common.
Clinical Reality
- Most women incorrectly estimate their ovulation day: In one study of women trying to conceive, only 12.7% correctly identified their ovulation day, with the median error being 2 days off (range -10 to +27 days) 5
- Only 55% of estimated ovulation days fell within the actual fertile window 5
- The standard assumption of day 14 ovulation (used by 35.5% of women) is often inaccurate for individual cycles 5
Bottom Line
For a standard 28-day cycle, intercourse on day 22 carries minimal to no pregnancy risk, as it occurs well after the fertile window has closed. 2 The biological constraints of gamete survival make conception virtually impossible at this point in the cycle 3. However, if cycle length is unknown or irregular, there remains theoretical uncertainty about when ovulation actually occurred 1.