Sex 2 Days Post-Ovulation and Implantation
Having sex 2 days after ovulation does not help prepare for implantation and, based on the most recent high-quality evidence, may actually be detrimental to achieving pregnancy.
The Evidence on Peri-Implantation Intercourse
The timing of intercourse relative to implantation has been studied with conflicting results, but the most recent and rigorous evidence provides clarity:
Contradictory Findings
The 2020 study by Ecochard et al. found no negative effect of intercourse during the implantation window (5-9 days post-ovulation) on fecundability 1. This prospective study of 661 women across five European countries used sophisticated Bayesian modeling and found an adjusted fecundability ratio of 1.00 (95% CI: 0.76-1.13) for three or more acts of peri-implantation intercourse versus none 1.
However, an earlier 2014 study by Wilcox et al. found the opposite: cycles with 2 or more days of intercourse during the implantation window were significantly less likely to result in pregnancy (fecundability ratio 0.62; 95% CI: 0.42-0.91) 2. This study included 564 women providing 1,332 complete cycles 2.
The Critical Window for Conception
What matters most is intercourse BEFORE ovulation, not after. The fertile window is the 6-day period ending on the day of ovulation itself 3. Conception occurs only during this pre-ovulatory window, with the highest probability (0.33) when intercourse occurs on the day of ovulation 3. The probability drops to 0.10 when intercourse occurs 5 days before ovulation 3.
By 2 days post-ovulation, the egg is no longer viable for fertilization - the fertile window has already closed 3.
Understanding Implantation Timing
Implantation occurs 6-12 days after ovulation, with 84% of successful pregnancies implanting on days 8,9, or 10 4. This means that 2 days post-ovulation is well before implantation even begins 4.
The risk of early pregnancy loss increases with later implantation: only 13% of conceptuses implanting by day 9 resulted in early loss, compared to 82% for those implanting after day 11 4.
Practical Recommendations
For couples trying to conceive:
- Focus intercourse on the fertile window - the 6 days ending on ovulation day 3
- Aim for intercourse every 1-2 days beginning soon after the menstrual period ends in women with regular cycles 5
- The most fertile days are characterized by slippery, stretchy cervical mucus 5
- There is no evidence that intercourse after ovulation improves pregnancy rates 1, 3
Common Pitfalls to Avoid
- Don't rely on post-ovulation intercourse - the egg is only viable for fertilization for approximately 12-24 hours after ovulation 3
- Don't avoid intercourse during the implantation window based on the conflicting 2014 study - the more recent 2020 evidence found no detrimental effect 1
- Don't use commercially available vaginal lubricants as these might reduce fertility 5
The Bottom Line
Sex 2 days post-ovulation occurs after the fertile window has closed and before implantation begins. While the 2020 evidence suggests it doesn't harm pregnancy chances 1, it also doesn't help - the opportunity for conception has already passed 3. Couples should concentrate their efforts on the 6-day window ending on ovulation day for maximum fertility 3, 5.