Intrauterine insemination (IUI) is a common fertility treatment technique. For couples struggling to conceive, optimizing the timing of IUI and deciding between single or double insemination can significantly impact pregnancy rates.
Does Timing Really Matter?
Typically, IUI is scheduled 36 ± 2 hours after hCG injection to closely match the moment of ovulation. Performing IUI at this interval is proven to yield the best chances for fertilization because it maximizes the presence of sperm when the egg is released. Research shows little benefit in changing this window, so most fertility clinics follow this protocol for improved outcomes.
Single vs. Double IUI: Understanding the Difference
The number of inseminations performed during each cycle may also influence pregnancy success.
- Single IUI is usually effective—particularly for postovulatory cycles.
- Double IUI (performed before and after ovulation) is sometimes recommended, especially in preovulatory cases or when sperm quality is a concern.
- In cases of male factor infertility, double IUI has demonstrated increased pregnancy rates, making it a preferred choice when sperm motility or count is low.
Clinical Guidance
- Schedule IUI 33–39 hours after hCG for best results.
- Consider single IUI for most cycles unless specific factors warrant extra coverage.
- Choose double IUI for preovulatory cycles or male factor infertility, as evidence supports higher success rates in these scenarios.
Conclusion
The precise timing of IUI and the number of procedures per cycle do influence pregnancy rates. Most patients benefit from a single, well-timed IUI, while double IUI is reserved for select cases—primarily male factor infertility—where it can significantly improve the odds of conception. Always consult a fertility specialist to individualize your treatment plan for optimal success.