Why Does IUI Fail?
IUI (Intrauterine Insemination) has a per-cycle success rate of 10–15% under ideal conditions (good sperm count, open tubes, regular ovulation, age under 35). This means 85–90% of IUI cycles do not result in pregnancy — even when everything looks right. After 3 failed IUI cycles, the cumulative success is still only 30–40%.
IUI fails for the same reasons natural conception fails — it just bypasses the cervix. Fertilisation, embryo quality, and implantation all still happen without any assistance. If any of these steps is compromised, IUI cannot fix it.
When to Move from IUI to IVF
Dr. Prashanthi Reddy's protocol at Mother Hospitals:
- After 3 failed IUI cycles in women under 35: Investigate before adding more IUI. Check again for tubal patency (HSG), uterine cavity (SIS or hysteroscopy), and re-evaluate sperm DNA fragmentation.
- After 2 failed IUI in women 35–38: Move to IVF. Time is the real constraint. Two more IUI cycles waste 4–6 months with no real improvement in success rate.
- After 1 failed IUI in women over 38 or 40: Proceed directly to IVF. IUI is not the right first-line for women in this age group.
- Any time sperm count <5 million motile after washing: Stop IUI and do ICSI-IVF. IUI requires a minimum sperm threshold — below it, the cycle should not proceed.
IUI vs IVF Success Rate Comparison
| Factor | IUI | IVF |
|---|---|---|
| Success rate per cycle | 10–15% | 45–55% |
| Time per cycle | 2 weeks | 4–6 weeks |
| Cost per cycle | ₹5,000–15,000 | ₹99,000 (all-inclusive) |
| Cost to achieve pregnancy | ₹50,000–1,00,000 (6–8 cycles) | ₹99,000–1,98,000 (1–2 cycles) |
| Controls fertilisation? | No | Yes (ICSI) |
| Can test embryo? | No | Yes (PGT-A) |
What to Investigate After 3 Failed IUIs
- Sperm DNA Fragmentation Test — high DFI (>25%) explains why sperm fertilise but embryos arrest early
- HSG or Laparoscopy — check if tubes opened adequately; mild hydrosalpinx can drain fluid into uterus and block implantation
- Hysteroscopy — check for polyp, fibroid, or septum in uterine cavity that prevents implantation
- Thyroid and prolactin — elevated TSH (>2.5) or prolactin impairs implantation even when IUI is done correctly
- NK cell testing — elevated natural killer cells in some women cause recurrent implantation failure
3 Failed IUIs — What Comes Next at Mother Hospitals?
Dr. Prashanthi Reddy does a systematic review after 3 IUI failures: investigative hysteroscopy (30-minute outpatient procedure), sperm DFI test, and updated hormone profile. If all clear: proceed to IVF with ICSI. If an issue is found: fix it, then decide on IUI vs IVF based on what was found.
→ IUI Treatment at Mother Hospitals | → IVF ₹99,000 All-Inclusive Package
Consult Dr. Prashanthi Reddy — Mother Hospitals, Boduppal
Germany-Trained IVF Specialist · ₹99,000 All-Inclusive Package · ART Act 2021 Certified