What is IUI (Intrauterine Insemination)?
IUI involves selecting healthy and strong sperm in sufficient quantity and injecting them into the uterus on the day the woman ovulates. Ovulation is stimulated using medication. This method gives sperm a higher chance of meeting the egg than natural intercourse. A very small catheter is inserted through the vagina (which doesn’t hurt but might feel slightly uncomfortable), and the selected sperm are injected through this catheter into the uterus, positioning them close to the ovulated egg for fertilization.
Who is IUI suitable for?
IUI is ideal for couples who’ve tried conceiving naturally for over a year without success and who want to try assisted reproductive technologies. It is especially suitable for women under 35 or those with endometriosis, ovulation issues, or unexplained infertility. IUI is not suitable for women with blocked fallopian tubes on both sides or for men with severely low sperm quality or ejaculation issues.
In some cases, even women over 35 may still be eligible for IUI if doctors assess their hormone levels and reproductive health and find them fit for this treatment. IUI generally offers a 15–20% chance of success on the first attempt, especially if it’s the first time undergoing fertility treatment. The uterus lining is often still in a healthy condition, and the eggs are responsive to stimulation.
Types of IUI:
- Oral Ovulation-Stimulating Medication
Doctors usually prescribe oral medication for 5 days before insemination. On day 10 of the cycle, the doctor performs an ultrasound to assess the number and size of egg follicles. If the follicles are of suitable size, a trigger shot is given to induce ovulation before proceeding with insemination. - Injected Ovulation-Stimulating Medication
If oral medication does not produce enough or adequately sized follicles (18–20 mm), doctors may switch to injectable medication based on hormone test results. This method is also often used for women over 35. Injectable medications are charged based on dosage and are not included in the standard IUI package.
What if the First IUI Attempt Fails?
If the first round of IUI is unsuccessful, doctors usually recommend:
- Trying IUI Again:
Typically, doctors allow up to 3 IUI attempts. Since success rates are relatively low per cycle, repeating the process allows doctors to adjust treatment and better understand the reasons for failure. - Additional Testing:
Before further IUI attempts, doctors might recommend more detailed tests such as tubal patency tests (e.g., HSG) or hormone tests to identify underlying issues. - Switching to IVF/ICSI:
For older women or those who don’t want to wait, switching to IVF or ICSI can significantly increase the chance of pregnancy — up to 70%.
Why Is IUI Limited to 3 Attempts?
If 3 IUI cycles fail, continuing may not be beneficial. Stronger medications like Clomid or Serophene used in repeated attempts can thin the uterine lining, making it harder for embryos to implant, especially if the lining becomes thinner than 5 mm. In such cases, it’s recommended to stop IUI and allow the uterus to recover.
At Beyond IVF, doctors don’t recommend more than 3 IUI attempts. Instead, they advise moving to IVF/ICSI, which is more effective and has fewer side effects from egg stimulation medication. IVF/ICSI also allows for closer monitoring throughout the treatment.
If you have concerns, you’re welcome to consult at Beyond IVF, or contact us via Line at @beyondivf for more information.