Intrauterine Insemination
  • What is IUI Treatment?
  • IUI Success Rates
  • IUI Risks
  • Natural vs Stimulated IUI
  • IUI FAQs
What is IUI Treatment?

What is IUI Treatment?

Intrauterine insemination (IUI) is a formal fertility treatment where the sperm, from either partner or a sperm donor is placed inside the woman’s womb. This is to encourage fertilisation, and the aim is to increase the number of sperm reaching the egg, whereby passing the vagina and the cervix. This may increase the chance of fertilisation by having the sperm directly entering the tubes.

IUI involves a laboratory procedure to separate fast-moving sperm from more sluggish or non-moving sperm. Sperm produced by masturbation are separated in the laboratory and are then placed into the woman’s uterus close to the time of ovulation when the egg is released from the ovary.

This treatment may be offered to improve the chance of conception if sperm quality is slightly low. It is not appropriate for cases when sperm quality is poor. The procedure is also not recommended when the fallopian tubes are damaged.

What are the indications for IUI?

One of the indications of IUI, intrauterine insemination, is that it is a less invasive form of treatment, and often the first line of treatment in a group of patients who are either coming for

  • donor insemination or
  • unexplained infertility or
  • mild male factor,
  • mild endometriosis or
  • polycystic ovarian syndrome.
  • Single women or women in a same sex relationship also may benefit with this form of treatment.

If there are minor problems with the quality of sperm, the chance of pregnancy declines, and thus the IUI treatment may help to improve pregnancy rates in those cases.

How does IUI work?

If you are not using fertility drugs, IUI is carried out between day 12-16 of your monthly cycle. We may ask that you carry out testing yourself using an ovulation predictor kit to detect the hormone surge that signals imminent ovulation. Mr. Gudi and Mr. Shah will offer scan monitoring to make the timing of insemination more accurate.

Alternatively, if we recommend that you use fertility drugs to stimulate ovulation, vaginal ultrasound scans will be used to track the development of your eggs. As soon as an egg is mature, you will be given a hormone injection (Ovitrelle/ Pregnyl) to stimulate its release.

The sperm will be inseminated 24 to 36 hours after your ovulation. The procedure is very similar to having a smear test with a speculum. A small catheter (a soft, flexible tube) is then threaded into your womb via your cervix. A prepared sperm sample, containing the best quality sperm, is inserted through the catheter. The whole process takes just a few minutes and is usually painless but some women may experience temporary, menstrual-like cramping. Following the procedure, we may recommend that you rest for 15-20 minutes before going home. The entire procedure is witnessed by at least two professionals to ensure that right sperm is inseminated in the right patient.

If your partner is unable to provide sperm, or if you do not have a male partner, you may wish to consider using donated sperm.

Tubal Patency Tests

Fallopian tubes should be open and healthy and there should also be no adhesions present that might prevent an egg from having access to either tube from the ovaries before the IUI process begins. A tubal patency test is usually carried out as part of your assessment either by hysterosalpingogram (HSG), Hycosy or by a laparoscopy. The recommended method for assessing the patency of your fallopian tubes is laparoscopy and dye testing.

IUI Success Rates

IUI Success Rates

The success rates of IUI depend on the woman’s age at time of treatment. The clinical pregnancy rate in women aged 36 or less is between 10-12% per treatment cycle.

In the event of three (or less, depending on your situation) unsuccessful IUI cycles, we would advise you to have a consultation to discuss other treatment options.

IUI Risks

IUI Risks

The biggest risk is that ovarian stimulation can develop into multiple follicles and in these cases, cycles would need to be abandoned. Regular scans are necessary and we generally start scanning between day seven and day eight of the cycle and may require more frequent scans to know the time of the trigger. If at any stage we see more than three follicles, we would abandon treatment. We may also abandon treatment with more than two follicles if you want to reduce the risk of having twins. If abandoning the treatment is necessary, further plans will need to be made after consultation with us.

Natural vs Stimulated IUI

Natural vs Stimulated IUI

There are two forms of IUI:

  1. Natural cycle IUI without any hormonal stimulation.
  2. Medicated IUI
    • Oral tablets with IUI
    • Stimulated IUI

Natural IUI

Natural IUI is the simplest form of IUI. It does not require the use of any fertility drugs. It is usually performed around the time of ovulation which could vary between day 12 and day 16 in a large number of women.

This is best suited for women who have a regular cycle where ovulation can be predictable. It is not as suitable for women with irregular cycles, since predicting ovulation is more difficult and it takes a longer time to detect it with a scan.

In those women having a natural cycle of IUI would be asked to come in for a scan between day eight and day ten to check for follicular growth, following which they would be monitoring the follicles using the LH test to check for ovulation. The surge of the LH hormone indicates that ovulation is imminent.

We generally prefer to give a trigger injection which would ensure that the eggs could be released and that if the LH test is positive, we would ask you to contact us as soon as possible, otherwise we generally would arrange for a scan in two to three days’ time to perform the trigger. The IUI is generally done the day after the LH surge when ovulation is likely to occur.The disadvantage of this treatment is that in some cases ovulation can be missed and the treatment would need to be stopped.

Stimulated IUI

Stimulated IUI may achieve a slightly better chance of pregnancy. This is by generally generating more than one follicle and though it would increase the chance of pregnancy, it also slightly increases the chance of multiple pregnancies .

Fertility drugs used are of two types, either using oral tablets or using injections. The oral tablets I use are called

  • Clomiphene or
  • Letrozole

The injections are gonadotropins and these could be FSH and LH, the common names being

  • Gonal F,
  • Benfola,
  • Meriofert,
  • Fostimon and
  • Menopur

The use of these fertility drugs can be advantageous because they stimulate the ovaries to produce at least one egg in each cycle. This works extremely well in women with unexplained infertility as well as women with irregular cycles.



How many cycles of IUI are advised and what is the success?

Studies suggest that between two and three cycles of IUI achieve the best chance of success, and if after three cycles of IUI a pregnancy does not occur, then it’s much better to proceed with treatment with other forms of assisted conception.

Successive cycles can be tried, especially if the ovary does not contain any cysts and the ovarian response is very good, and success rates seem to be much better.
It is essential that the body mass index, the height and weight calculation should be less than 35 to be eligible for IUI treatment.

The success rates of IUI range between 10 and 15 per cent in cycles and they seem to be highest using stimulated techniques. The success rates are lower in women over the age of 38 ranging from 5-8% One of the major complications of stimulated IUI is that it increases the chance of multiple pregnancies. After six cycles of IUI, the chances of pregnancy tend to decrease and thus the evidence does suggest that the maximum chance of pregnancy seems to happen in the first three cycles.

What is the minimum quantity of sperm needed for IUI

IUI also gives us better evidence about the quality of sperm to a certain extent, and if the washed prepared sample of sperm more than five million sperm, the chances of pregnancy are certainly much better and IUI may be an appropriate treatment.

If the washed sample shows a very low level of motile sperm, then IVF is a much better treatment option. Success rates are also affected by age and over the age of 37, chances of pregnancy start declining, and over the age of 40, chances of pregnancy are significantly lower.

How are medications given?

Oral agents can be given from day two of the period to day six of the period, and these could be in the form of Clomiphene or Letrozole. The aim of these drugs is to generate and to release FSH and generate the follicles from growing. A significant number of women would ovulate with this dose and sometimes this treatment does not work and ovulation does not occur, and alternatives have to be sought either by extending the dose of these tablets in some cases or moving to a more successfully outcome which is gonadotropins.

Gonadotropins are injections and these contain FSH and they come in various forms under Meriofert, Fostimon, Gonal F and Benfola. Their primary aim is to increase the level of FSH which is the follicle stimulating hormone, and start pushing the follicles towards ovulation. These are again started by a scan on day two of the period on a planned date and usually a scan is booked between day seven and day ten to assess whether follicular growth is happening.

When the pregnancy test is done?

Results following the insemination – we would ask you to wait between 12 and 14 days to find out if the treatment has been successful. This wait is extremely anxious and after two weeks we will be able to review the results. If the test is positive , a scan is booked in 3 weeks. If unfortunately the test is negative, an appointment will be offered to discuss the next options.

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