IUI

IUI is intra-uterine insemination. Sperm is washed and concentrated in the laboratory, then placed directly into the uterus through a fine catheter around the time of ovulation. It is the simplest and most affordable treatment on the ladder, and works best as a short, planned course.

Where you'll meet it

Early, if it is going to come up at all. It is offered where the tubes are open and the sperm is reasonable, and it is the standard first route for single women and female couples using donor sperm. If the tests point somewhere harder, it gets skipped and the conversation goes straight to IVF.

What the procedure involves

Almost nothing, from your side. Ovulation is tracked, either on your own cycle or with mild stimulation from tablets such as letrozole or clomifene, and sometimes low-dose injections. Scans confirm a follicle is growing. A trigger injection may be used to fix the timing.

On the day, a semen sample is produced or a donor vial is thawed, and the laboratory prepares it, separating the motile sperm from the seminal fluid and concentrating them into a small volume. That washing step matters, because unprepared semen cannot be put into the uterus. Then a soft catheter through the cervix, a few seconds, and you get up and go to work. It feels much like a smear test, and it needs no anaesthetic.

What it does, and who it suits

IUI shortens the journey for the sperm and removes the timing problem. That is the whole of its mechanism. It puts a concentrated population of moving sperm past the cervix at roughly the right moment.

It does not fertilise anything for you, it does not bypass a blocked tube, and it cannot compensate for a sperm count that is genuinely low. At least one open tube is required, so a tubal patency test normally comes first, and a semen analysis decides whether there is enough to work with. Clinics usually look at the total motile count after washing rather than the raw figures.

The odds, and how many attempts

Per cycle the chances are modest, typically a low-teens percentage at best in favourable circumstances, and lower with age and with weaker sperm. Adding mild stimulation improves it somewhat and brings a risk of twins, which is why the scans are not optional.

Because the per-cycle figure is low and the cumulative figure flattens out, IUI is normally offered as a short course rather than indefinitely. Three or four attempts is a common plan, and if nothing has happened by then the best advice is to move up rather than keep going. Where age is pressing, that point comes earlier still, so agreeing the number at the start keeps your plan on track.

Why it is still worth considering

It is far cheaper than a cycle of IVF, and the difference is large enough that several attempts can cost less than one. There is no egg collection, no sedation and no stimulation of the kind that causes overstimulation. For people who want to try something gentler first, and who have the time to spend, that is a reasonable choice rather than a wasted one.

The IUI guide covers the process, the odds and the cost in full.

Questions to ask

Ask whether your tubes and sperm results actually support IUI, and what your total motile count after washing is expected to be. Ask how many attempts they would recommend before stopping, and what happens next. If stimulation is being added, ask how they will avoid a multiple pregnancy and at what point they would cancel.

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