IUI Explained
Understanding Intrauterine Insemination (IUI)
Intrauterine insemination (IUI), sometimes called artificial insemination, is a fertility treatment in which specially prepared sperm is placed directly into the uterus around the time of ovulation. The aim is to increase the number of sperm reaching the egg, improving the chance of fertilisation.
IUI is a relatively simple procedure and is less invasive than IVF. For some individuals and couples, it may be recommended before moving on to more complex fertility treatments.
What Is IUI?
During a natural conception, sperm must travel through the vagina, cervix and uterus before reaching the fallopian tubes, where fertilisation usually takes place.
During IUI, the sperm is placed directly into the uterus using a thin, flexible catheter. This allows more healthy sperm to reach the fallopian tubes, reducing some of the barriers they would normally face.
The procedure itself usually takes only a few minutes and does not require surgery or a general anaesthetic.
When Might IUI Be Recommended?
Your fertility specialist may recommend IUI if:
You have unexplained infertility.
There are mild male fertility problems, such as a slightly reduced sperm count or reduced sperm movement.
You have difficulty with intercourse because of pain, erectile dysfunction or other medical conditions.
You are using donor sperm.
You have problems with cervical mucus that may prevent sperm reaching the uterus.
Ovulation is being stimulated with fertility medication.
IUI is not suitable for everyone and is less likely to be successful if the fallopian tubes are blocked or severe male infertility is present.
Who Is IUI Suitable For?
IUI may be considered if:
At least one fallopian tube is open.
Ovulation is occurring naturally or can be stimulated with medication.
The sperm quality is suitable for insemination.
No major abnormalities of the uterus have been identified.
Your healthcare team will usually recommend investigations such as blood tests, ultrasound scans and assessment of the fallopian tubes before suggesting IUI.
How Does the Procedure Work?
A typical IUI cycle involves several steps.
Monitoring the Menstrual Cycle
The timing of the procedure is very important. Your cycle may be monitored using blood tests and ultrasound scans to identify when ovulation is likely to occur.
Some people undergo IUI during a natural cycle, while others receive fertility medication to stimulate ovulation.
Preparing the Sperm
A semen sample is collected on the day of treatment.
The sample is then "washed" in the laboratory. This process removes the seminal fluid and concentrates the healthiest, most active sperm.
The Insemination
A small speculum is inserted into the vagina, similar to a cervical smear.
A thin catheter is gently passed through the cervix into the uterus, and the prepared sperm is slowly released.
The procedure usually takes only a few minutes.
Does IUI Hurt?
Most people find IUI causes little or no pain.
Some experience mild discomfort similar to a cervical smear or mild period cramps while the catheter passes through the cervix.
Light spotting afterwards is also common and is usually nothing to worry about.
What Happens After IUI?
Most clinics recommend returning to normal daily activities shortly after the procedure.
There is usually no need for bed rest.
The fertilised egg, if conception occurs, must still travel to the uterus and implant naturally, just as it would after natural conception.
How Successful Is IUI?
Success rates vary considerably depending on:
Age.
The cause of infertility.
Sperm quality.
Whether fertility medication is used.
The number of treatment cycles completed.
In general, younger women and those with no significant tubal or sperm problems tend to have the highest success rates.
Your fertility specialist can discuss your individual chances based on your medical history.
What Are the Risks?
IUI is considered a low-risk procedure.
Possible risks include:
Mild cramping.
Light bleeding.
Infection (rare).
Multiple pregnancy if fertility medication stimulates the release of more than one egg.
Ovarian hyperstimulation syndrome (OHSS) when fertility medication is used, although this is much less common than during IVF.
Advantages of IUI
Less invasive than IVF.
Usually less expensive than IVF.
Quick procedure.
No surgery or general anaesthetic.
Can be performed using partner or donor sperm.
Limitations of IUI
IUI does not overcome every cause of infertility.
It is unlikely to be successful if:
Both fallopian tubes are blocked.
Severe male infertility is present.
There is significant damage to the reproductive organs.
Fertilisation problems occur outside the uterus.
In these situations, IVF or other fertility treatments may offer a better chance of pregnancy.
Frequently Asked Questions
How long does IUI take?
The insemination itself usually takes only a few minutes, although the appointment may last around 30–60 minutes.
Can I return to work afterwards?
Yes. Most people can return to normal activities immediately.
Is IUI the same as IVF?
No. During IUI, fertilisation takes place naturally inside the body. During IVF, eggs are fertilised in a laboratory before an embryo is transferred into the uterus.
How many cycles of IUI might I need?
Some people become pregnant after the first cycle, while others require several attempts. Your fertility specialist will discuss how many cycles may be appropriate for your individual circumstances.
A Gentle Reminder
Being offered IUI doesn't necessarily mean your fertility journey will be straightforward or that IVF will be needed later. For many people, IUI is an appropriate first treatment option and can provide a successful pathway to pregnancy. Every fertility journey is unique, and your healthcare team will recommend the treatment that best fits your individual circumstances.