IUI Procedure Step by Step: A Clinical Guide for Gynaecologists

Intrauterine insemination (IUI) is often the first assisted reproductive treatment offered to couples. It is relatively simple, less invasive and less costly than IVF - but good results depend on careful patient selection, monitoring and technique. This guide walks through the process step by step.

1. Patient selection

IUI is suitable only when at least one fallopian tube is patent and there are adequate motile sperm. Common indications include:

• Unexplained infertility
• Mild male-factor infertility
• Ovulatory disorders such as PCOS, combined with ovulation induction
• Cervical factor or difficulties with intercourse
• Use of donor sperm

IUI is generally not appropriate with bilateral tubal blockage or severe male-factor infertility, where IVF or ICSI is more suitable. Age and duration of infertility should also guide how many IUI cycles are reasonable before moving on.

Before starting

• Confirm tubal patency (HSG or sono-salpingography)
• Review a recent semen analysis against WHO 6th edition reference values
• Assess ovarian reserve and the uterine cavity on ultrasound
• Counsel the couple about realistic success rates and risks, including multiple pregnancy

2. Natural or stimulated cycle

IUI can be done in a natural cycle or with ovulation induction using oral agents (letrozole or clomiphene) or low-dose gonadotropins. The aim of stimulation for IUI is usually one or two dominant follicles - not more. See our guide to ovulation induction protocols.

3. Follicle monitoring

Transvaginal ultrasound is used to track follicle growth and endometrial thickness, typically starting mid-follicular phase. Monitoring lets the clinician:

• Time the trigger or detect the LH surge
• Identify excessive response early
• Cancel or convert cycles when there are too many mature follicles, to reduce the risk of multiple pregnancy and OHSS

4. Trigger and timing

When the lead follicle reaches the target size, ovulation is usually triggered with hCG. IUI is commonly performed around 24-36 hours after the trigger, or the day after a detected urinary LH surge in natural cycles.

5. Semen preparation

The sample is collected after a short period of abstinence and prepared in the laboratory to concentrate motile sperm and remove seminal plasma. Common methods include:

• Density gradient centrifugation
• Swim-up

The post-wash total motile sperm count is an important practical guide to the chance of success. Correct labelling and witnessing of the sample is essential.

6. Performing the insemination

1. Confirm the patient's identity and verify the sperm sample with a second person
2. Position the patient and gently expose the cervix with a speculum
3. Clean away excess mucus from the cervix
4. Pass a soft IUI catheter gently through the cervix into the uterine cavity, avoiding the fundus
5. Inject the prepared sample slowly in a small volume
6. Withdraw the catheter gently

The procedure should be quick and minimally uncomfortable. Ultrasound guidance can help in difficult cases.

7. After the IUI

• Luteal support where indicated by the protocol
• A pregnancy test roughly two weeks later
• Clear advice on symptoms to report, such as those of OHSS

Common pitfalls

• Over-stimulation leading to multiple follicles
• Poor timing between trigger and insemination
• Traumatic catheter insertion causing bleeding or cramping
• Continuing IUI for too many cycles instead of moving to IVF when indicated

Train with ReproNest

ReproNest's Advanced Hands-on IUI & Ovulation Induction Masterclass covers patient selection, monitoring, sperm preparation and supervised IUI practice. Contact us for upcoming batches in Delhi NCR and Gurgaon.