IUI Explained: Process, Who It Helps & Success Rates
Intrauterine insemination (IUI) is a first line fertility treatment that can improve the chance of pregnancy by placing prepared sperm directly into the uterus at the right time in the cycle. It is relatively simple, low intervention, and often used before moving to IVF in the right patients. This guide explains how IUI works, who it is best suited for, when it is unlikely to help, and what to expect in terms of success rates and cost.
When is IUI recommended?
IUI may be considered in situations such as:
Unexplained infertility
Mild male factor infertility, such as lower count or motility
Cervical factor issues, where mucus or the cervix may be a barrier
Ovulation disorders, often combined with ovulation induction medication
Mild endometriosis where fertility is not severely affected
Situations where intercourse timing is difficult due to travel, sexual dysfunction, or other constraints
When is IUI not usually recommended?
IUI is unlikely to help in the following scenarios:
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Severe male factor infertility, especially very low post wash sperm numbers
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Both fallopian tubes blocked, or significant tubal disease
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Significant pelvic adhesions or history of severe pelvic infection
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Severe endometriosis
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Inability to obtain a semen sample for insemination, such as anejaculation or severe ejaculatory disorders
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Multiple unsuccessful IUI cycles in the past, where escalation to IVF may be more appropriate
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Older age groups where time is limited, often over 40 depending on individual factors






