IUI vs IVF: Which Fertility Treatment Is Right for You?

IUI and IVF are the two treatments most people weigh after the first rounds of testing. They are often presented as steps on a ladder, and for many people they are, but they work in very different ways and suit different problems. This guide explains what each involves, who each helps, how often each works and what each costs, using guidance from ASRM and ACOG and national data from SART.

What is the difference between IUI and IVF?

IUI (intrauterine insemination) places washed, concentrated sperm directly into the uterus around ovulation, so more sperm reach the fallopian tubes where fertilization happens naturally.¹ IVF (in vitro fertilization) takes eggs out of the ovaries, fertilizes them with sperm in a laboratory, and transfers a resulting embryo into the uterus.²

How does IUI work?

The semen sample is "washed" in the lab to concentrate the sperm and remove seminal fluid, which can take up to 2 hours.¹ Near ovulation, a clinician places a speculum, passes a thin catheter through the cervix and slowly injects the sperm into the uterus. ASRM says the procedure takes a few minutes and is usually painless, though some people have mild cramps or spotting for a day or two.¹ IUI can be done in a natural cycle or combined with ovulation medicines such as clomiphene, letrozole or injectable gonadotropins.²

How does IVF work?

IVF happens in cycles. Medicines stimulate the ovaries to mature several eggs, a needle removes them, they are fertilized in the lab (either by mixing with sperm or by injecting one sperm into each egg), and a few days later an embryo is placed in the uterus. Healthy embryos that are not transferred can be frozen.² The stimulation phase usually means daily injections for about 10 to 12 days, with blood tests and ultrasounds to track the ovaries.⁶ Our IVF step by step guide walks through each stage and decision.

Who is IUI best for?

ASRM says IUI works best for:¹

• Unexplained infertility, usually combined with ovulation medicine. For this group, ASRM says the pregnancy rate with IUI plus ovulation medication is double that of no treatment.
• Cervical problems, such as scarring from cervical surgery, that keep sperm out of the uterus.
• Problems with sperm delivery, such as erection or ejaculation difficulties or retrograde ejaculation.
• Donor sperm, for single people, same-sex couples, or when a partner has no sperm.

IUI does not work as well when sperm counts are very low or sperm are severely abnormal, and it does not help severe tubal disease, moderate to severe endometriosis or a history of pelvic infections.¹ If you are using donor sperm and not sure you need a clinic yet, our at-home insemination guide explains how home insemination (ICI) differs.

Who is IVF best for?

ACOG lists these reasons for IVF: damaged or blocked fallopian tubes that cannot be repaired, severe endometriosis, primary ovarian insufficiency, some male factor infertility, and unexplained infertility.² IVF is also the route for using donor eggs, gestational carriers, genetic testing of embryos, or freezing embryos for later. Age matters as much as diagnosis, because both the number and the quality of eggs decline with age, with a faster fall from 35 to 40.⁶ That is why a specialist may suggest IVF sooner for someone in their late 30s or 40s. See getting pregnant after 40 for what changes.

IUI vs IVF success rates

IVF success rates in the US are reported by SART. In the final 2023 data for people using their own eggs, the share of egg retrievals that led to a live birth, counting all embryo transfers within a year, was:³

There is no comparable national registry for IUI, and IUI success varies a great deal with age, diagnosis and medicines. FertilityIQ, which compiles patient and clinic data, estimates IVF has 3 to 5 times higher success rates than IUI.⁴ ASRM adds that IUI success can be better when inseminations are repeated each month, and depends on age, diagnosis and whether fertility medicines are used.¹ Ask any clinic for its own IUI results by age.

IUI vs IVF cost

IUI is far cheaper per cycle. FertilityIQ estimates IVF is 5 to 40 times more costly than IUI and puts a typical US IVF cycle at about $22,000 as of 2019, including medication.⁴ But cost per baby is what matters. FertilityIQ notes that after one or two IUIs the chance of success stops improving, so cost per baby rises steeply, which is when IVF can become the better value.⁴ Insurance changes the math: some states require coverage of IUI, IVF or both. Our IVF cost guide breaks down prices, add-ons and state mandates.

Risks of IUI and IVF

The main risk of both is a multiple pregnancy. With IUI, it comes from ovulation medicines that develop several eggs; ACOG says the risk is higher with gonadotropins, and a cycle may be postponed if too many eggs are developing.² With IVF, it depends on how many embryos are transferred; ASRM and SART recommend transferring a single embryo when eggs come from someone under 38 or the embryo has been genetically tested.⁵ Ovarian stimulation, especially with gonadotropins, can cause ovarian hyperstimulation syndrome; ACOG says most cases are mild, though severe cases may need a hospital stay.² ASRM says IUI does not increase the risk of birth defects and the risk of infection after IUI is small.¹

How doctors decide: IUI first or IVF?

A specialist weighs your age, how long you have been trying, the results of both partners’ tests (tubes, ovulation, ovarian reserve and semen analysis), and your budget and insurance. ASRM says unexplained infertility is the most common reason for IUI;¹ our unexplained infertility guide covers the evidence. When tubes are blocked or sperm counts are very low, IUI is unlikely to help and IVF is usually the first treatment. If you have not had a full evaluation, read when to see a fertility specialist first, and see the Treat hub for all options.