What is IUI, and how does it work?
Intrauterine insemination (IUI) is a fertility procedure where washed, concentrated sperm is placed directly into your uterus around the time of ovulation, shortening the distance sperm need to travel and increasing the number of healthy sperm near the egg. It's done in a clinic, takes only a few minutes, and doesn't require sedation. Many people describe it as similar to a pap smear in terms of discomfort. It's typically tried before IVF because it's simpler, less expensive, and less physically demanding, though it isn't the right option for every situation.
The 'washing' step matters: a lab separates the fastest, most active sperm from the rest of the semen, then concentrates them into a small sample. This also removes substances that would otherwise cause cramping if raw semen were placed directly into the uterus. The prepared sample is loaded into a thin catheter and passed through the cervix, timed to coincide with ovulation as closely as possible. Timing is usually tracked with ovulation predictor kits, blood hormone levels, or a trigger injection that predictably brings on ovulation.
Who is IUI usually recommended for?
IUI is typically recommended for mild male-factor infertility, ovulation problems, unexplained infertility, cervical-mucus issues, or when a single parent or same-sex couple is using donor sperm. It works best when at least one fallopian tube is open and sperm quality isn't severely reduced, since IUI still relies on the egg and sperm meeting and fertilizing on their own inside the body, rather than in a lab.
It's generally not recommended when both fallopian tubes are blocked, when sperm counts or motility are very low, or when there's significant endometriosis, since IUI can't overcome these physical barriers. Age plays a role too: chances decline as the person providing the eggs gets older, and providers sometimes recommend moving to IVF sooner for people over 35 or 40 who don't have time to spend on multiple lower-odds cycles. Your provider bases the recommendation on your specific test results, not a blanket rule.
What happens during an IUI cycle?
A typical IUI cycle starts with tracking ovulation, either naturally using ovulation predictor kits and cycle monitoring, or with the help of oral or injectable medications like letrozole, clomid, or gonadotropins that stimulate egg development. Your provider monitors follicle growth with ultrasound and sometimes bloodwork over roughly one to two weeks. Once a mature follicle is seen, you may take a trigger shot to time ovulation precisely, and the insemination is scheduled about 24 to 36 hours later.
On the day of the procedure, your partner provides a sperm sample (or a donor sample is thawed), and the lab washes and prepares it while you wait, usually 30 to 60 minutes. The insemination itself takes just a few minutes: a speculum is placed, a thin catheter delivers the sperm into the uterus, and you rest briefly afterward. Most people return to normal activity the same day. A pregnancy test is typically done about two weeks later, since testing earlier can give an unreliable result.
How well does IUI work?
IUI success varies widely by age, the reason for infertility, and whether it's combined with ovulation-stimulating medication — there's no single number that applies to everyone, and a clinic quoting one flat rate is oversimplifying. Chances are generally better for people under 35 with mild or unexplained infertility, and lower for those with significant male-factor issues, blocked tubes, or advanced age. Because per-cycle odds are modest for most people, providers often suggest trying several cycles, commonly framed as up to three or four, before reassessing the approach.
It helps to go in with realistic expectations: many people need more than one cycle, and needing several doesn't mean anything went wrong. Your provider should be able to give you a personalized estimate based on your test results, age, and diagnosis, rather than a generic percentage. If a set number of cycles hasn't worked, that's the natural point to talk about moving to IVF rather than continuing indefinitely with a treatment that isn't working for your situation.
What does IUI cost, and how many cycles do people try?
In the US, a single IUI cycle without medication typically costs a few hundred dollars for the procedure itself, though total cost rises significantly once monitoring, medication, and donor sperm (if used) are added — many people budget for several hundred to a few thousand dollars per cycle depending on what's involved. Insurance coverage varies enormously by state and plan; some states mandate fertility coverage and others don't, so it's worth calling your insurer directly before starting rather than assuming either way.
Most providers suggest trying a limited number of IUI cycles, often framed as three to four, before switching approaches, since success doesn't reliably keep improving with more attempts if the first several haven't worked. In countries with public healthcare systems like the UK or Canada, coverage for IUI varies by region and eligibility criteria, so ask your clinic what applies locally. Whatever the cost picture, it's reasonable to ask for a written breakdown before you commit to a cycle.
What are the risks and side effects?
IUI itself is a low-risk procedure — most people feel mild cramping during or shortly after, similar to period cramps, and this usually passes within a day. Because it doesn't involve surgery or sedation, serious complications are uncommon; a small number of people notice light spotting or, rarely, a minor pelvic infection. The bigger risks usually come from any ovulation-stimulating medication used alongside IUI rather than the insemination itself, since those medications can overstimulate the ovaries or cause more than one egg to be released.
The main medication-related risks are a higher chance of twins or triplets, since stimulating multiple follicles means more than one egg can be released and fertilized, and ovarian hyperstimulation syndrome (OHSS), a reaction to fertility drugs that causes swollen, bloated ovaries and, in rare severe cases, fluid buildup that needs medical attention. Call your provider the same day if you develop severe pelvic pain, significant bloating, rapid weight gain, difficulty breathing, or vomiting after a stimulated cycle — these can signal a reaction that needs prompt evaluation.
When do people move from IUI to IVF?
Moving from IUI to IVF is usually considered after several IUI cycles haven't led to pregnancy, typically after three to four attempts, or sooner if your workup shows a condition IUI can't address, like blocked tubes or severe male-factor infertility. Age is also a factor: because egg quantity and quality decline over time, providers often recommend skipping ahead to IVF sooner for people over 35 or 40 rather than spending months on lower-odds IUI cycles.
The decision isn't only medical — cost, time, and what you're personally willing to try all factor in, and there's no universally 'right' number of IUI cycles before switching. Some people choose to move to IVF earlier for these reasons, and that's a reasonable choice, not a failure to try hard enough. Talk through the trade-offs with your reproductive endocrinologist, who can weigh your specific results against the odds of each path.