Intrauterine Insemination (IUI) is a straightforward fertility treatment that aims to increase the chance of conception by bypassing several natural barriers. The procedure involves placing a carefully prepared and concentrated sperm sample directly into the uterus. IUI is often a first-line treatment option for couples experiencing mild male factor infertility, unexplained infertility, or for individuals utilizing donor sperm. By shortening the distance the sperm must travel, IUI increases the number of high-quality, motile sperm that reach the fallopian tubes where fertilization occurs.
Preparing for the Insemination Cycle
The success of IUI depends on precise timing, requiring coordination between the patient and the medical team. The process begins with baseline testing, often including a transvaginal ultrasound and blood work, to assess the ovaries and confirm the start of the menstrual cycle. The patient then begins a protocol of oral medication or injectable hormones to stimulate the ovaries to mature one or more eggs.
Throughout the stimulation phase, the patient undergoes regular monitoring appointments. These appointments use blood tests to track hormone levels, such as estradiol, and ultrasounds to measure the size of developing ovarian follicles. Monitoring ensures the follicles reach an optimal size (typically around 18 millimeters) without growing too many, which increases the risk of a multiple pregnancy. Once the lead follicle is mature, a specialized injection of Human Chorionic Gonadotropin (hCG), often called a “trigger shot,” is administered to initiate the final maturation and release of the egg. This guarantees that ovulation will occur within a predictable window, usually about 36 hours later, allowing the procedure to be scheduled precisely.
Processing the Sperm Sample
Before insemination, the semen sample must be prepared in the laboratory, a process often called “sperm washing.” The partner provides a fresh sample, or a cryopreserved donor sample is thawed, and then mixed with a specialized solution. This solution separates the sperm cells from the seminal fluid, non-motile cells, and debris.
A primary goal of this preparation is to remove prostaglandins, naturally occurring chemicals present in the seminal fluid. If raw semen were introduced directly into the uterus, these prostaglandins could trigger severe uterine cramping and contractions. Techniques like density gradient centrifugation concentrate the healthiest, most active sperm into a small volume suitable for uterine insertion. This final, concentrated sample contains only the most viable sperm, enhancing the probability of them reaching and fertilizing the egg.
The Intrauterine Insemination Procedure
The IUI procedure is quick, typically lasting one to five minutes, and is similar to a routine gynecological examination. The patient lies on an exam table with their feet in stirrups. The clinician first inserts a speculum into the vagina to visualize the cervix, which may then be lightly cleaned with a sterile solution to remove mucus or bacteria.
The concentrated, “washed” sperm sample is drawn into a thin, flexible catheter designed for the procedure. The clinician gently threads the catheter tip through the cervix opening and advances it into the uterine cavity. Unlike natural conception, where sperm must navigate the cervix, the catheter places the sperm directly into the uterus.
Once the catheter is positioned, the clinician slowly injects the small volume of prepared sperm into the uterus. This precise placement maximizes the number of motile sperm available for transport into the fallopian tubes. After delivery, the catheter and speculum are removed, concluding the treatment.
Post-Procedure Care and Timeline
Immediately following insemination, the patient is often asked to remain lying down for a short period, typically 10 to 30 minutes, though evidence suggests this has minimal impact on success rates. It is common to experience mild cramping or light spotting for a day or two, usually resulting from the catheter passing through the cervix. Patients are advised to resume light to moderate daily activities but should avoid strenuous or high-impact exercise.
The next phase is the “two-week wait,” the time between the procedure and when a reliable pregnancy test can be performed. During this period, some patients may be prescribed progesterone supplements (administered vaginally or orally) to support the uterine lining and optimize conditions for implantation. Approximately 14 days after the IUI, a blood test is scheduled to measure the level of the pregnancy hormone, beta-hCG, to determine if the cycle was successful.