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IUI which is the acronym for Intrauterine insemination is an assisted reproductive procedure that involves the direct placement of washed and concentrated sperm into the uterus around the ovulation time. Unlike in natural mating, so many barriers to the fertilization process are bypassed as the sperm only swims from the uterus to the fallopian tube, thus increasing the chances of conception.
IVF on the other hand is an acronym meaning In vitro fertilization. It involves a complex series of procedures used to ensure conception. In IVF, mature eggs are collected from the ovaries and fertilized in the lab. The embryo is then transferred to the uterus.
Indications IUI vs IVF
Intrauterine insemination and In Vitro fertilization can be used in some conditions. These may include:
- Endometriosis: Endometriosis or disorders of the endometrium of the uterus can reduce the chances of implantation.
- Sperm from donor male: In instances where women need to use donor sperm to get pregnant, IUI is mostly used. Depending on the conditions, IVF could be used too.
- Unexplained infertility. IUI is often performed as a first treatment for unexplained infertility with ovulation-inducing medications.
- Subfertility in the male: For males with low sperm quality and concentration, both procedures are helpful.
- Infertility in females: For females with cervical or ovulatory factor infertility, IUI and IVF have successfully been used to induce pregnancy.
- Semen allergy: Females with semen allergy could need artificial insemination as a means of conceiving.
Procedure: IUI vs IVF
Intrauterine insemination involves:
- Semen preparation: The preparation of the semen sample requires the removal of non-sperm and low-quality sperm elements of the sample.
- Monitoring for ovulation: Timing is essential in IUI thus, observation of the luteinizing hormone surge is required. In some, no medications for ovulation would be used. In others, drugs such as clomiphene citrate (Clomid), hCG (human Chorionic Gonadotropin), and FSH (follicle-stimulating hormone) have been employed to aid in ovulation of multiple eggs, increasing the chances of conception.
- Semen insemination: A day or two after ovulation detection, insemination is performed. A sterile speculum is inserted into the vagina, and a vial containing the concentrated sperm is inserted at the end of a catheter. The catheter is passed through the vagina to the uterus where the sperm is deposited. The catheter and speculum are then removed.
Unlike IUI, IVF is more complex and requires a series of tests and screening. These may include the
- Ovarian reserve testing: This helps to determine egg quality and quantity. Hormones such as follicle-stimulating hormone (FSH), estrogen, and the anti-mullerian hormone may also be checked.
- Semen analysis: A semen analysis helps to ensure the semen quality and concentration.
- Infectious disease screening: Different diseases such as hepatitis and HIV are tested for before IVF is performed.
- Uterine exam: An ultrasound of the uterus (sonohysterography) or an endoscopic examination of the uterus (hysteroscopy) is also essential before the procedure.
The procedure begins with the induction of ovulation. Medications that aid in ovarian stimulation (follicle-stimulating hormone (FSH), a luteinizing hormone (LH) are first administered. At about 8-14 days, human chorionic gonadotropin (HCG) or other medications for oocyte maturation are used when the follicles are ready for egg retrieval. Other medications to prevent premature ovulation and prepare the lining of your uterus may also be administered. Different factors may affect egg retrieval, and IVF would be canceled and adjustments made.
Egg/Sperm Retrieval and Fertilization
Egg retrieval is done before ovulation and requires sedation. A transvaginal or abdominal ultrasound is used with a thin needle inserted into the probe. The needle is attached to a suction device which aids in the collection. The eggs are then placed in a culture medium.
Typical side effects associated with egg retrieval may include bloating, constipation, cramping, breast tenderness, and spotting.
Sperm retrieval is done if the sperm is from a male partner. Following the retrieval of the egg and sperm, fertilization takes place. This can be done either through:
- Conventional insemination: During which healthy sperm and mature eggs are mixed and incubated overnight or
- Intracytoplasmic sperm injection (ICSI): In this case, a single healthy sperm is injected directly into each mature egg. This is used when the number of viable eggs is low or fertilization does not occur via conventional means.
Other procedures that may take place include:
- Assisted hatching: This is usually done in older women or for eggs that have been frozen as the zona pellucida is hardened by the freezing process.
- Preimplantation genetic testing: This is used to prevent the passage of unwanted genes to offspring.
Two to five days after egg retrieval and fertilization, embryo transfer is done. Unlike egg retrieval, it is usually painless so no sedative may be required. A catheter is inserted into the uterus and the embryo which is suspended in a fluid is deposited there. Successful implantation takes place about 6 to 10 days after.
IUI vs IVF
Despite being methods of assisted reproduction, some differences exist between IUI and IVF.
- Success rate: IUI has a lower success rate (4-13%) as compared to IVF with a success of (8-54%) depending on age.
- Procedure: Unlike IUI, fertilization occurs outside the body in IVF. IUI is also less stressful, less invasive, and less time-consuming than IVF. Intrauterine insemination is also 3 to 8 times cheaper than In Vitro fertilization.
- Range of use: IUI has several limitations and cannot be used for women of advanced ages, with fallopian tube damage or blockage, ovulation disorders, uterine fibroids, genetic disorders, fertility preservation, and impaired sperm production or function.
- Complications and risks: The major risks associated with IUI are infections, spotting, multiple pregnancies, and Ovarian Hyperstimulation Syndrome. IVF has more risks in addition to the aforementioned. These are premature delivery, low birth weight, miscarriage, ectopic pregnancy, birth defects, cancer, Egg-retrieval procedure complications, and stress.
Comparing IUI vs IVF, despite having more risks associated with it, the high success rate of IVF does justice to the procedure. Also, it is a last resort when alternative methods of assisted reproduction have failed.