Intrauterine Insemination (IUI)

Monash Biotech

October 18th, 2024

Intrauterine Insemination (IUI)

Intrauterine Insemination (IUI) is a procedure that treats the infertility challenge of couples. Intrauterine Insemination or IUI involves the placement of sperm cells directly into the uterus to increase the probability of fertilization. It is a painless process done in the absence of an anesthetic.

The procedure involves preparing the sperm cells to concentrate the most motile sperm for injection into the uterus near the fallopian tubes. This aims to increase the number of motile sperm cells that reach the eggs and subsequently increase the chances of fertilization.

History of IUI

The history of intrauterine insemination (IUI) in animals dates back to the 14th century when Arabs used it to breed stallions. The technique was further developed in the 18th and 19th centuries and is now widely used in farming, livestock breeding, and rare animal conservation.

Here are some other milestones in the history of artificial insemination:

• 1678 : Antoni van Leeuwenhoek and his assistant Johannes Ham first described and observed spermatozoa in the Netherlands.

• 1780 : Italian physiologist Lazzaro Spallanzani reported the intrauterine insemination (IUI) in a dog.

• 1790 : Scottish surgeon John Hunter successfully impregnated a woman with her husband’s semen, the first recorded instance of intrauterine insemination (IUI) in humans.

• 1922: Ilya Ivanovich Ivanov developed the methods of artificial insemination that are used today.

• 1945 : The first reports of donor insemination were published in the British Medical Journal.

• 1953 : Dr. Jerome K. Sherman introduced a simple method for preserving human sperm using glycerol. He also reported the first successful human pregnancy with frozen sperm.

• 1955 : Four successful pregnancies using previously frozen sperm were reported.

• 1978 : IVF development leads to improved sperm-washing techniques. These techniques remove prostaglandins,

  infectious agents, and antigenic proteins, and can also remove nonmotile sperm. The result is sperm with better fertilizing ability, which made AI a popular treatment for mild to moderate male infertility

• 1995 : The first pregnancy reports from spermatids and oocyte activation were published.

• 1995 : Dmitri Dozortsev and colleagues discovered that a sperm factor triggers oocyte activation during

  intracytoplasmic injection (ICSI).

• 1995 : Zenzes from the Casper group in Toronto demonstrated that cigarette smoking can negatively affect the nuclear spindle.

Other milestones in the history of AI include:

• The first successful AI in a dog was in 1780

• The development of semen extenders

• The addition of antibiotics to semen

• The discovery that glycerol protects sperm during cryopreservation in 1949

• The establishment of the first AI cooperative in Denmark in 1936

• The establishment of the first AI cooperative in the United States in 1938

What is Sperm Washing ?

Prior to the process of IUI, a sperm sample is collected and washed. The sperm wash involves removing the extra fluid, eliminating the dead sperms, weak sperms, bacteria, debris, and prostaglandins that can cause uterine cramps, at the same time concentrating the most motile sperms in order to ensure that a larger number of motile sperm cells reach the uterus.

Washing is the first step of preparation of sperm sample for IUI. It involves separation of the sperm cells from the seminal fluid.

This process, in addition to removing toxins, also increases the chances of the sperm reaching the fallopian tubes by increasing its fertilizing capacity. Hence it can also aid couples with unexplained infertility or immune system disorders.

How IUI Works

To understand how IUI works, it helps to know what happens during a typical conception.

Following ejaculation, sperm moves up the vagina and into the cervix, which is the opening to the uterus. After navigating through the cervix, the sperm move into the uterine cavity and then the fallopian tubes. These are a pair of tubes that capture the egg after it releases from the ovary.

If sperm are in the fallopian tube when the egg arrives, the egg and sperm can meet. The egg can undergo fertilization and become an embryo. The embryo then travels back through the fallopian tube and into the uterus, where it implants to become a pregnancy.

The cervix is a natural barrier to sperm movement. This means that after ejaculation, only a small percentage of sperm can move past the cervix and into the uterus.

An IUI procedure sidesteps this issue by inserting the sperm past the cervix and into the uterus. This shortens the distance the sperm travels to reach the fallopian tubes, increasing the likelihood that one sperm will meet and fertilize the egg.

IUI procedure step by step

The IUI procedure consists of the following steps:

1. Sperm collection: This can happen in several ways, such as through:

• masturbating into a sterile container

• retrieving into a special condom during sex

• extracting from a urine sample in a lab

• collecting while undergoing vibratory stimulation

2. Sperm sample washing: This involves the removal of the seminal fluid from the sample because it can cause severe cramping in the female. This part can take 1–2 hours.

3. Sperm insertion: The individual will lie down as a healthcare professional inserts a thin, flexible catheter through the cervix into the uterus. They then slowly inject the sperm sample. This takes a few minutes.

When is IUI Recommended?

IUI is often recommended for couples with :

• Male infertility :

  Low sperm count, poor sperm motility, or other sperm-related issues.

• Unexplained infertility :

  When no specific cause of infertility can be identified.

• Cervical factors :

  Cervical mucus abnormalities that may hinder sperm passage.

• Endometriosis :

  A condition where tissue similar to the uterine lining grows outside the uterus.

Success Rates of IUI

The success rates of IUI vary depending on several factors, including the age of the woman, the cause of infertility, and the number of IUI cycles attempted. Generally, the success rates of IUI are lower than those of in vitro fertilization (IVF). However, IUI can be a good option for couples with mild infertility issues.

Advantages and Disadvantages of IUI

Advantages of IUI treatment

Even though the success rate of IUI is lower than IVF, here are some of the benefits of proceeding with the IUI treatment.

1. Less stress on the body. IUI offers gentler conditions than other treatments like IVF, which can be harsh and aggressive and affect egg quality.

2. Compared to regular sex, IUI treatment increases the chances of successful conception. Unlike regular sex, where only the strongest sperm can make it to the cervical mucus and then to the uterus and fallopian tubes, IUI helps the sperm fast-track straight to the egg for fertilization.

3. Ovarian Hyperstimulation Syndrome (OHSS) is less common.

4. IUI follows a natural cycle and is less invasive on the body and uterus than treatments like IVF.

5. IUI is a beneficial way to understand how the body will react before directly going for treatments like IVF. Also, it can help not to waste a cycle.

Some of the factors influencing IUI success include primary or secondary subfertility, the duration of subfertility, endometriosis, and the use or non-usage of ovarian hyperstimulation.

Disadvantages IUI

Even though IUI is a beneficial option for most couples, it does not address all the fertility challenges at times. The following list includes some of the disadvantages of IUI treatments:

1. A high degree of intervention can occur if the following factors are not met:

• Clear and undamaged fallopian tubes

• The partner should be ovulating during the pregnancy test.

• Sperm should have a certain level of motility.

2. Compared to other treatments like IVF, the chances of getting pregnant are lower with IUI. The success rate is between 15% to 20 %.

3. The risk of multiples, i.e., having twins, triplets, or more, is much higher, as there is little control over how many eggs will develop, and it is difficult to guarantee how many will fertilize.

So,

IUI is a valuable option for couples facing infertility challenges. By understanding the IUI process and working closely with a fertility specialist, couples can increase their chances of achieving pregnancy.