Factors Affecting the success rates of IUI

IUI is an ART procedure with a modest and variable success rates of 5 to 25 % per cycle.

Here comes the importance of knowing what our couple who are offered IUI can do to achieve their optimal result.

When it comes to measures to improve the success, the knowledge that many factors are determined by them in itself makes the process easy.

BMI overweight and obesity is associated with subfertility in both men and women. In

women it causes irregular cycles and absent menses, higher doses of injections to achieve the follicle formation, prolonged duration of treatment, suboptimal follicle development and in men it causes impaired semen qualities like lower semen volume, decreased sperm concentration, reduced TMSC and abnormal morphology. Impaired endocrine function and insulin resistance is seen with elevated BMI. Excess body weight will affect both natural conception and ART conceptions such as IUI.

Nutritional Diet rich in PUFA, folate, fibre, starch and adherence to mediterranean style diet. Several micronutrients Zn, Se, vitamins B12 A E and C trace elements like Ni Mn are critical for optimal spermatogenesis. Arginine an amino acid needed for sperm count and motility

Habitutations abstinence from tobacco use (smoking or chewed forms both active and passive use) and alcohol prior to and throughout the treatment is necessary. The success rate of IUI treatment is reduced by the smoking as these couples tend to require a higher dose of medications and there will toxic effects of the tobacco chemicals on follicular development and abnormal sperm and egg formation, reduction in egg numbers and increased miscarriages.

Anxiety: Fertility problems negatively affect psychological well-being. Some of the drugs in itself can contribute to the already existing symptoms. It can produce the immune dysregulation and inflammatory activation in the body

Partially modifiable factors

Environmental exposure to toxins, radiation, heat, air borne pollutants certain chemical agents

Non-Modifiable factors

Age of women

strongest predictor of IUI success and ASRM guidelines indicate that IUI effectiveness is significantly limited in women over 40 years

Male age increasing paternal age above 40 years can lead to premature birth, abortions, autism

spectrum disorders and infertility. There are more of sperm abnormalities after the age of 50. Advanced

age is associated with sperm DNA fragmentation also.

How can we doctors help our couples to achieve their maximum success rates

Male factors

Sperm preparation

Your doctor will know the best method that suits the preparation of your semen for IUI according to the

nature of the semen parameters. Some of the factors that hamper the quality of the semen parameters

would be an improper transport condition and prolonged interval between the sample collection and

the sample processing then processed sample to the insemination procedure. To avoid these problems,

it’s always better to collect your sample in the IUI facility itself. Fresh ejaculate is better as frozen semen

sample is associated with reduced motility and viability as result of the cryodamage.

Semen volume and sperm count

Total progressive motile sperm count (TMSC) demonstrates the strongest association with IUI success.

Post wash TMSC >=10 million is the threshold for an optimal IUI success. The chance of achieving

pregnancy diminishes when TMSC falls below 5 million especially among women with prolonged

infertility exceeding 10 years. When the TMSC is persistently low and pregnancy is not achieved couples

need to think about transition to alternative ART options.

Sperm morphology  

Abnormal sperm morphology is associated with higher miscarriage rate around 35.6%

Sperm DNA fragmentation

Failure to achieve pregnancy after >=2-3 well conducted IUI cycles ie with adequate ovarian stimulation

and satisfactory TMSC we need to assess sperm DNA fragmentation. The pregnancy loss is 27.3% with

high sperm DNA fragmentation. Addressing the modifiable factors would largely help in reducing the

DNA fragmentation in addition to treating infections optimizing comorbid diseases and frequent

ejaculations.

Maternal factors

Number of follicles

The more the number of follicles higher is the IUI success. Multi-follicular development is achieved with

the use of specific treatments albeit they come with a risk of higher order pregnancies

Endometrial thickness

The lining of the uterus below 6 mm is associated with reduced pregnancy rates. Diet enriched with

vitamin E and arginine will help with the endometrial blood supply

Luteal support

Vaginal progesterone gel or micronized progesterone significantly increases the clinical pregnancy rates

and live birth rate especially when injections are used to stimulate the ovaries for follicle development

Given the above information the ultimate success will depend on the personalised treatment

approaches wherein IUI should be indicated as per the cause of infertility which your doctor will be able

to determine.