IVF versus ICSI success rates

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For couples who are experiencing problems conceiving the stress can, at times, become almost unbearable, often putting an incredible strain on a relationship. Sadly, many couples don’t seek the help they need and what may be a relatively minor complication remains unresolved. For most, a trip to a fertility clinic will result in recommendations regarding lifestyle or some relatively minor treatment. However, in some instances, doctors may suggest that the couple undergo more extensive fertility treatment such as IVF, ICSI or a combination of the two.

As the top fertility clinic in Thailand, we offer IVF and ICSI treatments to patients in the comfort of our state of the art clinic. Of course, patients will undergo a thorough investigation into their needs with all options discussed and recommendations made by our expert team of doctors. One of the most frequent questions that we get asked is regarding success rates, and we always give honest and transparent answers explaining that there are many factors influencing success rates, but we can give them an overall figure.

Is IVF or ICSI more successful?

Overall, the success rates for IVF and ICSI are very similar, although the techniques are often used to treat different conditions. Where the problem is connected to male infertility such as a low sperm count or low motility, ICSI (Intracytoplasmic Sperm Injection) or a combination of ICSI and IVF (In Vitro Fertilisation) has been proven to be the most successful Assisted Reproductive Technique (ART).

For many clinics, ourselves included, ICSI is commonly used in combination with IVF as it will lead to higher rates of fertilisation. However, it should be stressed that this doesn’t necessarily equate to a greater chance of becoming pregnant. The cost of using both techniques is the same as with standalone IVF treatment.

A brief overview of IVF treatment

IVF treatment involves collecting and combining the female’s eggs and the male’s sperm in controlled laboratory conditions and is where the term “test-tube baby” originates from. The female is given a combination of drugs to stimulate egg production artificially, and the eggs are harvested in the fertility clinic at the optimal time deemed by the doctors. Once the eggs are collected, the male will make a sperm donation, and the egg and sperm are combined with fertilisation occurring naturally. Some of the fertilised embryos are then transferred back to the female’s womb, hoping a normal pregnancy will follow.

Who is suitable for IVF treatment?

IVF is the number one treatment offered to females experiencing fertility issues after the age of 40. It is most commonly recommended when the female is experiencing fertility problems rather than the male partner. A number of health issues often result in the IVF being presented as an option by your doctor. Some of these conditions may include damage to or a blockage in the fallopian tubes; if the female suffers from an ovulation disorder, endometriosis, if she has uterine fibroids or has previously undergone sterilisation.

It can also be recommended for fertility preservation, where one partner may be suffering from cancer and require chemotherapy or radiotherapy. In these cases, eggs can be fertilised at the time and be frozen. The process of freezing eggs or embryos is also sometimes considered by females who feel that they are not ready to conceive but are aware that their body clock is ticking. Some doctors recommend IVF treatment where infertility can’t be explained or when there are issues with the male’s sperm. However, in these cases, ICSI either on its own or combined with IVF may be a more appropriate route.

A brief overview of ICSI treatment

During ICSI treatment, eggs and sperm are collected in the same way with drugs being administered to the female to stimulate egg production and sperm being collected, usually via masturbation. In some circumstances where the male’s sperm count is exceptionally low, the sperm may be taken directly from the testes via a small needle under a local anaesthetic. The significant difference between the two techniques is that an embryologist will directly inject sperm into each egg rather than fertilise it naturally. It reduces any problem that may have been otherwise caused due to small quantities of sperm or low mobility.

 Who is most suited to ICSI treatment?

Although ICSI treatment is suitable for all couples, it is mostly recommended for couples who have issues relating the sperm quality and/or quantity. Medically, the conditions would typically be referred to as a low sperm count, poor morphology where a high percentage of the sperm are abnormally shaped, azoospermia where no sperm is present in the semen or low motility where there are issues with the sperm’s movement.

ICSI is also recommended for male patients who have had a vasectomy or vasectomy reversal has failed. If sperm also needs to be removed by surgical processes such as TESE or PESA, ICSI would be recommended by the doctor as it will lead to more eggs becoming fertilised. Should chromosome screening to required, ICSI would need to be used to reduce the likelihood of any abnormalities.

Combining the treatments

There is an increased call for IVF and ICSI to be combined in all cases to increase the number of eggs that become fertilised. There are many reasons for this. It gives doctors the opportunity to select the highest quality embryos from a larger pool. It will also mean that it almost eliminates the chance that no eggs will become fertilised. As the cost is the same, it would be viewed as being in the couple’s best interests as it could potentially increase their chances of becoming pregnant.


Both IVF and ICSI enjoy relatively high success rates with little difference between the techniques when used separately. It does make a difference when there are male fertility problems when ICSI has significantly higher success rates. ICSI leads to higher fertility rates but not necessarily higher pregnancy rates where age, embryo quality, and the womb condition will all play a role in determining the treatment’s success.