IVF and ICSI: What is the difference?

ICSI stands for intracytoplasmic sperm injection. This special method of artificial insemination involves the direct fertilisation of an egg cell in a laboratory using a selected sperm cell. ICSI treatments are carried out if the man’s sperm demonstrates reduced quality or limited mobility, or if there is a limited number of sperm available.

Conventional in vitro fertilisation (IVF) involves mixing the egg cell with tens of thousands of sperm cells in a test tube. If the sperm quality is insufficient, or if not enough sperm cells are produced, a conventional IVF procedure does not have a good chance of being successful – however this is not the case with intracytoplasmic sperm injection. The advantage of the ICSI treatment method is that it only requires a few sperm cells. In a laboratory, a single sperm cell is selected and then directly injected into the egg’s cellular fluid using a microinjector. The egg cell is thereby fertilised using one specially chosen sperm cell. In 2015, 81 % of all IVF cycles in Switzerland were performed using ICSI and this trend is increasing.

The doctors and medical experts at Hirslanden have decades of experience in the provision of IVF and ICSI treatments and are specially trained to accommodate the different cultural requirements and expectations of our international patients.


How is ICSI done? An ICSI treatment is similar to conventional IVF: after a comprehensive consultation, your Hirslanden doctor will test the man’s sperm quality and organise hormonal treatment for the woman. This treatment prevents premature ovulation and stimulates the ovaries to mature several ovarian follicles at the same time. At regular check-ups over the next two weeks, your doctor will examine the maturity of the egg cells and decide whether it’s time to trigger ovulation. If the egg cells are ready, the doctor will remove them from the ovaries. This outpatient procedure is performed at your Hirslanden doctor’s medical practice and you will be able to leave the clinic on the same day.

On the day of the procedure, the man provides a semen sample. The most suitable sperm cells are chosen and prepared using various methods, such as physiological sperm selection. Now the intracytoplasmic sperm injection (ICSI) is done by injecting each sperm cell directly into the cellular fluid of an egg – this part of the treatment represents the main difference between IVF and ICSI. The fertilised egg cells are then observed over a period of three to five days as they develop into embryos.  Following this, your Hirslanden doctor will transfer one or two of the embryos into the woman’s womb (embryo transfer). If some of the other embryos have also developed well, on request they can be frozen in liquid nitrogen and stored at the laboratory, so that they will be available if further treatments are necessary or desired.

Genetic testing

In September 2017 Switzerland passed a law allowing embryos to be genetically tested before they are implanted inside the woman (pre-implantation genetic diagnosis). These tests significantly reduce the risk of the treatment failing, as well as the risk of miscarriages and twin pregnancies. Genetic testing is particularly relevant for women over 38 and couples who have previously failed to conceive artificially or experienced miscarriages.

Success rate

How successful is ICSI? If the sperm quality is normal, the rate of falling pregnant with ICSI is similar to conventional IVF. However ICSI makes it possible to avoid situations where none of the egg cells are fertilised, even though the sperm results were normal – which can happen with conventional IVF. If the man has reduced fertility or if previous IVF treatments have been unsuccessful, couples should definitely opt for the ICSI method.

In 2015 the Hirslanden specialists at our Gyné invitro laboratory achieved a pregnancy rate of 50.4%, which was the best result nationwide according to anonymous Swiss statistics. Your Hirslanden doctor will gladly discuss your wishes and expectations with you and provide expert advice.


Artificial insemination does not automatically result in pregnancy and an inability to conceive can place emotional strain on couples. For this reason, your Hirslanden doctor will meet with you and your partner prior to any treatment to discuss any fears, worries and expectations you may have, and to clearly explain the various stages involved.

The extraction of the egg cells requires a small outpatient procedure performed under a brief anaesthesia. Risks related to the brief anaesthesia and the possible puncturing of egg cells are rare, but need to be taken into consideration.


The following requirements must be met before an IVF or ICSI treatment can be carried out:

  • Availability of basic data (hormonal analysis of the woman, ultrasound examination, semen sample)
  • The maximum age for women is between 42-44, the maximum age for men is between 60-65
  • Stable relationship (the couple does not have to be married)
  • Both partners must be HIV negative
  • The woman must be immune to the rubella virus (either through having had the disease or vaccination)
  • A selection of embryos according to sex or physical characteristics is prohibited by law in Switzerland.