What are IVF and ICSI?

IVF and ICSI are two quality laboratory techniques that are used to fertilize the egg with the partner sperm or donor sperm. The harvesting of eggs is done from the ovaries in a natural cycle or with the use of hormones in controlled ovarian stimulation. Special incubators are used to keep the fertilized eggs to develop them into embryos. These embryos are then transferred to the uterus on day 2 or 3 of development (known as cleavage stage) or more preferably on day 5 or 6 (known as blastocyst stage).

Steps for IVF and ICSI

The treatment cycle of IVF and ICSI has the following steps:

  • Prescribing hormone medications that help grow multiple follicles in order to collect multiple eggs.
  • Conducting ultrasound scans and blood tests to check ovarian response.
  • Administering trigger hormone injection 34 to 36 hours before retrieving the eggs.
  • Using ultrasound guidance and sedation in an operation theater to retrieve eggs from the ovaries.
  • Using IVF or ICSI to fertilize the eggs with sperm in a laboratory.
  • Developing the fertilized egg to embryos in the laboratory.
  • Transferring one or more embryos to the uterus in the operation theater. Sedation is usually not required for this process.
  • Taking hormone medications as instructed while you wait for the pregnancy test.
personalised treatment

Difference between IVF and ICSI

During IVF, the eggs and sperm are left to fertilize on their own in the laboratory while placed in a plastic dish within an incubator. It is not possible to determine whether the eggs have matured or not because they are not stripped of their surrounding cells. During ICSI, the egg is directly injected with the selected sperm. Each sperm is individually checked for maturity by removing the cells around the sperm before the injection. The sperm is only injected in the mature eggs. Inseminated and injected eggs are both placed in the incubator in the laboratory after the process till the next day. After this the embryologist checks the eggs for signs of fertilization.

Frequently asked questions

Ovarian stimulation is usually recommended to collect multiple eggs in most cases. Hormone injections containing follicles stimulating hormone (FSH) are required for the simulation with or without luteinising hormone (LH). These injections are generally started at the very beginning of the menstrual cycle or during an induced bleed. The type of hormone and the dose is specific to each patient. It depends on various factors such as age, body mass index, anti-Mullerian hormone (AMH) levels, antral follicle count (AFC) and response to previous ovarian stimulations if available from your medical history.

You must administer the injections yourself everyday at the same time. Depending on the ovarian response the injections are to be administered for 10 to 14 days. Your expert consultant will prescribe the trigger injection when your follicles have reached their optimal size to ensure the eggs within your follicles mature and are ready to be harvested 34 to 36 hours later.

Five or six days after taking the hormone injections you will undergo transvaginal scans every 2 or 3 days. This is important as it helps in determining the development of follicles, to alter the dose of the medicines if required to ensure adequate response and to decide when to administer the “trigger” injection for egg retrieval. Sometimes blood tests are also required along with the scans to better understand the response to ovarian stimulation.

Egg collection is performed in the operation theater close to the laboratory. Sedation medication will be administered to you through an intravenous line. Nursing staff and an anesthetist will be present with you along with the expert consultant. Pain relief may be given during or after the procedure if required.

Based on the number of follicles and the difficulty to access the ovaries this process can take 15- 30 minutes. The fluid of each follicle is extracted into a clear tube by a fine needle which is inserted through the vagina into the ovaries by sliding into a guide mounted on the transvaginal scan probe. This fluid is then passed to the embryologist who checks for the eggs. Very rarely, if there is a small area of bleeding, absorbable stitches may be put inside the vagina. Normal activities can be resumed the next day.

The sperm to be used for insemination is either received fresh from your partner on the day of egg collection or, if it has been frozen, it is thawed and prepared to be made ready for insemination. In case of donor sperm, it is thawed and processed on the day of egg retrieval.

Once the eggs are checked for fertilization, the embryologist inspects the development of embryos over the next few days directly or by means of time lapse technology. To help their development process the embryos are placed in special culture media solutions in controlled incubators.

The steps from fertilization to blastocyst formation are as follows:

Day 1: The inseminated or injected eggs are checked for fertilization.

Day 2: The fertilized eggs start to become embryos by dividing into multiple cells. They usually have 2 to 4 cells at this stage.

Day 3: At this stage the embryos have developed further and have 6 to 8 cells. They may be chosen for transfer now or left in the culture solution to develop further.

Day 4: Known as Morula stage. No evaluation of embryos is done at this stage but time lapse systems can be used to gain information.

Day 5: Known as blastocyst stage. The embryos can now be transferred if planning a fresh embryo transfer or can be frozen for future use. The embryos which have not reached blastocyst stage are left in the culture media for longer to be frozen later the same day or on day 6.

No anesthesia is required for this process unless it has been difficult for you in the past or if you prefer to have it. The embryologist will select the best embryo(s) for transfer. The process is carried out in a dedicated procedure room. Mild discomfort may be experienced by some women. The practitioner cleans the vagina by inserting a speculum in the vagina. After that a catheter is inserted through the cervix into the uterus to place the embryo(s) under ultrasound guidance. You are required to have a full bladder.

Women may experience some light cramping and very occasionally spotting and vaginal discharge after the cramping. You are advised to take it easy and avoid hot baths, saunas, exercise, sexual intercourse, swimming, steam rooms, drinking alcohol and smoking. Be sure to take your supplements and folic acid as recommended by your expert consultant and follow the instructions given by your fertility team if taking hormones. Depending on whether you had blastocyst or cleavage stage transfer, your pregnancy test will be scheduled for 12-15 days after the embryo transfer.

IVF and ICSI have both been practiced for around three decades and more than 2.5 million treatments are performed worldwide every year. There is published literary data showing that the rate of success as clinical pregnancy or live birth depend on many factors like number and quality of eggs, chronological age of the female, quality sperm, quality of embryos, previous pregnancies as well as lifestyle. Still, the birth rates in good prognosis patients can be as high as 50-55%. With no difference between frozen and fresh embryo transfer.