IVF drugs are used to produce several eggs during one cycle.

 

Single cycle IVF

Stimulation of the Ovaries

Drug regimes can be tailored to the needs of the patient. The most commonly used regime is the "long protocol". Following a baseline scan, treatment begins with the use of gonadotrophin releasing hormone (Gn RH) analogue which is given either as a daily subcutaneous injection (Buserelin) or as a nasal spray (Synarel).

The analogue stimulates and then suppresses the activity of a small gland in the brain, known as the pituitary, which normally controls the natural release of two important hormones - follicle stimulating hormone (FSH) and luteinising hormone (LH). This is known as pituitary desensitisation or "down regulation ". Down regulation, which can take up to fourteen days to achieve and is confirmed by ultrasound, is followed by daily injections of gonadotrophins to simulate the ovaries. Both Gn RH analogue and gonadotrophins are given until the follicles reach optimum size.

Human Chorionic gonadotrophin (HCG) is a hormone with an LH-like action. It is given by injection 35 to 36 hours before egg collection to ensure adequate ripening of the eggs within the follicles. The timing of this injection is very important.

Collecting the Eggs

Eggs are collected using ultrasound guidance under intravenous sedation. The ultrasound probe is introduced into the vagina, ovaries are visualised and a hollow needle is guided through the top of the vagina into each follicle. The fluid within the follicle is aspirated and examined in our laboratory for the presence of eggs. In exceptional cases, where the ovaries prove to be inaccessible vaginally, the procedure may be performed through the abdominal wall under local anaesthetic using ultrasound guidance. Alternatively, egg collection can be performed under general anaesthetic in a hospital setting. Ultrasound-guided egg collection takes between twenty to forty minutes, and generally results in about five to fifteen eggs being collected.

Sperm Collection

The male partner will be asked to produce a semen sample on the morning of egg collection, and for this purpose should abstain from intercourse for about three days prior to egg collection.

Fertilising the Eggs

After egg collection, the eggs are incubated for a short time and then about 100,000 motile sperm from the prepared sample are added to each egg and incubated for a further 24 hours. The presence of pronuclei within the egg is the first indication of fertilisation

Embryo Transfer

Embryos are generally transferred two or three days after egg collection. Blastocyst transfer takes place five or six days after egg collection. No anaesthetic is required for embryo transfer. The procedure is similar to a smear test.

The most suitable embryos are selected for transfer. They are loaded into a thin plastic tube, the embryo catheter, which is passed through the cervical canal and into the uterus where the embryos are injected.

In accordance with the Human Fertilisation and Embryology Act, a maximum of two embryos can be transferred in any cycle. High quality embryos remaining after the transfer may be frozen for use at a later date.

Progesterone pessaries are administered after embryo transfer. If you do not have a normal period, a pregnancy test is performed approximately fourteen days after embryo transfer. If your test is positive, an ultrasound scan is performed two weeks later to confirm that the pregnancy is in the uterus and that it is progressing normally.

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