Intra Cytoplasmic Sperm Injection (ICSI)
ICSI is done if the number or quality of the sperm is poor so that there is a query as to whether fertilisation will take by simply mixing the eggs and sperm together. Although this is an unnatural way of fertilising eggs, it provides the only way that a man with poor quality or numbers of sperm will ever father a child.
Concerns have been raised as to the long term consequences of ICSI on any children born. Although there is certainly evidence that some men have a variation in their male y chromosome that makes them subfertile and that this will be passed on to their sons along with the rest of their male characteristics; there is no evidence in any identifiable significant increase in abnormal children conceived by this method.
ICSI started in 1992, i.e. is now over 15 years old so any major complications would have shown up by now. Indeed with the loss of anonymous donors in the UK, and the extreme shortage as a consequence of men prepared to donate sperm, ICSI combined with surgical sperm retrieval ( a technique where sperm is extracted either with a needle or by a biopsy of the testicle under anaesthetic, if none is found in the semen) is the only way these men will ever have children in their relationship.
Embryo Transfer is done on either the second, third, fourth or fifth day post egg collection. The best chances of being pregnant are if the embryos are put pack on day 5. That is when they are a ball of cells called a blastocyst, just before they implant into the lining of the womb. The benefit of blastocysts is that they have reached an advanced stage of embryo development in an artificial culture environment and are therefore highly likely to continue growing once they are back inside the womb. The problem is that by no means all embryos will reach the blastocyst stage of development and as such the risk of growing them for 5 days rather than 2 is that they may be no embryos to put back. In practice if only 2 embryos are available on day 2 then no further selection is possible and they may as well be put back into the natural environment as soon as possible. If there are 10 or more good quality embryos on day 2 then growing them till day 5 aids a more accurate determination of the best embryos on day 5.
Embryo Transfer takes place with a full bladder and ultrasound control, so that the most accurate position of the embryos inside the womb is achieved. The procedure is similar to having a cervical smear. A speculum is placed inside the vagina, the cervix is visualized, gently cleaned with a swab soaked in the embryo culture medium to make sure that the environment is not contaminated with cervical mucus. A small catheter is then gently inserted through the cervix and into the womb. Whilst performing a scan by placing an abdominal probe over the full urinary bladder then the position of the catheter can be visualized. The optimal place is about 1 cm short of the top of the womb. A few drops of the culture medium is injected with 2 embryos for a woman up to the age of 40 or 3 embryos for woman over 40 years old.
The environment for the embryos to grow is improved by the addition of natural Progesterone (a pessary Cyclogest given twice a day or a vaginal gel Crinone given once a day). The addition of low dose Aspirin 75mg per day not the 300mg tablet will increase the blood supply to the womb by preventing the blood sludging. There is also evidence that this dose of aspirin taken till 14 weeks pregnant will also reduce the risk of miscarriage.
A pregnancy test is done 2 weeks after the embryos have been replaced. This can be either by the first morning urine sample at home, or by a blood test in the clinic. Once pregnant the Progesterone is usually continued to reduce the risk of miscarriage till 14 weeks.
There is no evidence that an IVF pregnancy is any more risky than a natural conception apart from the fact that there is an increased chance of a multiple pregnancy. Most women can carry a single baby or twins to near full term (40 weeks) without too much problem. However there is less space if 2 or more babies are growing. This means that they tend to be born progressively earlier with each additional baby, with the possibility that they will require help in a special care baby unit. Severely premature babies are at increased risk of problems with their brain development. As a result of this the embryos put back are usually limited to 2 to reduce the chance of a multiple pregnancy and the pregnancies are carefully monitored. The author personally looks after the pregnant women up to and including their birth if the couple wish.