Medical fertility treatments

The process of Intra-Cytoplasmic Sperm Injection, i.e. injecting a single sperm directly into the egg, as a means of achieving fertilisation and subsequent pregnancy, has been increasingly used in fertility clinics now for almost 15 years, and has resulted in the birth of thousands of healthy children that would not otherwise have been conceived. ICSI is now performed in over a third of couples having IVF. The most common indication for this extra laboratory procedure is a low sperm count, or poor sperm motility, but it is also used when a small number of eggs have been collected, when anti-sperm antibodies are present in semen, when a couple are also having PGD or PGS, or when fertilisation has been poor with routine IVF. Only a small number of healthy looking sperm are required in total; only one sperm per egg compared with 200,000 sperm per egg for routine IVF, and the outcome in terms of fertilisation rates and pregnancy rates is similar to IVF. The ICSI procedure itself is very delicate, and requires specific laboratory training, but it does not appear to damage the egg in any way. There is no association with miscarriage, and despite concern about the impact of this relatively invasive procedure on normal pregnancy development, there is no conclusive evidence that it increases fetal abnormalities in the offspring, however the development of children conceived using ICSI continues to be monitored world wide.

Men with very poor sperm whose partners require ICSI to achieve pregnancy, may pass on the genetic tendency to have poor sperm production to their sons. This rarely influences a couples’ decision to proceed with treatment, as the use of donor sperm is the only alternative in these cases, and the sons hopefully would be able to benefit from continued improvements in fertility treatment when they try to start a family themselves.

Embryo freezing (cryopreservation) has been routinely used in fertility clinics since the early 1990s. Spare embryos may be kept and used for further treatments when the first cycle fails, or if it is successful, and a couple wish to have more children in the future.

Most clinics will only consider freezing good quality embryos, as these are the ones most likely to survive the freezing process. On average 50-75% of embryos frozen will still have developmental potential when thawed.

Embryos do not deteriorate in storage and can be safely frozen for up to 10 years, although most couples use spare embryos (or decide to donate them to another couple, for research, or have them destroyed) within 5 years.

The majority of embryos are frozen on the day of embryo transfer, when they are 2-3 days old. Sometimes embryos are frozen on the first day after fertilisation. These embryos are smaller, and more likely to withstand the freezing process. Patients who are having blastocyst culture may freeze spare blastocysts, but these tend not to freeze so well because they are bigger 5 day old embryos. This has prompted the development of a relatively new clinical technique called vitrification which basically means that instead of being frozen, the embryos are converted into a glass like state, still suspended in time, but without the risk of ice crystal formation, which destroys embryos. Clinics are increasingly recommending vitrification for embryo preservation as an alternative to freezing, especially for more advanced embryos.

The babies born after a frozen embryo cycle are completely normal. There are no links to increased miscarriage or abnormality rates, but even if a frozen embryo survives the thawing process, the chance of implantation is still a little lower than that of a fresh embryo. The advantage of having frozen embryos is that a cycle is considerably cheaper, less stressful and less invasive than a fresh IVF attempt.

A blastocyst is the term given to an embryo that has been growing for 4-6 days, and has reached the stage when it is ready to ‘hatch’ out of its’ protective shell, much like a chick does from a hen egg, and hopefully implant in the wall of the womb and continue to grow. The transfer of 2 embryos that have been strong enough and healthy enough to reach this stage of development outside the body, is 10-15% more likely to result in a pregnancy when compared with the transfer of 2 embryos at an earlier developmental stage. In addition to enabling selection of the healthiest embryos to transfer, the other theoretical advantage of replacing blastocysts is that this would be the stage when the embryo would naturally just be entering the womb, having spent the earlier stages of development moving slowly down the fallopian tube.

Only women who have 6 embryos or more on the day after egg collection would normally be considered as candidates for blastocyst culture. The chance of pregnancy is similar if one blastocyst is transferred when compared with two day 2 embryos, and obviously the risk of twins is virtually eradicated with the former approach.

There is an additional charge for blastocyst culture but Miss Matthews would recommend it for any suitable couples as a fantastic way to improve the chance of pregnancy in a treatment cycle.

Assisted hatching may be associated with an increased pregnancy rate in selected patients. The technique was very popular in the late 1990s, but fell out of favour simply because evidence of benefit was not convincing. It is a technique still offered by most fertility clinics, but only to selected patients. Assisted hatching involves the creation of a small hole in the embryo shell (zona) with a laser, or a chemical process which thins and weakens the zona, just before the embryo is transferred into the womb. It is useful for women whose embryos have been identified as having a zona that appears particularly thick, or is suspected of being harder than normal. The zona is very important for holding the embryo together in the early stages, but in order for the embryo to develop beyond the fifth day, it must ‘hatch’ out of the zona, at which stage it continues to expand and grow as it hopefully imbeds and implants in the womb wall. This process may be hindered if the zona is too hard or too thick.

Pre-implantation genetic diagnosis (PGD) offers a means of pre-pregnancy screening for a specific genetic problem which has a high risk of being passed on to the children of affected parents, or when the parents carry the gene for that specific disease. It offers an alternative to prenatal testing in early pregnancy and the abortion of a affected fetus.

Embryos that result from IVF treatment can be screened for some common genetic problems (including Downs Syndrome) before they are placed inside the womb cavity. The aim of PGS is to replace 1-3 ‘normal’ embryos and thus improve the chance of conception, and reduce the risk of miscarriage for a couple having fertility treatment. This form of screening does not guarantee a healthy pregnancy. Implantation of the normal embryo(s) may not occur, and only a few potential problems are eliminated. It may be considered however for couples with repeated failed treatment, older women, or those with a history of miscarriage.

It is my routine practice to offer the services of a specialist fertility counsellor to all patients who are considering formal fertility treatment, and indeed it is legally required before certain types of treatment, including the use of donor sperm or eggs, and surrogacy.

Infertility in itself can be associated with feelings of helplessness and often despair. It can impact on every aspect of a couples’ relationship, their relationship with friends and family and their work. The stress and gradual erosion of self confidence can be devastating, as can the additive impact of repeated failed fertility treatments. Counselling can provide an opportunity to air concerns, help yourself and your partner to find coping mechanisms and resolve relationship issues, and to deal with crises and longer term grieving. It is more often used as a platform to discuss the potential psychological, moral and ethical implications of fertility treatment and to prepare patients for what may lie ahead.

The counsellor I most often refer to is Jacqui Feld, whose profile and contact details can be found in the ‘links’ section of the website. Jacqui is one of the most experienced fertility counsellors in the UK and highly respected by clinicians and her peers in the field.