03.Assisted reproductive technology
Assisted reproductive technology (ART) refers to the application of laboratory or clinical technology to sperm, eggs and / or embryos (fertilised eggs) to assist the conception of a baby. About 10 to 20% of couples with diagnosed infertility are offered ART. These advanced and complex treatments have had improving success rates in recent years but the chances of a successful pregnancy and giving birth to a baby are still relatively low.
The success of ART depends on many factors such as the diagnosed fertility problem, the type of technology used, the fertility clinic or specialist themselves, if the embryos (fertilised eggs) are fresh or frozen (have been stored) and the age of the woman.
As a guide, the general success of ART resulting in the birth of a live baby for women under 35 years is around 25%, for women from 35 to 39 it is around 18% and for women aged 40 to 44 it is around 6%.
Egg and Sperm Collection
Accepting ART treatments means the woman's eggs and the man's sperm need to be artificially collected. For the man this may just mean providing semen in a jar provided by the clinic up to an hour or two prior to it being required for use, or it could mean sperm retrieval through surgery. For the woman it means taking medications to stimulate follicle or egg development and ovulation and then having her eggs surgically removed from her ovaries, called egg collection or egg pickup - EPU.
Egg collection is usually done by the fertility specialist passing a needle through the top of the woman's vagina near her cervix, guided by ultrasound to retrieve the eggs (called trans-vaginal oocyte retrieval or OCR).
Generally local anaesthetic is recommended, perhaps with light sedation, so the woman can watch her eggs being retrieved on a TV monitor and her partner can be with her during the procedure. However, a general anaesthetic can sometimes be used if preferred.
Some women experience cramping for a few days after egg collection, which can be relieved with paracetamol. A less common method to retrieve eggs these days is doing a laparoscopy operation with a general anaesthetic (keyhole surgery through the abdomen).
To enable the timing of egg collection the woman needs to have frequent vaginal ultrasounds and blood tests during the first half of her cycle, 10 to 14 days leading up to ovulation. The aim is to monitor her hormone levels and the development of the maturing follicles producing the eggs.
GIFT and ZIFT
GIFT stands for Gamete Intra-Fallopian Transfer and involves the woman taking medications to stimulate ovulation and then having her mature eggs collected. The eggs are then placed inside the woman's fallopian tubes, along with a quantity of the man's sperm for fertilisation. ZIFT or Zygote Intra-Fallopian Transfer is where the egg is fertilised by the man's sperm in the laboratory, resulting in a zygote (or fertilised egg) and then placed into the woman's fallopian tube.
GIFT and ZIFT are usually used for unexplained infertility and have about a 26% chance of leading to a multiple pregnancy, depending on how many eggs are used.
Even though the success rate for GIFT tends to be slightly higher than for other procedures such as IVF, the trend to perform GIFT procedures has declined rapidly in recent years in favour of newer technologies.
In Vitro Fertilisation or IVF is similar to ZIFT except the retrieved eggs and sperm are placed together for fertilisation in the laboratory and allowed to develop for up to 5 days, until they become embryos. One or two embryos are then selected and placed inside the woman's uterus, called an embryo transfer or ET. The remaining developing embryos are frozen for use at a later date if the fresh embryo transfer is unsuccessful, or for additional IVF pregnancy attempts.
A single or double embryo transfer is a simple procedure (similar to a pap test) where the developing embryo(s) is placed directly inside the woman's uterus, taking about 5 minutes and not requiring anaesthetic.
Some women feel mild discomfort or intermittent cramping during the procedure. IVF is usually recommended for women whose fallopian tubes are blocked or if other fertility treatments have not worked and has a multiple pregnancy rate of about 22%.
ICSI stands for Intra-Cytoplasmic Sperm Injection and was first developed in the early 1990s. It involves the injection of a single sperm directly into a woman's harvested mature egg using a microscope in a laboratory. The fertilised egg is then placed back inside the woman's fallopian tubes or uterus, depending on how long the fertilised egg is left to develop in the laboratory.
This process is used to treat male infertility and is more costly than IVF with a success rate of between 11 and 17% and around a 22% multiple pregnancy rate.
Gamete or Embryo donation
A gamete is an egg or spermatozoa. Gamete donation is when another woman's egg or another man's sperm (or a fertilised embryo from another couple) is used to achieve a pregnancy. If a pregnancy does occur, then the child is not biologically part of one (or both) parents.
Gametes or embryos may be donated anonymously or they may be given by a close relative or family friend. The acceptance of a gamete donation is something that usually takes much consideration for the prospective parents. For more information or support you can go contact the Donor Conception Support Group of Australia.
Sourced with permission from birth.com.au