by Dr Agilan Arjunan, Fertility Specialist & Gynaecologist, KL Fertility Centre (Malaysia)
Conceiving a child and procreating is a natural human tendency. Many of usare blessed with children . However, some couples do face obstacles in their journey towards parenthood.
Modern fertility treatment such as an in-vitro fertilisation ( IVF) has helped many couples to conceive. Current IVF technology had seen many advancements , thus achieving a higher pregnancy rate . IVF has also become safer for patients.
Common risks associated with an IVF procedure are ovarian hyperstimulation ( OHSS) and multiple pregnancy.
The risk of OHSS has reduced dramatically with the current IVF protocols. However, the risk of multiple pregnancy varies depending on several factors such as the age of the woman, quality of the embryo and number of embryo transferred into the womb.
A well established IVF centre have their own medical guidelines pertaining to number of embryos to be transferred into the womb. Some countries have their own national guidelines which advises fertility specialists on number of embryos to be transferred based on patient and embryo factors.
Statistical probability points towards a higher pregnancy rate with increasing number of embryos transferred . In conclusion, the more embryos transferred into the womb, the higher the pregnancy rate.
So, why are IVF doctors concerned about the number of embryos transferred ?
Artificial Reproductive Technology ( ART ) or specifically In-Vitro Fertilization (IVF) , gave the world our first IVF baby in 1978. The birth of Louise Brown gave infertile couples a new hope towards parenthood .
Over the last 3 decades , IVF technology has evolved and advanced.
Ovarian stimulation has become safer and more patient-friendly . Fertility laboratory techniques has improved tremendously.
The most important breakthrough development in the fertility laboratory technique is the ability to freeze and thaw embryos successfully.
The original method of freezing and thawing the embryos is associated with higher embryo loss.
The current technique of embryo freezing known as vitrification has improved the embryo survival rate. In an established IVF laboratory, the survival rate of thawed embryos with vitrification technique is close to one hundred percent .
In 1984, the first baby via frozen embryo transfer (FET) was born. Since then , many fertility clinics has adopted frozen embryo transfer as part of their strategy in their IVF protocol.
Embryo transfer procedure can be divided into fresh and frozen embryo transfer based on the timing of the embryo transfer.