The number of eggs transferred during ET is considered the most important decision in the entire procedure. But, did you know that transferring more embryos in IVF doesn’t always increase the chances of success?
Then, will single embryo transfer work well? This article will give you a detailed view of how many embryos are transferred in in vitro fertilization to witness optimal success.
Significance of embryo transfer in IVF
Before discussing the topic of whether a patient needs to undergo single or multiple embryo transfers, everyone should understand the significance of embryo transfer and the success rate of embryo transfer.
ET is the most essential part of the in vitro fertilization procedure, and it is also the last step. A successful embryo transfer promotes your body to the next stage, implantation and pregnancy.
Yes, if an embryo transfer is successful and implantation takes place, women undergoing IVF may start sensing early pregnancy symptoms. So, embryo transfer is indeed crucial in the overall in vitro fertilization treatment.
But how many fertilized eggs should be transferred for optimal results? Take a look at it.
Number of embryos transferred through IVF
Number of embryos transferred through IVF
The number of embryos transferred through the in vitro fertilization treatment can vary according to the major factor, age. Fertility experts consider transferring the fertilized eggs as per the age of the women undergoing this treatment.
ASRM, The American Society of Reproductive Medicine recommends several embryo transfers based on a woman’s age. The society suggests a single embryo transfer for women under 38 years and not more than 3 fertilized eggs for females from 38 to 40 years.
On the other side, the number of eggs varies as per the stage of eggs while transferring. Generally, fertility experts recommend two different types of embryo transfers such as single and multiple transfers.
Single Embryo Transfer (SET)
This is a method of transferring only one embryo during in vitro fertilization. Many popular associations including the CDC, American Society for Reproductive Medicine, and Society for Assisted Reproductive Technology recommend one embryo transfer for IVF patients.
Why is it so? These associations recommend this because SET is the safest and gives optimal pregnancy outcomes if the embryo is free from chromosomal abnormalities.
Who can consider Single Embryo Transfer?
Some conditions state that the patient is eligible for single embryo transfer, including:
- Women younger than 38 years old.
- Women with optimal or high quality of eggs and embryos.
- Patients who haven’t undergone treatment such as IVF.
Multiple or Double Embryo Transfers (DET)
Multiple or double embryo transfers take place in IVF, believing that this can increase the chances of pregnancy outcomes. In addition, DET is more likely to result in multiple pregnancies that are twins or even quadruples.
Reports suggest that transferring two top-quality blastocysts results in multiple gestation rates between 50% and 60% and triplet gestation from 2 to 5%.
Who can consider multiple embryo transfer?
Generally, women older than 35 can consider Double Embryo Transfer. If a patient experiences no success even after undergoing multiple IVF cycles can prefer double embryo transfer.
Ultimately, prioritise your doctor’s advice and choose the number of embryo transfer that helps to witness optimal pregnancy results.
Types of Embryo Transfer
So, hope you understand what single and double embryo transfers are and who can choose them. But there are some stages of the embryo also available, transferring the fertilized eggs during different development stages can provide you various results.
Fresh embryo transfer
Fresh ET is nothing but transferring the fertilized eggs after a certain number of days, which is almost 5 to 6 days of egg retrieval. Through this type of transfer, many doctors suggest one embryo transfer. Because transferring double embryos may increase the chances of multiple pregnancies and other complications.
Frozen embryo transfer
This is a procedure of freezing the retrieved eggs during the IVF and saving them for the future. Frozen ET will happen approximately 4 weeks post the egg retrieval. So, patients undergoing IVF treatment can take sufficient time for recovery, and then undergo embryo transfer. However, SET is recommended during the frozen embryo transfer.
Cleavage embryo transfer
A cleavage embryo is a development stage of the egg after fertilization. It is generally 2 or 3 days after fertilizing the eggs. During this stage, the cells in the embryo start dividing and fertility specialists recommend when and how many embryos to be transferred into the uterus.
Blastocyst embryo transfer
Blastocyst is the stage when fertilized eggs start developing into a single-layered sphere of cells with cells grouped. Embryos reach the blastocyst stage and have 60 to 120 cells that improve the chances of a successful pregnancy compared to the cleavage stage.
Final verdict
Nowadays, fertility experts follow multiple embryo transfers to increase the chance of optimal pregnancy results through IVF. Because every couple undergoing an IVF procedure expects successful outcomes.
In this case, choosing the best fertility expert becomes very important as the doctor’s expertise and experience decide whether you need single embryo transfer or multiple embryo transfer. Adding to this, every individual’s body is different and reacts differently to the treatment as per their reproductive health.
Therefore, keep such things in mind and seek emotional support during IVF for good pregnancy outcomes.
People also ask
Single embryo transfer failure happens because of issues with the uterus including fibroids, a thin endometrial lining, and polyps. Plus, undetected genetic or chromosomal abnormalities can also be a reason for SET failure.
A significant reason for transferring two embryos is increasing the chances of optimal pregnancy outcomes. But, there is a chance for failure of IVF treatments too, because of reasons like abnormal embryos or sperm and the uterus is not receptive. If any one of the embryos is poor quality, there is a chance for failure of the entire embryo transfer.
When it comes to the safest and optimal option, transferring a single embryo during the IVF cycle is good. And, women over the age of 35 have better chances of successful conception with double embryo transfer. Factors like age, reproductive health, and quality of sperm and embryo play a pivotal role, so consider your fertility expert’s advice throughout the IVF journey.
No, the chances of getting pregnant after embryo transfer are not sure and it differ according to every individual. Your reproductive health and overall response to fertility medications along with embryo quality decide the optimal pregnancy outcomes.
