June is World Fertility Month and from the CREA Center of Valencia, they explain in the following article the embryo transfer. This is the last step in the in vitro fertilization (IVF) process and, therefore, one of the most important in the Assisted Reproduction process. It consists of depositing the embryos precisely and carefully inside the uterus, facilitating their implantation and the success of the pregnancy.
How and when is the embryo transfer performed?
The final success of IVF depends on the embryo transfer and the implantation of the embryo in the uterus. The transfer is a simple and painless procedure that does not require anesthesia.
The embryo transfer is performed in an operating room in order to work in the most appropriate sterile conditions. Between two and six days must elapse between fertilization and transfer (except in the case of frozen embryo transfer) and, previously, the woman will have been prescribed a treatment with progesterone in order to strengthen and prepare the endometrium for the implantation of the embryo.
Regarding the embryo transfer process, first an ultrasound is performed to assess the position of the uterus and the state of the endometrium. Generally, it is recommended that the patient come with a full bladder, since this rectifies the position of the uterus, facilitating the entry of a fine cannula.
The embryo transfer must be delicate, avoiding touching the fundus of the uterus, as this could provoke intrauterine contractions that would hinder embryo implantation.
Finally, the cannulae are carefully removed and it is verified that the embryo containing the thinnest cannula has been deposited in the uterus.
Care after embryo transfer
After the embryo transfer, the embryo remains attached to the uterine walls by a tiny drop of culture and, if it does not implant, it is reabsorbed and disappears (it can never be detached). Even so, after the embryo transfer, it is recommended to avoid efforts that could produce uterine contractions and to keep relative rest for two weeks. During this time it is also essential to maintain the administration of progesterone so that the embryo can implant correctly. After two weeks, a pregnancy test is performed.
Other care that should be taken into account after the embryo transfer are:
- Lead a quiet and relaxed life avoiding intense physical exercise. The patient can drive, walk and go to work, as long as the function she performs does not involve effort or intense and prolonged physical activity. It is advisable to be psychologically calm.
- Avoid immersion baths such as bathtub, swimming pool or beach to be away from possible infections.
- Do not have sexual intercourse until the pregnancy test to avoid contractions produced, for example, by orgasms.
- Eat a healthy diet, reducing the consumption of coffee and alcohol and increasing the consumption of foods rich in fiber to avoid constipation (whole grain bread, cereals, fruits with fiber, legumes and vegetables).
- Drink liquids, making sure that urination is adequate and that there is no notable fluid retention, since in the days following the embryo transfer, the woman may feel a little bloated.
From the time of the transfer until the pregnancy test, many women do not notice anything at all, although others experience minor discomfort similar to that of menstruation, due to the size of the ovaries, which has increased considerably during the stimulation.
It is also possible that a small amount of bleeding may occur due to embryo implantation, small endometrial desquamations or even progesterone treatment. If the bleeding persists, it is recommended to rest until 24 to 48 hours without spotting and to maintain the medication, since it is not possible to find out how the embryo evolves until the pregnancy test. If the bleeding is abundant and does not stop, a doctor should be consulted.
What happens with the embryos that are not transferred?
However, at CREA we are committed to the transfer of a single embryo to avoid the problems associated with multiple pregnancies, both for the mother-to-be and the babies.