Embryo implantation failure is determined as the situation in which pregnancy is not achieved after the transfer, on at least 3 occasions, of good quality embryos in an in vitro fertilisation (IVF) cycle.
In order for pregnancy to be achieved after an IVF treatment, it is necessary that the embryo implants in the mother's uterus.
The clearest indicators of implantation failure are the absence of pregnancy and the start of menstruation about two weeks after the embryo transfer.
In a natural cycle, the sperm fertilises the egg in the Fallopian tubes. As the new embryo develops, it travels to the uterus. In other words, for embryo implantation to occur, there must be a proper understanding between the embryo and the uterus.
The embryo transfer in an IVF cycle must take place at the ideal moment within the implantation window. This window refers to the period of time in which the endometrium is in optimal conditions to receive the embryo. This period of time is usually between days 20-24 of the menstrual cycle in most women. It usually lasts 4 days.
The main factors that influence the success of embryo implantation in assisted reproduction are endometrial receptivity, embryo quality and the efficiency of the transfer technique. If the transfer is performed in a normal endometrium with a quality embryo, the embryo has a high probability of successful implantation.
Although embryo implantation failures do not usually present specific symptoms in in vitro fertilisation, some indicators may suggest a possible implantation failure, although these are not definitive and may have other reasons. Some of these possible symptoms are:
At IVF-Life we carry out certain tests that allow us to analyse the causes of implantation failure and thus help fertility specialists to make an accurate diagnosis.
The endometrial receptivity test is a personalised test that evaluates the expression of 48 genes involved in the development of endometrial receptivity and determines the state of receptivity of the endometrium during the window of implantation.
It helps us to identify the best time of the endometrium for embryo transfer, which increases the probability of implantation and, therefore, pregnancy.
With this test we can detect displacements of the window of implantation, present in 20-25% of women with implantation failure.
The immunological study is a test used to map and evaluate the immune status of the patient. This test provides a detailed profile of different cells and molecules of the immune system. It helps to identify immune imbalances and dysfunctions that may contribute to various diseases.
If the immunological tests reveal an abnormal level of immune cells, tailored immunotherapy is recommended for each patient to improve reproductive outcomes. Pregnancy rates after endometrial receptivity testing have been shown to increase by 40%.
Preimplantation genetic testing is the general name given to the tests performed on the embryo before it is transferred to the mother's uterus. The purpose of this test is to detect possible serious genetic or chromosomal diseases in the embryo.
With this technique we are able to ensure that babies are born free of these genetic diseases.
This test is performed in cases where uterine pathology is suspected or where there are difficulties in achieving pregnancy through fertility treatment. This technique allows direct visualisation of the endometrial cavity to study its morphology and function.