The A-Z of fertility treatment
The topic of fertility treatment is very complex and extensive. Especially when you are dealing with it for the first time, you quickly feel overwhelmed by all the technical terms.
Our fertility lexicon from A-Z covers all the important topics and terms that you will come across again and again on your fertility journey. We have also created a section with the most frequently asked questions of our patients. However, we are always happy to provide you with help and advice and answer any questions you may have in a personal first consultation.
- Killer cells
see "KIR genes"
- KIR genes
Summary
KIR is an abbreviation for "killer cell immunoglobulin-like receptors", which are substances on the outside of killer cells that play an important role in our immune system. Each person differs in the KI receptors, as there are 16 different KIR genes on which the building instructions for the KI receptors are stored. Pregnancy is a particular challenge for the immune system. Here, a lack of certain KIR genes can lead to problems. In this case, the embryo either cannot implant at all or the early pregnancy is lost (again and again). An examination makes sense here. If the results are unfavourable, treatment with a drug is given and only one embryo is transferred at a time. The examination and drug treatment of the KIR genes is associated with additional costs.
Detailed explanation of the KIR genes ("killer cells")
KIR is an abbreviation for "killer cell immunoglobulin-like receptors". Receptors are substances on the outside of a cell that pick up a certain signal and pass on a message to the inside of the cell. Therefore, think of a cell as a building with numerous television satellites - antennas attached, each aimed at a different programme. When a particular programme is broadcast by a satellite, it is picked up by a particular antenna and relayed to the television inside the building.
The AI receptors are located on the natural killer cells that play an important role in our immune system. Each person differs in the AI receptors, as there are 16 different KIR genes on which the building instructions of the AI receptors are stored. The killer cells have the important task of distinguishing between friend (the body's own cells) and foe (for example tumour cells), and the AI receptors play an important role in this. This requires a balanced ratio of the different KIR genes.
Pregnancy is a particular challenge for the immune system, since half of the child's genes come from a "foreign" person, the child's father. Here, a lack of certain KIR genes or their receptors can lead to problems. In this case, the embryo either cannot implant or the early pregnancy is lost (again and again).
The examination of the KIR genes is therefore useful if the treatment is not successful or if there is repeated loss of early pregnancy. The examination is carried out in the laboratory by taking blood samples. Depending on the presence or absence of certain KIR genes, the results can be divided into three groups: AA, AB and BB. If the group AA is present, infertility is partly caused by this finding. Fortunately, there are two ways to solve this problem:
1) The use of medication containing the so-called growth factor G-CSF (granulocyte colony stimulating factor). Originally developed for cancer therapy, this product helps to stimulate the formation of white blood cells (leukocytes).
2) In addition, in vitro fertilisation treatment only transfers an embryo if certain KIR genes are missing. This procedure reduces the risk of miscarriage.
The examination of the KIR genes is associated with additional costs, and in some cases the drug therapy is not covered by the health insurance. We try to keep your costs for the analysis as well as for the possibly necessary therapy as low as possible.
- Kremer Test
The Kremer test checks whether sperm cells can enter the cervical mucus and survive there. Antibodies can be present in the cervical mucus which are directed against the sperm cells and make them immotile. This can be an obstacle for the sperm cells on their way to the egg cell.
To find out whether there are antibodies against sperm cells in the cervical mucus, a sample of the cervical mucus is taken from the cervix with a pipette. At the same time, a sperm sample from the partner is needed; this sample can either be obtained directly at the Kinderwunschzentrum an der Wien or alternatively brought from home within 60 minutes, warm from the body. In the laboratory it is then checked whether the sperm cells are able to migrate unhindered into the mucus and move around there. If sperm cells become immotile in the cervical mucus, it can be concluded that antibodies are present.
An abnormal test result can - if there are no other reasons - be a cause for the absence of a pregnancy.