In assisted reproduction , could you get to know the sex of the child? Or is it possible to make a choice of sex? Here we answer the most frequently asked questions about this subject in assisted reproduction treatments.
What does the sex of the child depend on?
DNA is the genetic material of the cell found in chromosomes. The cells of the human body contain 46 chromosomes arranged in 23 pairs of which one pair, known as sex chromosomes, determines the sex of the individual. Eggs and sperm have only half as many chromosomes. When the egg and the sperm unite in fertilisation, all 23 pairs are obtained. The ovum always has the X chromosome, and the spermatozoon determines the sex, depending on whether it has a Y or an X chromosome.
Is it technically possible to select the sex of the child in assisted reproduction?
Once the embryos reach the blastocyst stage, in some cases a biopsy of the embryo is taken and the trophectoderm (the outer layer that surrounds them) is analysed using pre-implantation genetic diagnosis (PGD). There is a specific test, known as PGT-A or pre-implantation genetic testing for aneuploidy, which is often used in assisted reproduction to detect abnormalities in chromosome number, which will help select chromosomally normal embryos. However, this test also allows the sex of the child to be known and selected, although it is not considered when selecting healthy embryos.
Will I be able to choose the sex of the baby?
Currently in Spain, Law 14/2006 on Assisted Human Reproduction does not allow the selection of the sex of the child or the genetic manipulation of embryos for non-therapeutic or unauthorised purposes. There are cases in which the therapeutic purpose of sex selection can be demonstrated, for example when there is a serious hereditary sex-linked disease, and its transmission is to be avoided. However, nowadays, the genetic diagnosis of the disease itself can be performed without the need for simple sex selection. Sex selection for X-linked diseases used to exclude healthy embryos, which we can now diagnose thanks to a special type of genetic diagnosis of diseases, PGT-M.
How is the choice of the sex of the child requested?
In Spain there is the National Commission for Assisted Human Reproduction, a collegiate body of the Ministry of Health. This commission oversees advising on assisted reproduction techniques and assessing and authorising each specific case. If there is the alternative of detecting the disease in the embryos, sex selection will not be authorised.
Some theories on natural sexual selection of infants
In assisted reproduction, PGD is available in cases where the sex of the child is to be selected. However, there are several theories on natural sex selection methods, but they are not scientifically proven. Some of them are the Shettles method and the Whelan method, which suggest that in order to have a child of a certain sex, it is necessary to have sexual intercourse at specific times during the menstrual cycle.
