The date was confirmed by the Swiss government on Wednesday after the Swiss public approved the move in a referendum in June 2016, becoming the last country in Europe to do so.
The law on medically assisted reproduction will be changed to allow pre-implantation genetic diagnosis – the testing of embryos during in-vitro fertilization (IVF) before they are implanted in the womb.
The aim is to detect genetic anomalies and serious hereditary conditions, such as cystic fibrosis, in order to prevent affected embryos being selected for implantation.
In-vitro screening of embryos for fetal aneuploidy, such as Down's Syndrome, will also be allowed.
The tests will increase the chances of a successful pregnancy and allow couples who know they carry a genetic disorder to avoid passing it on to their children.
Selection based on gender or other characteristics is explicitly forbidden, unless the risk of passing on a serious condition cannot be avoided in any other way.
In order to facilitate the testing the number of embryos that can be created during IVF will be increased from three to 12, with freezing allowed. Previously the law only allowed three embryos to be created which must all be implanted immediately.
According to the government every year around 500-1,000 couples out of a total 6,000 who go through IVF treatment will opt for the testing.
The test will not be covered by compulsory medical insurance.
Until now genetic screening has only been allowed on pregnant women at around 9-12 weeks of pregnancy, whether the baby was conceived by IVF or naturally.