The list of patients who were potentially involved in the embryo-swapping incident at Assuta Hospital in Rishon Lezion has been narrowed down from 40 to 10, the hospital said in a Friday afternoon update.
A Health Ministry report published on Wednesday revealed that an Israeli woman who became pregnant with the help of fertility treatments was carrying a fetus that was neither genetically related to her nor her husband.
Friday's update further noted that out of the 10, only one patient is considered 'highly likely' to be involved in the incident, but she is not pregnant.
Contact has been made with the patient, Assuta said.
The list was shortened following two days of "intensive testing" in the hospital, during which lab protocol was examined and potential opportunities when the swap may have occurred were mapped.
An Assuta doctor has been assigned to accompany the woman who is carrying the swapped fetus. All actions taken by the hospital are done so with the utmost sensitivity and in adherence to medical confidentiality laws, it said.
"Assuta apologizes for the emotional burden and stress caused to the patients following the discovery," the statement continued. "We are using every resource available to bring tests to an end and to assure our patients."
More about in vitro fertilization (IVF)
Embryo transfer is also known as the final stage in the process of in vitro fertilization (IVF). One full IVF cycle usually takes about three weeks. It requires an individual to suppress their natural menstrual cycle and undergo hormone treatments to stimulate ovum (egg) growth. Then, the ova are extracted and fertilized by professionals in a lab setting. Ideally, this results in several viable embryos, one or two of which will be implanted in the uterus.
The process can be costly, and for some, it is very physically taxing. Many people go through multiple cycles before achieving a viable pregnancy.
When done intentionally, implanting a non-genetically-related embryo into the womb of someone intending to get pregnant is called surrogacy.