A Dutch medical center has launched an investigation after uncovering that dozens of women may have been fertilized by the wrong sperm. Half of the women who underwent IVF treatment are pregnant or had their babies.
The University Medical Center in Utrecht (UMC) said on Tuesday that a "procedural error" may have caused up to 26 women to be fertilized with the wrong sperm cells at its IVF treatment laboratory.
The "error" took place over several months between mid-April 2015 and mid-November 2016 during in vitro fertilization, UMC said in a statement.
"During fertilization, sperm cells from one treatment couple may have ended up with the egg cells of 26 other couples," the center said.
They added that "there's a chance that the egg cells have been fertilized by sperm other than that of the intended father."
The error was discovered when a new procedure was introduced in the fertility clinic, UMC said on a "frequently asked questions" page on the incident.
Although some of the couples still have frozen embryos available, those egg cells may have also been already fertilized with the wrong sperm, UMC said.
Half of the women who underwent IVF treatment are pregnant or have already given birth to their babies. The couples have already been informed, the center said.
"The UMC's board regrets that the couples involved had to receive this news and will do everything within its powers to give clarity on the issue as soon as possible," the statement said.
During in vitro fertilization, mature eggs are retrieved from a woman's ovaries and fertilized by a partner or donor's sperm cells in a laboratory. The embryos are then implanted back in the woman's uterus.