--- description: A Dutch lab may have inadvertently fertilized 26 women’s eggs with the wrong sperm. Half the women are already pregnant or have given birth. title: Clinic May Have Fertilized Eggs of 26 Women With Wrong Sperm image: https://static.time.com/v3/assets/bltea6093859af6183b/blt563dae2f629bb662/6988b415656a3f8ff8bce41b/gettyimages-150775078.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 ---  * [World](/section/world/) ## World Update your preferences in [Account Settings](/account/preferences/) Close * [The Netherlands](/tag/the-netherlands/) ## The Netherlands Update your preferences in [Account Settings](/account/preferences/) Close # A Dutch Clinic May Have Fertilized the Eggs of 26 Women With the Wrong Sperm by [Feliz Solomon](/author/feliz-solomon/) ## Feliz Solomon Update your preferences in [Account Settings](/account/preferences/) Close Dec 28, 2016 9:00 AM CUT  Artificial fertilization after intracytoplasmic sperm injection, seen at the University Women's Hospital Bonn in Bonn, Germany on March 15. Artificial fertilization after intracytoplasmic sperm injection, seen at the University Women's Hospital Bonn in Bonn, Germany on March 15.Ulrich Baumgarten—Getty Images by [Feliz Solomon](/author/feliz-solomon/) ## Feliz Solomon Update your preferences in [Account Settings](/account/preferences/) Close Dec 28, 2016 9:00 AM CUT A medical lab in the Netherlands may have inadvertently [fertilized 26 women’s eggs](http://www.bbc.com/news/world-europe-38445201 "undefined") with the wrong sperm, in a bizarre mix-up revealed after half of the women had already either become pregnant or given birth. The BBC reports that the University Medical Center in Utrecht admitted to a “procedural error” during in-vitro fertilizations between April 2015 and November 2016, and that an investigation has been launched. “During fertilization, sperm cells from one treatment couple may have ended up with the egg cells of 26 other couples,” the center said in a statement cited by the BBC. “Therefore there’s a chance that the egg cells have been fertilized by sperm other than that of the intended father,” it continued, adding that there was only a small chance that the wrong sperm actually did come into contact with the eggs in question. While half of the couples have already had children or are currently carrying them, the other half have frozen embryos still in the lab. Those embryos could have been misfertilized, the center’s statement said. According to the BBC, all of the affected couples have been informed of the potential error, and the medical center “regrets that the couples involved had to receive this news.” IVF, as in-vitro fertilization is commonly called, is a form of assisted reproductive technology by which eggs are removed from a woman’s ovaries and fertilized in a lab. The fertilized embryos can then be frozen until ready to be implanted in the uterus. The procedure is typically sought by women or couples who have fertility or genetic problems affecting pregnancy. Similar errors have occurred in the past, with the wrong sperm fertilizing the egg of an ethnic Chinese woman in Singapore who gave birth in 2010, according to the BBC. She reportedly sued her fertility clinic for negligence after she noticed that her son’s skin and hair color were markedly different than that of her Caucasian husband. \[[_BBC_](http://www.bbc.com/news/world-europe-38445201 "undefined")\] ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/4618730/netherlands-clinic-in-vitro-fertilization-wrong-sperm/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/4618730/netherlands-clinic-in-vitro-fertilization-wrong-sperm/"},"headline":"A Dutch Clinic May Have Fertilized the Eggs of 26 Women With the Wrong Sperm","datePublished":"2016-12-28T09:00:28.000Z","dateModified":"2026-02-23T02:29:01.787Z","description":"The University Medical Center in Utrecht has admitted to a 'procedural error'","url":"https://time.com/4618730/netherlands-clinic-in-vitro-fertilization-wrong-sperm/","keywords":["The Netherlands","fertility","IVF","onetime"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/blt563dae2f629bb662/6988b415656a3f8ff8bce41b/gettyimages-150775078.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Feliz Solomon","jobTitle":null,"url":"https://time.com/author/feliz-solomon/"}],"articleSection":"World","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/blt563dae2f629bb662/6988b415656a3f8ff8bce41b/gettyimages-150775078.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"GERMANY, BONN, University Women's Hospital Bonn, Department of Endocrinology and Reproductive Medicine, Our picture shows artificial fertilization after ICSI (intracytoplasmic sperm injection).","caption":"GERMANY, BONN, University Women's Hospital Bonn, Department of Endocrinology and Reproductive Medicine, Our picture shows artificial fertilization after ICSI (intracytoplasmic sperm injection).","creditText":"Ulrich Baumgarten—Getty Images","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/world/","name":"World"}},{"@type":"ListItem","position":2,"item":{"@id":"/tag/the-netherlands/","name":"The Netherlands"}},{"@type":"ListItem","position":3,"item":{"@id":"https://time.com/4618730/netherlands-clinic-in-vitro-fertilization-wrong-sperm/","name":"A Dutch Clinic May Have Fertilized the Eggs of 26 Women With the Wrong Sperm"}}]}] ```