13 January 2023

Christine de Die: "The first healthy PGT baby was a true miracle"

She is sometimes asked: How did you do it? Forty years of investing in a centre for clinical genetics at the Maastricht hospital. The only centre in the Netherlands where embryos may be examined for genetic disorders, in order to have a healthy child. "Persevere," is the simple answer. "It wasn't always fun, or easy. Nowadays, work has to be 'your passion,' but sometimes it takes some effort to persevere and later it becomes your passion again. You shouldn't give up too soon, because then it becomes nothing." Prof. Christine de Die on her own development, that of clinical genetics and the first healthy-born babies 25 years ago, who recently returned to her doorstep.

A wonder

She remembers the first days very well. The people who dared to take on this new technology had often been through a lot. "Six miscarriages and two stillborn children, to name one example. They no longer dared to have a spontaneous pregnancy. The preparation process could take up to two years and when these people had a healthy child, it was a celebration! For them as well as for us."

A couple of couples recently contacted her department to ask if she was still working here. They wanted to show her their children, who are now about 20 years old. "Coincidentally, they were all girls. It was a special reunion. 'This doctor made you,' it was said, which of course was not quite true. We were their salvation back then to have a healthy child, though. You see that great gratitude a little less these days. People now take it for granted that all those medical facilities are there, but it was very different back then. It really was a miracle."

Intense discussions

Between 1995 and 2008, the Maastricht hospital helped a number of couples have healthy babies every year. At their own expense, because the government did not want it, yet. Only when embryo selection for certain hereditary conditions was included in the basic insurance package, in 2008, did other hospitals become interested. "Out of customer friendliness, we then started collaborating with Utrecht, Groningen and the AMC, where women could then also go through the IVF process.

Until that time, they had to go to Maastricht for every appointment, which of course is extra burdensome in an already tough process." Which conditions qualify for PGT has always been closely monitored by the national government. There have been intense discussions, especially with political parties that consider human intervention in a pregnancy process undesirable on principle. In 2008, the Balkenende cabinet even nearly fell over it. De Die also always got involved in these discussions in the media. "At the time, there was a lot of demand for PGT to prevent hereditary breast cancer in subsequent generations, but politicians were not keen on it. There was eventually a regulation for it, and thanks to all the media coverage of our center around that debate, applications flew up. "Of course, those parties just didn't want that," she says with a laugh.

She realizes that the debate over PGT can erupt anew with every change of government. Every coalition agreement includes a health care paragraph, with the perennial trio of "abortion, euthanasia and PGT. "The question is always how far you go with these options. PGT is often taken to the extreme in the media, as if we were ever going to select for intelligence or eye color, I think that's really a non-discussion. But where in the early years we mainly selected for serious diseases from which children would die early, soon the demand came from couples with a disease that doesn't manifest itself until later, such as Huntington's or hereditary cancer."

While for diseases from which children die young it is an acceptable option for most couples to terminate the pregnancy after prenatal testing, it is different in such cases, De Die knows. "If you yourself have a very burdensome condition that you would like to spare your child, terminating a pregnancy is actually a denial of your own existence. If your parents had done that, you would never have been there. That's much harder." Meanwhile, 75% of the indications selected for with PGT are such conditions.


Preimplantation Genetic Testing (PGT) - also known as Preimplantation Genetic Diagnostics (PGD) - is the medical term for embryo selection. Couples with a greatly increased risk of having a child with a serious inherited disorder or who have a high risk of miscarriage due to a chromosomal abnormality are eligible for it.

Through IVF treatment (that is, in a test tube) fertilisation takes place. One or more cells are then taken from each embryo. These biopsies are examined in the laboratory of the PGT center Maastricht UMC+ for the hereditary disorder for which the treatment has been requested. Only the embryo without the hereditary predisposition for this disease is placed in the uterus. The chance of a successful pregnancy is currently about 30%.

Looking back and forward

Looking back, she has great satisfaction with all that has been built in Maastricht. Looking ahead, she worries about the costs of current health care ("unsustainable, but how do you turn that around?") and the defensive atmosphere ("everything must be excluded, while the patient does not necessarily benefit from even more diagnostics, they just want a solution").

To young staff, especially women, she tries to pass along the message that they should guard their limits. "Many young women with families are in a split. I myself have three children, had yet to get my doctorate while I was a specialist, but my husband was a sociologist and at home a lot, so that made a difference. I try to encourage employees to stop for a moment now and then, especially when something is complicated. Think for a moment," I often say. By guarding your limits, you keep fun in your work, because we have a wonderful profession, but if you are overloaded, nothing is wonderful anymore."

She herself has never had a plan for her career, and so there is no plan for her retirement. She enjoys working in the garden and cycling with her husband. "I think: we'll see how it goes. You just have to adapt a little bit to the situation. Something new always comes your way."

This news item is previously published by Maastricht UMC+.