July 19, 2013 ( – A Swedish study has found that children conceived with a certain type of in vitro fertilization (IVF) have a 51 percent increased risk of intellectual impairment – defined as an IQ score below 70. They also linked the procedure to a small increased risk for autism in cases of twins and triplets.

Scientists studied data from 2.5 million births, and found the heightened risk in cases of babies conceived by a process in which the sperm is injected directly into the mother’s egg, known as Intra-Cytoplasmic Sperm Injection (ICSI). ICSI is used typically to overcome male infertility. 

The scientists behind the study pointed out that while the increased risk was statistically significant, it translates into comparatively small numbers in the real world: 92 per 100,000 (0.092 percent) vs. 62 per 100,000 children (0.062 percent).

“The exact mechanism is unclear, but there are a number of risk factors, from selection of IVF procedures, to multiple embryos, and to pre-term birth,” said study leader Dr. Avi Reichenberg, from the Institute of Psychiatry at King’s College London, according to the Press Association.


“Whilst intellectual disability or autism remain a rare outcome for IVF, being aware of the increased risk associated with specific types of IVF means offspring at risk can be identified and potentially monitored for developmental disorders, ensuring they receive early detection and appropriate support and care,” he said.

An editorial in the Journal of American Medical Association, where the study appeared, also pointed out that IVF in general has been linked to “increases in preterm delivery, low birth weight, neonatal admissions, and perinatal death,” as well as an “increased risk of congenital anomalies.” 

In October 2012, researchers in California released the results of a study that found that children conceived by in vitro fertilization were 1.25 times more likely to suffer from a genetic disorder compared to children conceived naturally.

Another study released last May came to similar conclusions. Researchers found the overall risk of any birth defect when using assisted reproductive technologies was 8.3 percent, compared to the significantly lower 5.8 percent in naturally conceived children.

Interestingly, that study also found a heightened risk of birth defects associated with ICSI as compared to more standard methods of IVF – 9.9 percent for ICSI vs. 7.2 percent for other forms.

According to a 2010 French study – one of the largest on the subject – assisted reproductive technologies double a baby’s risk of deformity. That study found that more than four percent of fertility-treatment children had some form of congenital deformity, compared to the rate in the general population of between two-to-three percent.

In 2011, University of Toronto geneticist Dr. Rosanna Weksberg said that babies born from in vitro fertilization (IVF) are up to 10 times more likely to suffer from rare genetic disorders. Dr. Weksberg called for more research into the subject.

The British government’s Human Fertilisation and Embryology Authority warned in 2009 that IVF babies have a 30 percent higher risk of genetic abnormality.