Infants conceived with techniques used in fertility clinics, are four times more likely to have certain birth defects and malformations than children conceived naturally, according to a study by researchers at the University of Lund ( Sweden). By in vitro babies, the risk of childhood cancer is great. Specifically, they have a 42 % chance of having a childhood cancer. Experts say that the figures are evident but they have not yet determined how the disease develops. Among the defects that have been detected are heart problems, cleft lip, cleft palate and abnormalities in the esophagus or rectum, which normally occur once every 700 births. Assisted reproductive techniques, such as fertilization " in vitro ", which requires doctors to work with embryos and sperm outside the human body, increased these serious dangers. "I think it's important to consider the fact that there may be a risk of birth defects", says Jennita Reefhuis , epidemiologist from the Centers for Birth Defects Research and author of a study published in the online journal "Human Reproduction". Reefhuis also said that although her study linked fertility procedures to birth defects, it did not demonstrate nor explained this connection. If the connection is real, it is not known whether the procedures increase the risk of these malformations, or whether infertility itself raises this risk. On the other hand, Dr. James A. Grifo, director of the fertility clinic at the Medical Center of New York University, said that more research is needed to test these findings, because the study was done with only 281 women who had undergone fertility treatment. Nevertheless, "the results are worrisome but, with a small sample of patients, we need to do a larger study", added Dr. Grifo. Also, Dr. Alan R. Fleishman, vice president of March of Dimes, said: “I think it's an important study that confirms the direction in which we were concerned, that of an increase in some structural birth defects in children born with assisted reproductive techniques. Women who choose to undergo this fertility treatment should be informed of the risk of birth defects in their children”. Fertilization "in vitro" could be defined as the taking of male and female gametes and the realization of their union outside the human body to transfer the fertilized embryo into the uterus of the mother to implantation and subsequently birth. In addition to the risk of malformations in the child already indicated, fertilization "in vitro" goes “against nature” And nature never forgives, it is relentless. Clemente Ferrer Independent Forum of Opinion (Spain)