The first ever child born from IVF was Louise Brown. She only recently turned forty, which means that we are still a long way away from fully understanding whether there are any serious health-related issues connected to this method of conception.
In a small study which was conducted on 52 U.S. teens that were conceived by IVF, eight of them were diagnosed with hypertension. On the other hand, only one out of 43 teens that were conceived naturally had issues with high blood pressure. High blood pressure then raises the risk of stroke and heart attacks among other health issues.
The study also showed that 3.5 percent of adolescents have hypertension. If we focus solely on teens conceived from assisted conceptions, that number rises to 15 percent. Although these are not terribly high numbers, they should still prompt us to perform more routine checkups.
From 2014 until today, some eight million babies were conceived in assisted pregnancies, according to a report released by the International Committee Monitoring Assisted Reproductive Technologies in Palo Alto.
During a study performed in 2012, Swiss scientists discovered that children from assisted conceptions have blood cells that resemble ones found in much older adults. Those vessels displayed stiffness and thicker walls only found in people much older than them. These vessels could potentially contribute to cardiovascular disease in the future.
There is a chance that these abnormalities in the blood cells are related to the chemical tags, better known as epigenetic marks. These tags are implemented into histones and they can ramp gene activity either up or down. Outside factors like chemicals, diet, or stress can all have an effect on those marks and in doing so alter gene regulation.
During in vitro fertilization, mature eggs are fertilized with sperm in a laboratory and then implanted into a woman’s uterus. During a study conducted on mice, it has been found that in vitro fertilization alters an epigenetic mark changing the regulation of a gene in the aorta, the main artery that can be found in the body. This automatically raised the number of mice that developed hypertension.
What Does This Mean for Humans?
During IVF in humans, the critical period starts when the eggs are harvested and ends when the embryo is placed into the uterus. During this period there is the biggest chance for epigenetic change to occur.
More tests must be performed in order to discover which epigenetic mark is responsible for the cardiovascular system. In determining this scientist may be able to pinpoint which outside factors should be avoided.
Until such information is collected researchers must continue to monitor people conceived in this way. It should become common practice to ask patients for fetal and neonatal history. It is important for future generations that we continue monitoring this situation to find out if there are any other potential issues.