The expression of the genetic code of our DNA is normally altered several times before conception, and during pregnancy, childbirth and later throughout life. This takes place through the natural switching on and off of genes in response to signals received from the child’s own cells and from the environment. This is called ‘epigenetics’. Although epigentic changes do not act by altering the sequence of the genome directly, if say a tumour suppressor gene is switched OFF, then the rate of mutations in cellular DNA can increase.
Hannah Dahlen, professor of midwifery University of Western Sydney, and founder of the group EPIIC (Epigenetic impact of Childbirth) talks about the research on epigenetic influences during the actual process of normal labour and childbirth in the movie we are screening on 20th Sep called Microbirth.
“In the EPIIC hypothesis, we propose that physiological labour and birth have evolved to exert eustress (a healthy, positive form of stress) on the fetus, and that this process has an epigenomic effect on particular genes, particularly those that program immune responses, genes responsible for weight regulation, and specific tumour-suppressor genes.
Reduced or elevated levels of the hormones cortisol, adrenalin, and oxytocin which are produced during labour may lead to fetal epigenomic remodelling anomalies which exert influence on abnormal gene expression. This reprogramming could manifest in a range of diseases and behavioural problems in the neonate and later on in the adult.” http://theconversation.com/can-caesarean-sections-increase-susceptibility-to-disease-12334
more about epigenetics and health http://www.nature.com/scitable/topicpage/Epigenetic-Influences-and-Disease-895