by Gillian Parker, Tamalpais HS
It is still unclear when human babies/fetuses begin to feel pain. The first step to feeling pain is to develop the necessary neuroanatomy. Evidence suggests that the necessary anatomical developments are in place at as early as 26 weeks gestation. When a fetus of approximately 26 weeks is exposed to noxious stimuli, it will respond to them, although minimally (Derbyshire, 2006). There are studies which claim to record evidence of fetal expressions of pain and/or distress. In one particular study, 8 female and 7 male fetuses were scanned with a 4-D ultrasound four times during the second and third trimesters of pregnancy, or 24 to 36 weeks gestation. The study specifically focused on expressions of pain or distress. Researchers concluded that as the fetus matured, so too did its visible responses to stimuli. However, the fetuses were not provoked in any way, and these responses did not reflect the fetuses' emotional or cognitive state (Reissland, 2013).
Although fetuses technically have the anatomy to experience pain around 26 weeks gestation, it is unclear whether or not they actually experience pain as we know it, because of their minimal level of consciousness. Pain is defined as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage” by the International Association for the Study of Pain. In spite of its anatomy, it is thought that fetuses do not experience true pain, because they are not conscious of it, and have no experience or memory to base their pain on. The fetus is actually provided natural sedatives from the placenta just as it receives nutrients from it. The fetus is asleep for the duration of gestation. It is suspended in a warm, cushioned environment and it does not know anything but this. It is unlikely that it would be able to experience true pain, as it is unconscious and has no basis for comparison. Essentially, the fetus has not yet learned how to experience pain, or identify itself as an individual (Koch, 2009).
In conclusion, it is unclear exactly when the fetus reaches a conscious perception of pain. Though the fetus develops the anatomy to respond to pain during the latter part of pregnancy, and can even make facial expressions of pain and/or distress, there is no correlation with the fetus’s actual comfort level. The placental sedation of the fetus means that it has no memory or “experiences” and therefore is unable to experience pain in the conscious way that adults and children understand. Further research may someday uncover more information on this complex and controversial question.
In conclusion, it is unclear exactly when the fetus reaches a conscious perception of pain. Though the fetus develops the anatomy to respond to pain during the latter part of pregnancy, and can even make facial expressions of pain and/or distress, there is no correlation with the fetus’s actual comfort level. The placental sedation of the fetus means that it has no memory or “experiences” and therefore is unable to experience pain in the conscious way that adults and children understand. Further research may someday uncover more information on this complex and controversial question.
3-D/4-D Ultrasound of Fetus from Fetal Expression Photo Gallery
See more 4-D Ultrasounds at http://www.fetalexpressions.ca/gallery.php
Pain/Distress Fetal Expression from Facial Expression Study
Read the study of fetal expression of pain and distress at http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0065530.
For more information on birthing babies, attend the Marin Science Seminar on Wednesday, March 26 at Terra Linda High School with Sheri Matteo, RN, CNM of Prima Medical Foundation, Marin General Hospital. Find out more at http://www.marinscienceseminar.com/print/midwifery2014.pdf.
Sources:
Christof Koch. (2009, August 1). When Does Consciousness Arise in Human Babies?. Retrieved March 16 from http://www.scientificamerican.com/article/when-does-consciousness-arise/?page=1
Hugo Lagercrantz and Jean-Pierre Changeux.(2009). The Emergence of Human Consciousness: From Fetal to Neonatal Life. Retrieved March 16, 2014 from http://www.nature.com/pr/journal/v65/n3/full/pr200950a.html#bib16
Nadja Reissland, Brian Francis, James Mason. (2013, June 5). Can Healthy Fetuses Show Facial Expressions of “Pain” or “Distress”?. Retrieved March 16, 2014 from http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0065530
Stuart W G Derbyshire. (2006, April 15). Can Fetuses Feel Pain?. Retrieved March 16, 2014 from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1440624/
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