If I Only Had A Heart…
November 16, 2021
by David Prentice, PhD
In the classic tale The Wonderful Wizard of Oz by L. Frank Baum, perhaps most recognized by the 1939 movie version starring Judy Garland, young Dorothy Gale from Kansas and her dog Toto are transported via tornado to the strange Land of Oz and undertake a journey to see the Wizard of Oz in hopes he can return them to their Kansas home. Along her path on the Yellow Brick Road, Dorothy acquires three traveling companions who also have requests they hope the Wizard will grant, to give them each something they seem to lack: a brain, a heart and courage. The group’s progress and attempts to win the favor of the Wizard are hindered and harassed repeatedly by the Wicked Witch of the West and her minions, including incessant taunts about their shortcomings as well as a dire warning for Dorothy: “I’ll get you, my pretty—and your little dog, too!”
Near the end of the story, the Wizard bestows on members of the group a gift. However, the gift was not the characteristic they originally sought, but rather a recognition that they already possessed those attributes which they were told they lacked. And for Dorothy, the realization she had a home that she valued.
There is in some sense a certain parallel with the journey of a human being during embryological development, including harassment and science denial by various naysayers, especially in the context of current court cases related to abortion.
Some abortion providers have contended that the human embryo at six weeks gestation has no heart, no blood circulating and no accompanying heartbeat, and that what is detected by ultrasound at that age is electrical activity from cells that will become the heart. Some have also questioned whether the doctors who made such statements slept through medical embryology. Certainly, it’s a poor worker who understands neither the subject of their work nor the function of their tools.
The heart is the embryo’s first functioning organ, with the first heartbeats occurring approximately day 22-23 after fertilization (the sixth week of gestation in pregnancy), followed by active fetal blood circulation by the end of the sixth week. The heart forms very early in embryogenesis because the embryo’s survival requires circulation of oxygen-carrying blood, a fact that is validated by all embryology textbooks. Passive oxygen diffusion at that age is insufficient to support metabolism and life, so the fetal heart beats and circulates blood to provide oxygen and nutrients to the developing human. Without a heartbeat, we die; this is true of all humans from the sixth week onward.
Initially, the embryonic heart rate is, on average, 110 beats per minute, and it increases to approximately 170 beats per minute at nine to 10 weeks. At six weeks, the heartbeat can be detected via a transvaginal ultrasound. Doppler ultrasonography measures the movement of the beating heart. The same type of instrument is used to measure blood flow through the carotid arteries of adults. Electrocardiography measures the electrical activity of heart cells. Ultrasonography does not measure electrical activity, as it detects changes in frequency of pulses of high-frequency sound reflected off solid objects. This is the same principle used by a radar gun to bounce radar pulses off your car and detect its speed and movement; a radar gun is not measuring the electrical activity of your car’s battery.
At six weeks, the embryo’s heart is beating rhythmically to pump blood throughout the tiny body, and the heart can be easily identified and its image captured. At that age, is it exactly the same as an adult heart? Of course not, there is still more growth, development and remodeling to come, even up to and after birth, but the early human embryo has a functioning heart.
The human brain begins to form early in development. The brain and spinal cord form from a structure called the neural tube, with formation beginning around six weeks gestation. Very soon after this, more specific brain regions (forebrain, midbrain, hindbrain) form and further specialization of brain regions commences.
By the end of the seventh week, the developing human brain has identifiable right and left cerebral hemispheres. The human brain continues its development throughout gestation. During the first half of gestation, new neurons are formed at a rate of up to 250,000 neurons per minute. Human brain development continues even for years after birth; final maturation of the brain cortex does not occur until about 25 years of age. Yes, the early human embryo has a brain.
Some define courage as strength even when faced with uncertainty or imminent pain. The developing human being certainly faces uncertainty. Starting as a single-celled organism who becomes an organized, interacting community of over 30 trillion cells, growing and forming a multitude of specialized organs and tissues in mere weeks, the complexity of the developmental pathway can seem miraculous at times.
Moreover, facing that uncertainty implies developing conscious awareness. Modern science has shown that the organs have developed and neural connections are present by 15 weeks. The technological and medical advances in human embryology have made it possible to directly observe fetal behavior. Studies now demonstrate that fetuses as young as 12 weeks show conscious awareness of their environment, sensory discrimination, sociality and even planning of intentional physical movements and interactions.
As far as imminent pain, the scientific evidence indicates that a human fetus can indeed experience pain much earlier than previously believed. When the science is objectively reviewed, “Overall, the evidence, and a balanced reading of that evidence, points toward an immediate and unreflective pain experience mediated by the developing function of the nervous system from as early as 12 weeks.” It is definitely time to reconsider any previous suppositions about fetal pain experience and consciousness. A developing human being certainly does show courage.
It should be self-evident that the developing human being has a home: the womb. This protective, nurturing environment provides a valued home during the nine months of gestation. But the obvious value of this home goes beyond the usual assumptions and benefits both mom and the developing human. A new scientific review paper details how cells exchanged between mom and baby across the womb during pregnancy create a lifelong bond between a mother and her child right down to the cellular level, a bond that contributes to the survival of both individuals.
If I only had a heart, I could see the value in letting a young human develop her own heart, brain and courage, completing the journey in what should be the safest of homes. For a view of the entire journey of the developing human being, see the Voyage of Life.