Fetal Development

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Paul Stark, a member of Minnesota Citizens Concerned for Life, wrote an opinion piece at LifeNews.com (10/8/15)and stated, “Before deciding how we ought to treat the unborn – a moral question – we must first be clear about what the unborn is. This is a scientific question, and it is answered with clarity by the science of human embryology.”Stark wrote that the facts of reproduction are clear. At fertilization, the sperm and egg cease to exist. ‘Fertilized egg’is an inaccurate term. A zygote – a single cell with 46 chromosomes (23 from each parent) is what exists. This is the point of conception – the beginning of a new human organism. Zygote, embryo and fetus refer to the developmental stages of a human being.Stark continued by pointing out the “four features of the unborn (i.e., the human zygote, embryo or fetus)[which] are relevant to his/her status as a human being.First, the unborn is living. She meets all the biological criteria for life: metabolism, cellular reproduction and reaction to stimuli. Moreover, she is clearly growing, and dead things (of course) don’t grow. Second, the unborn is human. She possesses a human genetic signature that proves this beyond any doubt…Living things do not become something different as they grow and mature; rather, they develop the way that they do precisely because of the kind of being that they are. Third, the unborn is genetically and functionally distinct from (though dependent on and resting inside of) the pregnant woman. Her growth and maturation are internally directed, and her DNA is unique and different from that of any other cell in the woman’s body. She develops her own arms, legs, brain, central nervous system, etc.To say that a fetus is part of the pregnant woman’s body is to say that the woman has four arms and four legs….Fourth, the unborn is a whole or complete (though immature) organism. That is, she is not a mere part of another living thing, but is her own organism – an entity whose parts work together in a self-integrated fashion to bring the whole to maturity. Her genetic information is fully present at conception, determining to a large extent her physical characteristics (including sex, eye color, skin color, bone structure, etc.); she needs only a suitable environment and nutrition to develop herself through the different stages of human life. Thus, the unborn is a distinct, living and whole human organism – a full-fledged member of the species homo sapiens, like you and me, only at a much earlier stage in her development. She is a human being.”Leading scientists and embryology textbooks confirm this fact. Stark acknowledged that the texts and individuals could be cited “ad nauseam”. One of the most widely used embryology texts, The Developing Human: Clinically Oriented Embryology by Keith L. Moore and T.V.N. Persaud, states, “Human development begins at fertilization when a male gamete or sperm (spermatozoon) unites with a female gamete or oocyte (ovum) to form a single cell – a zygote.This highly specialized, totipotent cell marked the beginning of each of us as a unique individual.” Dr. MichelineMatthews-Roth of Harvard Medical School stated, “It is scientifically correct to say that an individual human life begins at conception when egg and sperm join to form the zygote, and this developing human is always a member of our species in all stages of its life.” After hearing expert testimony, the official report of a 1981 US Senate judiciary subcommittee stated, “Physicians, biologists, and other scientists agree that conception marks the beginning ofthe life of a human being – a being that is alive and is amember of the human species. There is overwhelming agreement on this point in countless medical, biological,and scientific writings…no witness…raised any evidence to to refute the biological fact that from the moment of conception there exists a distinct individual being who is alive and is of the human species.”Stark stated that the claim “no one knows when life begins” is repeated so often that it must be addressed. He acknowledges that there is “debate about when a human being becomes (if she isn’t by nature) valuable and deserving of full moral respect.” However, “the strictly biological matter is clear…The life of a human being…begins at conception.” The argument that sperm and eggs are also human because they have the potential to become a child is “bad biology. The sperm and egg are simply parts of larger organisms. When they unite they cease to be and something new comes into existence: the zygote, whole organism with the active capacity to develop into a mature member of its species, given only a suitable environment and nutrition. Each of us was once a zygote, but none of us was ever a sperm or egg.”There are those who compare the zygote or embryo to other somatic cells which are human, living and possess a full genetic code. But these cells are not actual human beings. There is a critical difference between body cells such a skin cells and a zygote or embryo. The zygote or embryo “is a distinct and complete individual whose parts work together in a coordinated fashion to develop thewhole to maturity.” Skin cells and other somatic cells“function as mere parts of a larger organism.” Another argument that is made is that since very early embryos can split into two distinct embryos (twinning) then the early embryo is not a unitary individual. Stark noted that if flatworm is cut in half, or an organism is cloned, “a single organism gives rise to two distinct organisms. In both cases the original entity is a unitary, self-integrating, whole individual. The scientific evidence shows that the embryo likewise functions as its own organism, from the zygote stage forward, regardless of whether twinning occurs.”There are also those who claim that human life doesn’t begin until the unborn develops a brain. Stark argued,“brain death is accepted as a criterion only because it signals the end of the body’s ability to function as an integrated organism, for which the brain, in older humans, is essential. After brain death there is no longer a unitary organism. By contrast, the embryo is a unitary organism from conception, actively developing to the next stage of human life. The brain, at this earliest stage, is not yet necessary for her to function as such.”Stark concluded, “Because the scientific facts are clear,the permissibility of taking human life hinges on a moral question. Do all human beings merit full moral respect and protection, …or only some?” Submitted by Regina CarbonaroPaul Stark, a member of Minnesota Citizens Concerned for Life, wrote an opinion piece at LifeNews.com (10/8/15)and stated, “Before deciding how we ought to treat the unborn – a moral question – we must first be clear about what the unborn is. This is a scientific question, and it is answered with clarity by the science of human embryology.”Stark wrote that the facts of reproduction are clear. At fertilization, the sperm and egg cease to exist. ‘Fertilized egg’is an inaccurate term. A zygote – a single cell with 46 chromosomes (23 from each parent) is what exists. This is the point of conception – the beginning of a new human organism. Zygote, embryo and fetus refer to the developmental stages of a human being.Stark continued by pointing out the “four features of the unborn (i.e., the human zygote, embryo or fetus)[which] are relevant to his/her status as a human being.First, the unborn is living. She meets all the biological criteria for life: metabolism, cellular reproduction and reaction to stimuli. Moreover, she is clearly growing, and dead things (of course) don’t grow. Second, the unborn is human. She possesses a human genetic signature that proves this beyond any doubt…Living things do not become something different as they grow and mature; rather, they develop the way that they do precisely because of the kind of being that they are. Third, the unborn is genetically and functionally distinct from (though dependent on and resting inside of) the pregnant woman. Her growth and maturation are internally directed, and her DNA is unique and different from that of any other cell in the woman’s body. She develops her own arms, legs, brain, central nervous system, etc.To say that a fetus is part of the pregnant woman’s body is to say that the woman has four arms and four legs….Fourth, the unborn is a whole or complete (though immature) organism. That is, she is not a mere part of another living thing, but is her own organism – an entity whose parts work together in a self-integrated fashion to bring the whole to maturity. Her genetic information is fully present at conception, determining to a large extent her physical characteristics (including sex, eye color, skin color, bone structure, etc.); she needs only a suitable environment and nutrition to develop herself through the different stages of human life. Thus, the unborn is a distinct, living and whole human organism – a full-fledged member of the species Homo sapiens, like you and me, only at a much earlier stage in her development. She is a human being.”Leading scientists and embryology textbooks confirm this fact. Stark acknowledged that the texts and individuals could be cited “ad nauseam”. One of the most widely used embryology texts, The Developing Human: Clinically Oriented Embryology by Keith L. Moore and T.V.N. Persaud, states, “Human development begins at fertilization when a male gamete or sperm (spermatozoon) unites with a female gamete or oocyte (ovum) to form a single cell – a zygote.This highly specialized, totipotent cell marked the beginning of each of us as a unique individual.” Dr. MichelineMatthews-Roth of Harvard Medical School stated, “It is scientifically correct to say that an individual human life begins at conception, when egg and sperm join to form the zygote, and this developing human is always a member of our species in all stages of its life.” After hearing expert testimony, the official report of a 1981 US Senate judiciary subcommittee stated, “Physicians, biologists, and other scientists agree that conception marks the beginning of the life of a human being – a being that is alive and is a member of the human species. There is overwhelming agreement on this point in countless medical, biological, and scientific writings…no witness…raised any evidence to refute the biological fact that from the moment of conception there exists a distinct individual being who is alive and is of the human species.”Stark stated that the claim “no one knows when life begins” is repeated so often that it must be addressed. He acknowledges that there is “debate about when a human being becomes (if she isn’t by nature) valuable and deserving of full moral respect.” However, “the strictly biological matter is clear…The life of a human being…begins at conception.” The argument that sperm and egg are also human because they have the potential to become a child is “bad biology. The sperm and egg are simply parts of larger organisms. When they unite they cease to be and something new comes into existence: the zygote, whole organism with the active capacity to develop into a mature member of its species, given only a suitable environment and nutrition. Each of us was once a zygote, but none of us was ever a sperm or egg.”There are those who compare the zygote or embryo to other somatic cells which are human, living and possess a full genetic code. But these cells are not actual human beings. There is a critical difference between body cells such as skin cells and a zygote or embryo. The zygote or embryo “is a distinct and complete individual whose parts work together in a coordinated fashion to develop the whole to maturity.” Skin cells and other somatic cells“function as mere parts of a larger organism.” Another argument that is made is that since very early embryos can split into two distinct embryos (twinning) then the early embryo is not a unitary individual. Stark noted that if aflatworm is cut in half, or an organism is cloned, “a singleorganism gives rise to two distinct organisms. In both cases the original entity is a unitary, self-integrating, whole individual. The scientific evidence shows that the embryo likewise functions as its own organism, from the zygote stage forward, regardless of whether twinning occurs.”There are also those who claim that human life doesn’tbegin until the unborn develops a brain. Stark argued,“brain death is accepted as a criterion only because it signals the end of the body’s ability to function as an inte-grated organism, for which the brain, in older humans, isessential. After brain death there is no longer a unitaryorganism. By contrast, the embryo is a unitary organism from conception, actively developing to the next stage of human life. The brain, at this earliest stage, is not yet nec-essary for her to function as such.”Stark concluded, “Because the scientific facts are clear,the permissibility of taking human life hinges on a moral question. Do all human beings merit full moral respect and protection, …or only some?” Submitted by Regina Carbonaro

An Abstract authored by Denise Araujo Lapa Pedreira entitled “Advances in fetal surgery” appeared in the Jan/Mar 2016 issue of Einstein (São Paulo) vol.14 no.1. Her purpose was to discuss “the main advances in fetal surgical therapy aiming to inform healthcare professionals about the state-of-the-art techniques and future challenges in this field.” She discusses “the necessary steps of technical evolution from the initial open fetal surgery approach until the development of minimally invasive techniques of fetal endoscopic surgery (fetoscopy).” The author notes that currently the following “fetal malformations can be treated with fetal surgery…monochorionic twin gestation complications (twin transfusion syndrome, acardiac twin,isolated intrauterine growth restriction, etc.), congenital diaphragmatic hernia (an intratracheal balloon is placed using fetal bronchoscopy), constrictive amniotic bands, lower urinary tract obstruction and, more recently, myelomeningocele” (the most serious form of spina bifida).“Fetal surgery began in the 1980s via open surgery(maternal laparotomy, followed by hysterectomy with direct exposure of the fetus) and was gradually replaced by a less invasive surgical technique named fetoscopy, where ultrasound guides the entrance of a video camera inside the uterus. In the beginning, fetos-copy was carried out only in amniotic fluid medium,using a single port to access the uterine cavity andusing an endoscopic scope with a working channelwhere a laser fiber can be fitted for the coagulation ofblood vessels, where micro catheters go through forthe balloon insertion, as well as, small bipolarforceps.”The author notes that the “fluid medium poses limi-tations for more complex surgeries that require dissec-tion and suture. Images acquired in fluid medium havelower quality than in the aerial medium, and if bleeding occurs, the hemorrhagic fluid does not allow anadequate imaging”. This can result in the procedurenot being completed. Also, movement of the fetus from an “ideal position” can limit the ability to com-plete the procedure. The author stated that “to performfetoscopy in the aerial medium became crucial to theadvances in fetal surgery.”In 2011, the Management of MyelomeningoceleStudy (MOMS) used open surgery for fetal repair.Drs. Adzick et al concluded that “prenatal surgery formyelomeningocele reduced the need for shunting andimproved motor outcomes at 30 months, but was asso-ciated with maternal and fetal risks” (increased risk ofpreterm delivery, uterine dehiscence (rupture), needfor blood transfusions, pulmonary edema). Pedreiranotes that “after a c-section, hysterorrhaphy can healwithout tension, because the baby is already out,while in the open surgery, the fetus remains and con-tinues to grow – therefore the hysterorrhaphy remainsunder constant and progressive tension.”Pedreira noted that “despite these risks, open fetalsurgery became the gold standard to treat mye-lomeningocele”. The search for minimally invasivetechniques that would increase maternal safety con-tinued. In 2014, T. Kohl at the German Center forFetal Surgery and Minimally Invasive Therapy re-ported that a study which included 51 human fetusesemploying “percutaneous (through the skin) minimal-access fetoscopic closure of spina bifida aperta(SBA)” resulted in “a high rate of technical success,regardless of placental or fetal position.” All fetusessurvived the surgery. One very early preterm deliverya week after surgery resulted in immediate death. An-other died from “an unsuspected case of trisomy 13,and there were two infant deaths from Chiari-II mal-formation.” (Ultrasound Obstet Gynecol, 2014 Nov)Pedreira stated that Kohl et al in Germany and hergroup in Brazil were the only groups (at the time ofpublication in 2016) that were pursuing “an entirelypercutaneous endoscopic approach for the prenataltreatment of myelomeningocele…Both groups usefetoscopy with partial carbon dioxide insufflation, butdifferent surgical techniques for the repair itself.” Shenotes that just as in the “transition between perform-ing surgery using laparotomy to using the laparoscop-ic approach, it was necessary to develop new surgicaltechniques, new instruments, trocars access, closuredevices, etc.” She notes that “the German techniquehas achieved neurological developmental results thatare quite similar to the results of the MOMS study,but with minimal maternal morbidity. The Braziliantechnique, (SAFER – Skin-over-biocellulose for An-tenatal Fetoscopic Repair) has obtained superior neu-rologic results compared to the MOMS study.” How-ever, she warns that the results are preliminary (23cases so far). In addition, “because three ports areneeded to access the uterine cavity, the mean gesta-tional age of delivery is slightly inferior, and thepremature rupture of membrane rate is superior [to]the results of the MOMS study.”Pedreira concluded, “We believe that further tech-nical development in the near future will confirm ifthis new technique is not only SAFER to the mother,but also better [for] the fetus.”Submitted by Regina Carbonaro 516-243-1435

 

First TrimesterDuring the first 8 weeks, an unborn child is called anembryo. The embryo grows 10,000 times in size fromconception through the first 4 weeks. The vital organcalled the placenta has vessels from the mother to theunborn child that intertwine without joining. This organis the source of nourishment. The heart begins to pulsateand pump blood during the 3rd week. By the end of 4weeks all major systems and organs begin to form. Theneural tube (which becomes the brain and spinal cord),the digestive system, and the heart circulatory systembegin to form. The embryo has an independent oxygendiffusion system. The beginnings of the eyes and earsare developing. Tiny limb buds which will develop intoarms and legs appear. By eight weeks, all major bodysystems including the circulatory, nervous, digestive andurinary systems continue to develop and function. Thecentral nervous system is now functioning, and 40 mus-cle sets begin their first exercises. The embryo is takingon a human shape, although the head is larger in propor-tion to the rest of the body. The mouth is developingtooth buds, which will become baby teeth. The eyes,nose, mouth and ears are becoming more distinct. Armsand legs are clearly visible. Fingers and toes are stillwebbed but can be clearly distinguished. The fetal heart-beat can be heard using a Doppler. Bones, nose and jawsare rapidly developing. The embryo is in constant mo-tion, but cannot be felt by the mother. The unborn childreacts to touch.After 8 weeks, the unborn child is referred to as afetus (Latin for ‘little one’). At 8 weeks, the fetus is 1 to1 1/2 inches long and all major organs and systems havebeen formed. During weeks 9 – 12, the external genitalorgans are developed, fingernails and toenails appear,eyelids are formed, fetal movement increases, the armsand legs are fully formed, and the larynx begins to formin the trachea. The unborn child can now squint,swallow, move the tongue and sleeps and awakens.There is now a distinct set of fingerprints. Sensitive totouch, the unborn child will now grasp an object placedin the palm. The fetus breathes amniotic fluid to helpdevelop and strengthen the respiratory system, butoxygen is supplied through the umbilical cord. The mostvulnerable time for the unborn child is during the first12 weeks. All the major organs and body systems aredeveloping and can be damaged by exposure to drugs,German measles, radiation, tobacco and chemical andtoxic substances. Although all the organs and bodysystems are fully formed by the end of 12 weeks, thefetus cannot survive independently.Second TrimesterNow that all the major organs and systems have formed,the following 6 months are spent growing. By 4 months,the unborn child is 6-7 inches long. The mother may feelmovement. The unborn child’s brain is maturing, aprocess that will continue long past birth. The eyelids aresealed shut and will re-open at 7 months. Taste buds areworking. 300 quarts of fluid a day pass through theumbilical cord. Fine hair is growing on the head, eye-brows and eyelashes. Facial expressions can be seen.Rapid eye movements (REMs), a sign of dreaming canbe recorded. At the end of 5 months, the unborn child is10-12 inches long and weighs about 1 lb. Babies born atthis age have survived. The 20th week marks the halfwaypoint of the pregnancy. Pain receptors (nociceptors) arepresent throughout the unborn child’s entire body by 20weeks. After 20 weeks, the unborn child reacts to stimulithat would be recognized as painful if applied to anadult. In the unborn child, application of such painfulstimuli is associated with significant increases in stresshormones (the stress response). Subjection to painfulstimuli is associated with long-term harmful neurodevel-opmental effects, such as altered pain sensitivity and,possibly, emotional, behavioral, and learning disabilitieslater in life. Fetal anesthesia is routinely administeredduring surgery on unborn children and is associated witha decrease in stress hormones compared to their levelwhen painful stimuli are applied without anesthesia.There is documented reaction of unborn children topainful stimuli. Fetal surgeons have found it necessary tosedate the unborn child in order to prevent thrashingabout in reaction to invasive surgery. There is substantialmedical evidence that an unborn child is capable ofexperiencing pain by 20 weeks. By the 24th week, theunborn child can be 11-14 inches long and weighs about1 3/4 lbs. Oil and sweat glands function and helpregulate body temperature. Vernix caseosa, a creamywhite substance protects the delicate skin from amnioticfluid and from scratches as the unborn child twists andturns. The unborn child responds to sound. The lungs arefairly well developed and the unborn child stands a goodchance of survival if born at this time.Third TrimesterIn the 7th month, the unborn child uses 4 senses. Theeyelids open and close and the eyes look around, and theunborn child can taste, touch, cough and hiccup. Thegrip is even stronger now than it will be after birth. Anti-bodies are received from the mother that provide immun-ity to a wide variety of diseases. The unborn child is now14-17 inches and weighs 2 1/2 – 3 lbs. The bones of theskull remain soft to allow the unborn child to passthrough the birth canal. Fat deposits under the skin elimi-nate wrinkling and will provide warmth after birth. Atthe end of 8 months the unborn child is about 16 – 18inches long and weighs 4 1/2 – 5 1/2 lbs. In the 9thmonth, the unborn child usually shifts to a head-downposition in preparation for birth. At 9 months, the unbornchild averages about 19 inches and 7 lbs., but this varieswidely. The human growth process will continue formany years after birth.

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