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Evans v. People of the State of New York [Brief] (1872)

Attempts by the New York legislature to make abortion a crime regardless of the stage of gestation were permanently frustrated because the court decided that manslaughter cannot occur until the law recognizes a living being in gestation and that only happens after quickening.

Format: Articles

Subject: Legal, Reproduction

Homunculus

The term homunculus is Latin for "little man." It is used in neurology today to describe the map in the brain of sensory neurons in each part of the body (the somatosensory homunculus). An early use of the word was in the 1572 work by Paracelsus regarding forays into alchemy, De Natura Rerum, in which he gave instructions in how to create an infant human without fertilization or gestation in the womb. In the history of embryology, the homunculus was part of the Enlightenment-era theory of generation called preformationism.

Format: Articles

Subject: Processes

Methylmercury and Human Embryonic Development

Methylmercury (MeHg) is an organic form of mercury that can damage the developing brains of human fetuses. Women who consume methylmercury during pregnancy can bear children who have neurological issues because methylmercury has toxic effects on the nervous system during embryonic development. During the third week of gestation, the human nervous system begins to form in the embryo. During this gestational period, the embryo's nervous system is particularly susceptible to the influence of neurotoxins like methylmercury that can result in abnormalities.

Format: Articles

Subject: Reproduction, Disorders

Amniocentesis

Amniocentesis is a test used for prenatal diagnosis of inherited diseases, Rh incompatibility, neural tube defects, and lung maturity. Normally performed during the second trimester of a pregnancy, this invasive procedure allows the detection of health problems in the fetus as early as fifteen weeks gestation. Although amniocentesis does carry some significant risks, the medical community commonly accepts it as a safe and useful procedure.

Format: Articles

Subject: Technologies, Reproduction

Pope Gregory XIV (1535-1591)

Pope Gregory XIV, born Nicolo Sfondrati, reversed the bull of Pope Sixtus V, Effraenatum, under which an abortion at any time of gestation can be punished by excommunication. He supported the Aristotelian distinction between an "animated" and "unanimated" fetus, making abortion of an unanimated fetus punishable by lesser means. This decision contributed to the historical debates within the Roman Catholic Church on when a fetus has a soul, and when abortion was punishable by excommunication.

Format: Articles

Subject: People, Religion, Reproduction

Pope Pius IX (1792-1878)

Pope Pius IX, born Giovanni Maria Mastai-Ferretti, marked his contribution to the abortion debate by removing the distinction between an "animated" and "unanimated" fetus from Catholic doctrine, and established the edict that a human should be protected starting from the moment of conception onward. This proclamation made abortion at any time of gestation punishable by excommunication. Pope Pius IX's decision became Canon Law of the Catholic Church.

Format: Articles

Subject: People, Religion, Reproduction

Developmental Timeline of Alcohol-Induced Birth Defects

Maternal consumption of alcohol (ethanol) during pregnancy can result in a continuum of embryonic developmental abnormalities that vary depending on the severity, duration, and frequency of exposure of ethanol during gestation. Alcohol is a teratogen, an environmental agent that impacts the normal development of an embryo or fetus. In addition to dose-related concerns, factors such as maternal genetics and metabolism and the timing of alcohol exposure during prenatal development also impact alcohol-related birth defects.

Format: Articles

Subject: Disorders, Reproduction

Southern Gastric Brooding Frog

Object is a painted image of two southern gastric brooding frogs facing each other. The one on the left has a transparent middle to reveal tadpoles swimming inside of it. The one on the right shows a more mature juvenile crawling out of the mouth.

The Southern Gastric Brooding Frog (Rheobotrahcus silus) was a frog species that lived in Australia. It was declared extinct in 2002. Once adult males fertilized the eggs of females, the females swallowed their eggs. The stomachs of the females then functioned somewhat like wombs, protecting the eggs while they gestated. Once the eggs developed into juveniles, female frogs performed oral birth and regurgitated their young.

Format: Graphics

Subject: Organisms

Preformationism in the Enlightenment

Preformationism was a theory of embryological development used in the late seventeenth through the late eighteenth centuries. This theory held that the generation of offspring occurs as a result of an unfolding and growth of preformed parts. There were two competing models of preformationism: the ovism model, in which the location of these preformed parts prior to gestation was the maternal egg, and the spermism model, in which a preformed individual or homunculus was thought to exist in the head of each sperm.

Format: Articles

Subject: Theories

Edward Drinker Cope (1840-1897)

Edward Drinker Cope studied fossils and anatomy in the US in the late nineteenth century. Based on his observations of skeletal morphology, Cope developed a novel mechanism to explain the law of parallelism, the idea that developing organisms successively pass through stages resembling their ancestors. Others had proposed the addition of new body forms at the end of an individual organism's developed as a mechanism through which new species arose, but those proposals relied on changes in the lengths of gestation or incubation.

Format: Articles

Subject: People

Corpus Callosum Defects Associated with Fetal Alcohol Syndrome

Prenatal exposure to alcohol (ethanol) can result in a continuum of developmental abnormalities that are highly variable depending on the severity, duration, frequency, and timing of exposure during gestation. Defects of the corpus callosum (CC) have proven to be a reliable indicator of prenatal alcohol exposure as it affects the brain. Structural abnormalities of the CC occur along a continuum, like most alcohol-induced anomalies, whereby more severe prenatal exposure results in a greater expression of the abnormal trait.

Format: Articles

Subject: Disorders, Reproduction

Sir Graham Collingwood Liggins (1926-2010)

Sir Graham Collingwood Liggins devoted much of his professional life to obstetric research. Liggins demonstrated that hormones created by the fetus helped initiate labor, rather than hormones originating solely from the mother. Liggins also discovered that cortisol given to pregnant mothers helped delay premature labor, and that it increased the likelihood that premature infants would breathe normally after birth. Prior to cortisol treatment, premature infants often died of respiratory distress syndrome characterized by the inability to inflate immature lungs.

Format: Articles

Subject: People, Reproduction

Isaacson v. Horne (2013)

In the 2013 case Isaacson v. Horne, the US Court of Appeals in the Ninth Circuit ruled that Arizona House Bill (HB) 2036, which prohibited abortions after twenty weeks of gestation, was unconstitutional. The Arizona State Legislature passed the law in 2012, which was then challenged by three physicians who filed a lawsuit against the state, arguing that the law violated women's constitutionally protected rights to abortions, rights that may only be infringed once fetuses are viable outside of the womb.

Format: Articles

Subject: Legal

Congenital Rubella Syndrome (CRS)

Congenital rubella syndrome (CRS) can occur in children whose mothers contracted the rubella virus, sometimes called German measles, during pregnancy. Depending on the gestational period when the mother contracts rubella, an infant born with CRS may be unaffected by the virus or it may have severe developmental defects. The most severe effects of the virus on fetal development occur when the mother contracts rubella between conception and the first trimester.

Format: Articles

Subject: Disorders

Pre- and Post-natal Growth Deficiencies and Fetal Alcohol Syndrome

Maternal consumption of alcohol (ethanol) during pregnancy can inhibit prenatal growth, resulting in fetuses that are small for gestational age. Those prenatal growth deficiencies can have lasting consequences for early childhood development and are often reflected by low weight and stature. Those alcohol-induced pre- and post-natal growth deficiencies ("failure to thrive") are among the abnormal developmental criteria used to identify Fetal Alcohol Syndrome (FAS). FAS is characterized by minor facial abnormalities and deficiencies of the central nervous system as well.

Format: Articles

Subject: Disorders

Corticosteroids' Effect on Fetal Lung Maturation (1972), by Sir Graham Collingwood Liggins and Ross Howie

In a clinical trial from 1969 to 1972, Sir Graham Collingwood Liggins and Ross Howie showed that if doctors treat pregnant women with corticosteroids before those women deliver prematurely, then those women's infants have fewer cases of respiratory distress syndrome than do similarly premature infants of women not treated with corticosteroids. Prior to the study, premature infants born before 32 weeks of gestation often died of respiratory distress syndrome, or the inability to inflate immature lungs.

Format: Articles

Subject: Experiments

Parasitic Twins

Parasitic twins, a specific type of conjoined twins, occurs when one twin ceases development during gestation and becomes vestigial to the fully formed dominant twin, called the autositic twin. The underdeveloped twin is called parasitic because it is only partially formed, is not functional, or is wholly dependent on the autositic twin.

Format: Articles

Subject: Disorders, Reproduction

Isotretinoin (Accutane) as a Teratogen

Isotretinoin is a molecule and a byproduct (metabolite) of vitamin A, and in greater than normal amounts in pregnant women, it can cause fetal abnormalities including cleft lips, ear and eye defects, and mental retardation. Isotretinoin is commonly called by its trade name Accutane, and it's a chemical compound derived from vitamin A, or retinoic acid. Doctors prescribe isotretinoin to treat severe acne. For pregnant women, too much vitamin A or isotretinoin can also cause greater than normal rates of stillbirths and fetal disintegrations after the ninth week of gestation.

Format: Articles

Subject: Reproduction, Disorders

Human Embryonic Stem Cells

Stem cells are undifferentiated cells that are capable of dividing for long periods of time and can give rise to specialized cells under particular conditions. Embryonic stem cells are a particular type of stem cell derived from embryos. According to US National Institutes of Health (NIH), in humans, the term "embryo" applies to a fertilized egg from the beginning of division up to the end of the eighth week of gestation, when the embryo becomes a fetus. Between fertilization and the eighth week of gestation, the embryo undergoes multiple cell divisions.

Format: Articles

Subject: Processes, Reproduction

Fetal Alcohol Syndrome (FAS)

The concept Fetal Alcohol Syndrome (FAS) refers to a set of birth defects that occur in children born to mothers who abused alcohol during pregnancy. The alcohol-induced defects include pre- and post-natal growth deficiencies, minor facial abnormalities, and damage to the developing central nervous system (CNS).

Format: Articles

Subject: Disorders

Albrecht von Haller (1708-1777)

Victor Albrecht von Haller was an 18th century scientist who did extensive work in the life sciences, including anatomy and physiology, botany, and developmental biology. His embryological work consisted of experiments in understanding the process of generation, and led him to adopt the model of preformationism called ovism (the idea that the new individual exists within the maternal egg prior to conception). Haller was born in Bern, Switzerland, on 16 October, 1708. His mother was Anna Maria Engel, and his father was Niklaus Emanuel Haller.

Format: Articles

Subject: People

Edward Drinker Cope's Law of Acceleration of Growth

The Law of Acceleration of Growth is a theory proposed by Edward Drinker Cope in the US during the nineteenth century. Cope developed it in an attempt to explain the evolution of genera by appealing to changes in the developmental timelines of organisms. Cope proposed this law as an additional theory to natural selection.

Format: Articles

Subject: Theories

Effects of Prenatal Alcohol Exposure on Cardiac Development

A variety of developmental defects occur as a result of prenatal exposure to alcohol (ethanol) in utero. In humans, those defects are collectively classified as Fetal Alcohol Spectrum Disorders, with Fetal Alcohol Syndrome (FAS) representing the more severe defects. FAS is defined by pre- and post-natal growth retardation, minor facial abnormalities, and deficiencies in the central nervous system (CNS). In addition to those defects, prenatal exposure to alcohol impacts cardiogenesis, the developmental stage of heart formation.

Format: Articles

Subject: Disorders, Reproduction

"Interspecific Chimeras in Mammals: Successful Production of Live Chimeras Between Mus musculus and Mus caroli" (1980), by Janet Rossant and William I. Frels

In 1980 Janet Rossant and William I. Frels published their paper, "Interspecific Chimeras in Mammals: Successful Production of Live Chimeras Between Mus musculus and Mus caroli," in Science. Their experiment involved the first successful creation of interspecific mammalian chimeras. Mammalian chimeras are valuable for studying early embryonic development. However, in earlier studies, clonal analysis was restricted by the lack of a cell marker, present at all times, that makes a distinction between the two parental cell types in situ.

Format: Articles

Subject: Experiments

Social Implications of Non-Invasive Blood Tests to Determine the Sex of Fetuses

By 2011, researchers in the US had established that non-invasive blood tests can accurately determine the gender of a human fetus as early as seven weeks after fertilization. Experts predicted that this ability may encourage the use of prenatal sex screening tests by women interested to know the gender of their fetuses. As more people begin to use non-invasive blood tests that accurately determine the sex of the fetus at 7 weeks, many ethical questions pertaining to regulation, the consequences of gender-imbalanced societies, and altered meanings of the parent-child relationship.

Format: Articles

Subject: Reproduction, Ethics, Legal

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