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Preimplantation Genetic Diagnosis

Preimplantation genetic diagnosis (PGD) involves testing for specific genetic conditions prior to the implantation of an embryo in the uterine wall. This form of genetic screening has been made possible by the growth of in-vitro fertilization (IVF) technology, which allows for the early stages of development to occur in a laboratory dish rather than in vivo. The purpose of PGD is to identify what are considered to be abnormal embryos in order to select the most desirable embryos for implantation.

Format: Articles

Subject: Technologies, Reproduction

Amniocentesis Prior to 1980

The extraembryonic membranes that surround and originate from the embryos of vertebrates such as birds, reptiles, and mammals are crucial to their development. They are integral to increasing the surface area of the uterus, forming the chorion (which in turn produces the placenta) and the amnion, respectively. The amnion will ultimately surround the embryo in a fluid-filled amniotic cavity. This amniotic fluid, which cushions and protects the fetus and helps prevent the onset of labor, is sampled in amniocentesis to screen for genetic diseases.

Format: Articles

Subject: Processes, Reproduction

Johannes Holtfreter (1901-1992)

Johannes Holtfreter made important discoveries about the properties of the organizer discovered by Hans Spemann. Although he spent much time away from the lab over many years, he was a productive researcher. His colleagues noted that the time he spent away helped revitalize his ideas. He is credited with the development of a balanced salt medium to allow embryos to develop; the discovery that dead organizer tissue retains inductive abilities; and the development of specification, competence, and distribution of fate maps in the developing frog embryo.

Format: Articles

Subject: People

Jan Swammerdam (1637-1680)

Jan Swammerdam, known as the founder of the preformation theory based on his extensive research on insect development, was born on 12 February 1637 in Amsterdam, the Netherlands, to Baertje Jans Corvers and Jan Jacobszoon Swammerdam. He began medical school on 11 October 1661 at the University of Leiden. A few of his classmates included Regnier de Graaf, Frederik Ruysch, Niels Stensen (Nicolaus Steno), and Robertus Padtbrugge. Padtbrugge would later join the East India Company and send Swammerdam exotic animals.

Format: Articles

Subject: People

Warren Tay (1843–1927)

The arterial switch operation, also called the Jatene procedure, is an operation in which surgeons redirect the flow of blood through abnormal hearts. In 1975, Adib Jatene conducted the first successful arterial switch operation on a human infant. The arterial switch operation corrects a condition called transposition of the great arteries, abbreviated TGA, also called transposition of the great vessels, abbreviated TGV. TGA occurs when the pulmonary artery, which supplies deoxygenated blood to the lungs, and the aorta, which takes oxygenated blood to the body, are switched, or transposed.

Format: Articles

Subject: Technologies

George Nicholas Papanicolaou (1883–1962)

George Nicholas Papanicolaou developed the Pap test in the United States during the twentieth century. The Pap test is a diagnostic procedure used to test for cervical cancer in women. Papanicolaou’s work helped improve the reproductive health of women by providing an effective means of identifying precancerous cells and improving the likelihood of early treatment and survival of cervical cancer.

Format: Articles

Subject: People, Reproduction

Ephraim McDowell (1771-1830)

Ephraim McDowell was an US abdominal surgeon who in 1809 performed one of the first successful ovarian surgeries. McDowell conducted his medical practice in Danville, Kentucky, where he used novel methods of ovariotomy to remove a twenty-two and a half pound ovarian tumor from his patient, Jane Crawford. At the time, surgeons performed ovariotomies by making an incision into each patient’s ovary to remove a mass. However, their patients often died from infection or blood loss.

Format: Articles

Subject: People

Eugenical Sterilization in the United States (1922), by Harry H. Laughlin

Eugenical Sterilization in the United States is a 1922 book in which author Harry H. Laughlin argues for the necessity of compulsory sterilization in the United States based on the principles of eugenics. The eugenics movement of the early twentieth century in the US focused on altering the genetic makeup of the US population by regulating immigration and sterilization, and by discouraging interracial procreation, then called miscegenation.

Format: Articles

Subject: Outreach, Legal, Ethics, Publications

Edgar Allen (1892–1943)

Edgar Allen identified and outlined the role of female sex hormones and discovered estrogen in the early 1900s in the US. In 1923, Allen, through his research with mice, isolated the primary ovarian hormone, later renamed estrogen, from ovarian follicles and tested its effect through injections in the uterine tissues of mice. Allen’s work on estrogen, enabled researchers to further study hormones and the endocrine system.

Format: Articles

Subject: People

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

Beatrice Mintz (1921- )

Beatrice Mintz is a brilliant researcher who has developed techniques essential for many aspects of research on mouse development. She produced the first successful mouse chimeras and meticulously characterized their traits. She has worked with various cancers and produced viable mice from the cells of a teratoma. Mintz participated in the development of transgenic mice by the incorporation of foreign DNA into a mouse genome.

Format: Articles

Subject: People

2D Obstetric Ultrasound

The development of the obstetric ultrasound has allowed physicians and embryologists to obtain a clear picture of the developing human embryo and fetus during pregnancy. Obstetric ultrasonography, often referred to as ultrasound, is a technology that uses sound waves to produce images of structures inside the human body. A handheld probe emits sound waves, which are reflected back by the different structures within the body.

Format: Articles

Subject: Technologies, Reproduction

“Maternal and Perinatal Outcomes Associated with a Trial of Labor after Prior Cesarean Delivery” (2004), Mark B. Landon et al.

In 2004 Mark Landon and his colleagues in the United States published “Maternal and Perinatal Outcomes Associated with a Trial of Labor after Prior Cesarean Delivery,” which compared the risks of vaginal delivery and cesarean section for delivery of a fetus after a previous cesarean delivery. During a cesarean section, a physician surgically removes a fetus from a pregnant woman through an incision in her abdomen. By the late 1900s, most clinical guidelines viewed attempting a vaginal birth after a previous cesarean delivery as a reasonable option for most women.

Format: Articles

Subject: Publications

Images of Embryos in Life Magazine in the 1950s

Embryonic images displayed in Life magazine during the mid-twentieth century serve as a representation of technological advances and the growing public interest in the stages of embryological development. These black-and-white photographs portray skeletal structures and intact bodies of chicken embryos and human embryos and fetuses obtained from collections belonging to universities and medical institutions.

Format: Articles

Subject: Outreach, Publications, Reproduction

"Formation of Genetically Mosaic Mouse Embryos and Early Development of Lethal (t12/t12)-Normal Mosaics" (1964), by Beatrice Mintz

The paper "Formation of Genetically Mosaic Mouse Embryos and Early Development of Lethal (t12/t12)-Normal Mosaics," by Beatrice Mintz, describes a technique to fuse two mouse embryos into a single embryo. This work was published in the Journal of Experimental Zoology in 1964. When two embryos are correctly joined before the 32-cell stage, the embryo will develop normally and exhibit a mosaic pattern of cells as an adult.

Format: Articles

Subject: Experiments

“Kangaroo Care Is Effective in Diminishing Pain Response in Preterm Neonates” (2003), by Celeste Johnston, Bonnie Stevens, Janet Pinelli, Sharyn Gibbins, Francoise Filion, Anne Jack, Susan Steele, Kristina Boyer, and Annie Veilleux

In the 2003 article “Kangaroo Care Is Effective in Diminishing Pain Response in Preterm Neonates”, Celeste Johnston, Bonnie Stevens, Janet Pinelli, and their colleagues evaluate the effectiveness of the Kangaroo Mother Care position in decreasing the pain response of preterm infants who undergo a heel lance procedure for blood collection. Kangaroo Mother Care is a method of treatment for premature and low birth weight infants that involves exclusive breastfeeding and skin-to-skin contact between a mother and her infant in what is called the kangaroo position.

Format: Articles

Subject: Publications

John Philip Trinkaus (1918-2003)

John Philip Trinkaus studied the processes of cell migration and gastrulation, especially in teleost fish, in the US during the twentieth century. Called Trink by his friends, his social confidence and work ethic combined to make him a prolific and decorated developmental biologist. His scientific contributions included investigations of several different aspects of embryology.

Format: Articles

Subject: People

George Richard Tiller (1941-2009)

George Richard Tiller, a doctor who performed abortions in Wichita, Kansas, was shot to death on 31 May 2009 by Scott Roeder. As the director of one of only a small number of clinics in the US that performed legal late-term abortions, Tiller was a target for anti-abortion activists. Though Tiller lived and worked in Kansas, his work agitated anti-abortion groups and fueled the controversy surrounding abortion at a national level. Tiller's life and death fueled the abortion debate in the US.

Format: Articles

Subject: People, Reproduction

Stanley Alan Plotkin's Development of a Rubella Vaccine (1969)

In the US during the late 1960s, Stanley Alan Plotkin, John D. Farquhar, Michael Katz, and Fritz Buser isolated a strain of the infectious disease rubella and developed a rubella vaccine with a weakened, or attenuated, version of the virus strain. Rubella, also called German measles, is a highly contagious disease caused by the rubella virus that generally causes mild rashes and fever. However, in pregnant women, rubella infections can lead to developmental defects in their fetuses.

Format: Articles

Subject: Experiments

Roman Catholic Church Quickening

Although the concept of quickening was not developed initially by the Roman Catholic Church, much of their histories are intertwined. Quickening, the point at which a pregnant woman can first feel the movements of the growing embryo or fetus, has long been a pivotal moment in pregnancy. Historically, it has also been a pivotal moment for law and the Church in deciding the criminal and religious sanctions for women who intentionally procured an abortion.

Format: Articles

Subject: Religion

Sidney Q. Cohlan (1915-1999)

Sidney Q. Cohlan studied birth defects in the US during the twentieth century. Cohlan helped to discover that if a pregnant woman ate too much vitamin A her fetus faced a higher than normal risk of teratogenic effects, such as cleft palate. A teratogen is a substance that causes malformation of a developing organism. Cohlan also identified the teratogenic effects of several other substances including a lack of normal magnesium and prenatal exposure to the antibiotic tetracycline.

Format: Articles

Subject: People

The Business of Being Born (2008)

In 2008, Barranca Productions released a documentary called The Business of Being Born, detailing the topic of childbirth. Ricki Lake and Abby Epstein produced and directed the documentary. The documentary explores pregnancy related healthcare in the US, including the history of midwives and obstetrics. The film also discusses potential consequences of medicalized childbirth common in the twenty-first century. The Business of Being Born provides viewers with information about home-births, midwives, and the positive and negative aspects of going to the hospital for childbirth.

Format: Articles

Subject: Outreach

Leonardo da Vinci's Embryological Annotations

Among his myriad scientific and artistic contributions, Leonardo da Vinci's work in embryology was groundbreaking. He observed and diagramed the previously undemonstrated position of the fetus in the womb with detailed accompanying annotations of his observations. Leonardo was highly paranoid of plagiarism and wrote all of his notes in mirror-like handwriting laden with his own codes, making his writing difficult to discern and delaying its impact.

Format: Articles

Subject: Publications

Embryonic Sex Differentiation and Sex Hormones (1947), by Carl R. Moore

In 1947, Carl Richard Moore, a researcher at the University of Chicago, in Chicago, Illinois, wrote Embryonic Sex Differentiation and Sex Hormones, which was published in the same year as a first-edition monograph. In the book, Moore argues that regulation of sex differentiation in mammals is not controlled by sex hormones secreted by embryonic sex organs (gonads), but is controlled by non-hormonal genetic factors.

Format: Articles

Subject: Publications, Experiments

Intrauterine Insemination

Intrauterine insemination (IUI), also known as artificial insemination, is one of the earliest and simplest assisted reproductive technologies (ART). With this technique, sperm from either a partner or donor (such as from a sperm bank) is inserted with a syringe into the woman's vagina during ovulation to increase the probability that fertilization will occur and lead to pregnancy.

Format: Articles

Subject: Technologies, Reproduction