Embryo Project Encyclopedia Articles

In Australia in the 1940s, Norman McAlister Gregg observed a connection between pregnant women who contracted the rubella virus, or German measles, and cataract formation in their children's eyes. Gregg published his findings in the 1941 article Congenital Cataract following German Measles in the Mother in Transactions of the Ophthalmological Society of Australia. In the article, Gregg analyzed seventy-eight cases of congenital cataracts and suggested that the mothers' environmental factors could cause birth defects, otherwise known as teratogenic effects. Gregg's paper on the teratogenic effects of an environmental agent, the rubella virus, changed the study of birth defects to include viruses as potential causes or teratogens.

Possums is a 174-page book consisting of a series of essays written about the Virginia opossum (Didelphis virginiana), the only living marsupial in the US. The essays were written by Carl Gottfried Hartman, an embryologist at the Carnegie Institute of Washington (CIW), in Baltimore, Maryland, who also worked with another mammal, the rhesus monkey. Possums was published in 1952 by Hartman's alma mater, the University of Texas at Austin (UT). Beginning in 1913, while as a graduate student, and later as an instructor at UT, Hartman captured and raised opossums. He was one of the first zoologists to study the intricacies of opossum embryology, leading to an account of the embryology and reproductive physiology of a mammal from the wild, rather than of a mammal bred exclusively for laboratory research. Possums culminated Hartman's studies of the marsupial.

In 2011, fetal researcher Vivette Glover published “Annual Research Review: Prenatal Stress and the Origins of Psychopathology: An Evolutionary Perspective,” hereafter, “Prenatal Stress and the Origins of Psychopathology,” in the Journal of Child Psychology and Psychiatry. In that article, Glover explained how an evolutionary perspective may be useful in understanding the effects of fetal programming. Fetal programming is a hypothesis that attempts to explain how factors during pregnancy can affect fetuses after birth. Researchers associate exposure to prenatal stress, or stress experienced before birth, with an increased likelihood of some mental disorders. Glover states that such outcomes may be traced back to a fetus’s response to stress during pregnancy, and that those outcomes may have been beneficial in the past. By taking an evolutionary approach toward understanding mental disorders, Glover provided insights for studying the lasting effects of maternal stress during pregnancy on children’s mental health.

Cocaine use by pregnant women has a variety of effects on the embryo and fetus, ranging from various gastro-intestinal and cardiac defects to tissue death from insufficient blood supply. Thus, cocaine has been termed a teratogen, or an agent that causes defects in fetuses during prenatal development. Cocaine is one of the most commonly used drugs in the US and it has a history of both medical and illegal recreational use. It is a drug capable of a wide array of effects on physical and mental health. Research on the teratogenic effects of cocaine began in the early 1980s, and in 1985 research on the effects of cocaine on prenatal development gained widespread attention. Since then, numerous studies have contributed to information about the detrimental impacts of maternal cocaine use on embryonic and fetal development.

Developmental Effects of Endocrine-Disrupting Chemicals in Wildlife and Humans, was published in 1993 in Environmental Health Perspectives. In the article, the authors present an account of two decades' worth of scientific research that describes the effects of certain pollutants on the health of wildlife, domestic animals, and humans, particularly when exposure takes place during embryonic growth. The term endocrine disruptor was coined in the article to describe the chemical pollutants that target the development and function of the endocrine system. Since its publication, Developmental Effects has increased research interest in endocrine disruption and has raised awareness among the general public, the scientific community, and government organizations about the effects that some chemicals may have on development and reproduction.

In 1999, Joseph Bruner, Susan B. Drummond, Anna L. Meenan, and Ina May Gaskin published, “All-fours Maneuver for Reducing Shoulder Dystocia During Labor,” in the medical journal, Obstetrical and Gynecological Survey. In the article, the authors described a birthing technique named the all-fours maneuver, or the Gaskin maneuver, and explained its effectiveness in treating fetal shoulder dystocia as compared to other maneuvers. Shoulder dystocia occurs when the neonate’s head has exited the vaginal canal, but the shoulders get stuck behind the woman’s pelvic bone, which prevents the birth of the neonate’s body. Healthcare practitioners’ use of previous methods to dislodge the fetal shoulders sometimes resulted in fetal and maternal injury. The all-fours maneuver differed from previous methods by positioning the laboring woman on her hands and knees rather than on her back. Through the article, the authors established the all-fours maneuver as a safe, fast, and effective technique for reducing shoulder dystocia.

In 1987, the World Health Organization, or WHO, took action to improve the quality of maternal health around the world through the declaration of the Safe Motherhood Initiative, or the SMI, at an international conference concerning maternal mortality in Nairobi, Kenya. Initially, the SMI aimed to reduce the prevalence of maternal mortality around the world, as over 500,000 women died during pregnancy and childbirth annually at the time of its inception, while about 98 percent of those deaths occurred in low-income countries. While WHO led the initiative, many organizations in various countries participated in additional programs in order to implement the goals of the SMI. WHO developed the SMI in order to reduce the prevalence of maternal death, developing one of the first proposals that brought attention to maternal health on a global basis at a time when global maternal mortality was high.