Embryo Project Encyclopedia

Human Papillomavirus, or HPV, is a viral pathogen that most commonly spreads through sexual contact. HPV strains 6 and 11 normally cause genital warts, while HPV strains 16 and 18 commonly cause cervical cancer, which causes cancerous cells to spread in the cervix. Physicians can detect those HPV strains, using a Pap smear, which is a diagnostic test that collects cells from the female cervix.

During the mid-twentieth century, Virginia Apgar worked as an obstetrical anesthesiologist and gave drugs to women that reduced their pain during childbirth in the US. In 1953, Apgar created a scoring system, called the Apgar score, that uses five measurements, including heart rate and breathing rate. The Apgar score evaluates newborn infants and determines who needs immediate medical attention. Apgar's work helped decrease infant mortality rates. As of 2020, hospitals around the world use the Apgar score.

Leonard Hayflick studied the processes by which cells age during the twentieth and twenty-first centuries in the United States. In 1961 at the Wistar Institute in the US, Hayflick researched a phenomenon later called the Hayflick Limit, or the claim that normal human cells can only divide forty to sixty times before they cannot divide any further. Researchers later found that the cause of the Hayflick Limit is the shortening of telomeres, or portions of DNA at the ends of chromosomes that slowly degrade as cells replicate. Hayflick used his research on normal embryonic cells to develop a vaccine for polio, and from HayflickÕs published directions, scientists developed vaccines for rubella, rabies, adenovirus, measles, chickenpox and shingles.

Leonard Hayflick in the US during the early 1960s showed that normal populations of embryonic cells divide a finite number of times. He published his results as 'The Limited In Vitro Lifetime of Human Diploid Cell Strains' in 1964. Hayflick performed the experiment with WI-38 fetal lung cells, named after the Wistar Institute, in Philadelphia, Pennsylvania, where Hayflick worked. Frank MacFarlane Burnet, later called the limit in capacity for cellular division the Hayflick Limit in 1974. In the experiment, Hayflick refuted Alexis Carrel's hypothesis that cells could be transplanted and multiplied indefinitely from a single parent cell line.

NovaSure is a device for endometrial ablation, which is a procedure that removes the endometrium, that the US Food and Drug Administration, or FDA, approved for use on 28 September 2001. Endometrium is the tissue that lines the uterus. NovaSure destroys the endometrium by sending electric beams at the endometrium. Hologic, a medical technology company concerned with women’s health, developed NovaSure to treat menorrhagia, or heavy bleeding during menstruation. Menorrhagia is a common symptom of endometriosis. Endometriosis is the growth of the endometrium outside of the uterus. While NovaSure is not a treatment that doctors use to directly treat endometriosis, the procedure may help alleviate heavy bleeding during menstruation, which may improve a patient’s quality of life as heavy menstrual bleeding is often associated with high levels of anxiety and low levels of confidence.

Telomeres are structures at the ends of DNA strands that get longer in the DNA of sperm cells as males age. That phenomenon is different for most other types of cells, for which telomeres get shorter as organisms age. In 1992, scientists showed that telomere length (TL) in sperm increases with age in contrast to most cell of most other types. Telomeres are the protective caps at the end of DNA strands that preserve chromosomal integrity and contribute to DNA length and stability. In most cells, telomeres shorten with each cell division due to incomplete replication, though the enzyme telomerase functions in some cell lines that undergo repetitive divisions to replenish any lost length and to prevent degradation. Cells, and therefore organisms, with short telomeres are more susceptible to mutations and genetic diseases. While TL increases in a subset of sperm cells and longer telomeres may prevent early disintegration of DNA, it may also prevent natural mechanisms of apoptosis, or cell death, from occurring in abnormal sperm.

Apoptosis, or programmed cell death, is a mechanism in embryonic development that occurs naturally in organisms. Apoptosis is a different process from cell necrosis, which is uncontrolled cell death usually after infection or specific trauma. As cells rapidly proliferate during development, some of them undergo apoptosis, which is necessary for many stages in development, including neural development, reduction in egg cells (oocytes) at birth, as well as the shaping of fingers and vestigial organs in humans and other animals. Sydney Brenner, H. Robert Horvitz, and John E. Sulston received the Nobel Prize in Physiology or Medicine in 2002 for their work on the genetic regulation of organ development and programmed cell death. Research on cell lineages before and after embryonic development may lead to new ways to reduce or promote cell death, which can be important in preventing diseases such as Alzheimer's or cancer.

“Consensus on the Current Management of Endometriosis”, henceforth “Consensus”, was written by the World Endometriosis Society, or WES, president Neil P. Johnson and chief executive Lone Hummelshoj and published in 2013 in Human Reproduction. “Consensus” makes recommendations about managing endometriosis for women and healthcare professionals. Endometriosis is a condition where endometrium, the tissue that usually lines the uterus, grows outside of the uterus and is characterized by painful periods, heavy menstrual bleeding, and infertility. At a consortium held at the WES Montpellier on 8 September 2011 in Montpellier, France, participants from medical organizations and endometriosis support groups formed a consensus regarding the management of endometriosis. The “Consensus” serves as a set of evidence-based recommendations for healthcare professionals and women with endometriosis to guide treatment.

Walter Schiller studied the causes of diseases in the US and Austria in the early twentieth century and in 1928, invented the Schiller test, or a way to diagnose early cervical cancer in women. Cervical cancer is the uncontrollable division of cells in the cervix, or lower part of the uterus. While living in Austria until his emigration to escape the Nazis in 1937, Schiller concluded that there was a form of cervical cancer, later named carcinoma in situ, that physicians could detect earlier than when tumors start to appear. To determine whether women exhibited that early form of cancer, Schiller stained women’s cervixes with a type of iodine that would stain healthy cervical tissue and not cancerous cervical tissue. Cervical cancer is more deadly to women when it is caught later in its progression, and was difficult to detect in Schiller's time. Schiller’s research enabled physicians to diagnose cervical cancer early, helping women receive treatment quicker and ultimately helping to popularize annual diagnostic exams in the US.

In 1913, journalist Samuel Hopkins Adams published “What Can We Do About Cancer? The Most Vital and Insistent Question in the Medical World,” hereafter “What Can We Do About Cancer,” in Ladies’ Home Journal. Cancer is a disease that is the result of abnormal cell division in different parts of the body, such as the breasts or the cervix. During that time, many women did not discuss or disclose early symptoms of reproductive cancers, such as breast lumps and abnormal vaginal discharge, out of shame or disgust. Thus, people often considered cancer to be a taboo topic. “What Can We Do About Cancer?” provides a representation of what people in the early 1900s thought to be the early warning signs of cancer in women. Although, as of 2021, researchers have made advancements that have increased the scientific understanding of cancer and how it develops, Adams’ article provided women in the US during the 1900s with recommendations on early methods of cancer detection.