In their 2014 article “A Comparison of the Menstruation and Education Experiences of Girls in Tanzania, Ghana, Cambodia, and Ethiopia,” hereafter “Comparison of Menstruation,” researchers Marni Sommer, T. Mokoah Nana Ackatia-Armah, Susan Connolly, and Dana Smiles examined various physical and social barriers impacting women’s management of menstrual health across Ghana, Cambodia, and Ethiopia. The authors examined barriers such as misinformation about menstruation and how schools limit girls’ ability to manage their menstrual cycles. They then compared their findings to a previous study led by Sommer on similar experiences shared by girls living in Tanzania. “Comparison of Menstruation” provides insight into the physical and social barriers to managing menstruation in low-resource contexts and serves as a precursor to the creation of educational resources intended to improve menstruation health management for women and girls.

On 5 April 2018, the documentary Period. End of Sentence. premiered at the Cleveland International Film Festival in Cleveland, Ohio. In the documentary, Rayka Zehtabchi, the director of the film, documents the stigma surrounding menstruation in India and follows a group of women in Kathikhera, a rural village in the Hapur district of India, as they manufacture and distribute sanitary pads. A group of high school students at Oakwood High School in Los Angeles, California, raised money to produce the documentary after one student was inspired by her visit to the United Nations Commission on the Status of Women in New York City, New York, which focused on the stigma surrounding menstruation in low-income countries. Period. End of Sentence. draws attention to the obstacles impeding proper menstrual health management in low-income contexts by documenting the women of Kathikhera’s journey to manufacture and sell sanitary pads.

In 2010, Sophia and Paul Grinvalds founded the organization AFRIpads in Kampala, Uganda, to provide reusable cloth pads to menstruating women and girls throughout the country. At that time, the Grinvalds wanted to help implement better menstrual health and hygiene in Uganda to encourage women and girls to engage in work and school. While living in Kampala, in 2010, they employed Ugandan women to sew cloth pads daily and sell to others living in the local village. In 2018, the United Nations Human Rights Council, or UNHRC, conducted a study in Uganda to test the efficiency of AFRIpads and found that a majority of women and girls studied favored reusable cloth pads. Since then, as of 2021, AFRIpads has expanded to collaborate with other organizations to distribute their reusable cloth pads to women and girls living in African countries. By doing so, AFRIpads has helped introduce a sustainable method for managing menstrual hygiene and teaching menstrual education in low-income countries.

Telomeres are sequences of DNA on the ends of chromosomes that protect chromosomes from sticking to each other or tangling, which could cause irregularities in normal DNA functions. As cells replicate, telomeres shorten at the end of chromosomes, which correlates to senescence or cellular aging. Integral to this process is telomerase, which is an enzyme that repairs telomeres and is present in various cells in the human body, especially during human growth and development. Telomeres and telomerase are required for normal human embryonic development because they protect DNA as it completes multiple rounds of replication.

The Y-chromosome is one of a pair of chromosomes that determine the genetic sex of individuals in mammals, some insects, and some plants. In the nineteenth and twentieth centuries, the development of new microscopic and molecular techniques, including DNA sequencing, enabled scientists to confirm the hypothesis that chromosomes determine the sex of developing organisms. In an adult organism, the genes on the Y-chromosome help produce the male gamete, the sperm cell. Beginning in the 1980s, many studies of human populations used the Y-chromosome gene sequences to trace paternal lineages. In mammals, the Y-chromosomes contain the master-switch gene for sex determination, called the sex-determining region Y, or the SRY gene in humans. In most normal cases, if a fertilized egg cell, called a zygote, has the SRY gene, the zygote develops into an embryos that has male sex traits. If the zygote lacks the SRY gene or if the SRY gene is defective, the zygote develops into an embryo that has female sex traits.

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.

Barbara McClintock conducted experiments on corn (Zea mays) in the United States in the mid-twentieth century to study the structure and function of the chromosomes in the cells. McClintock researched how genes combined in corn and proposed mechanisms for how those interactions are regulated. McClintock received the Nobel Prize in Physiology or Medicine in 1983, the first woman to win the prize without sharing it. McClintock won the award for her introduction of the concept of transposons, also called jumping genes. McClintock conceptualized some genetic material as not static in structure and order, but as subject to re-arrangement and may be altered during development.

Curt Jacob Stern studied radiation and chromosomes in humans and fruit flies in the United States during the twentieth century. He researched the mechanisms of inheritance and of mitosis, or the process in which the chromosomes in the nucleus of a single cell, called the parent cell, split into identical sets and yield two cells, called daughter cells. Stern worked on the Drosophila melanogaster fruit fly, and he provided early evidence that chromosomes exchange genetic material during cellular reproduction. During World War II, he provided evidence for the harmful effects of radiation on developing organisms. That research showed that mutations can cause problems in developing fetuses and can lead to cancer. He helped explain how genetic material transmits from parent to progeny, and how it functions in developing organisms.

Estrogen is the primary sex hormone in women and it functions during the reproductive menstrual cycle. Women have three major types of estrogen: estrone, estradiol, and estriol, which bind to and activate receptors within the body. Researchers discovered the three types of estrogen over a period of seven years, contributing to more detailed descriptions of the menstrual cycle. Each type of estrogen molecule contains a slightly different arrangement or number of atoms that in turn causes some of the estrogens to be more active than others. The different types of estrogen peak and wane throughout women's reproductive cycles, from normal menstruation to pregnancy to the cessation of menstruation (menopause). As scientists better explained the effects of estrogens, they used that information to develop oral contraceptives to control pregnancy, to map the menstrual cycle, and to create hormone therapies to regulate abnormal levels of estrogen.

Kurt Benirschke studied cells, placentas, and endangered species in Germany and the US during the twentieth century. Benirschke was professor at the University of California in San Diego, California, and a director of the research department at the San Diego Zoo in San Diego, California. He also helped form the research department of the San Diego Zoo and its sister organization, the Center for Reproduction of Endangered Species. Benirschke contributed to the field of embryology through his work on human and animal reproduction, including work on human placentas and birth defects, through work on the structure of chromosomes, and through work on the reproduction and conservation of endangered species.