In 2010, Maria Dominguez-Bello, Elizabeth Costello, Monica Contreras, and colleagues published “Delivery Mode Shapes the Acquisition and Structure of the Initial Microbiota Across Multiple Body Habitats in Newborns,” hereafter “Delivery Mode” in the journal Proceedings of the National Academy of Sciences. The term microbiota, which the authors use interchangeably with the term microbiome, refers to the collection of microorganisms, including bacteria, fungi, and viruses, found in and on the human body. The development of the microbiome, which begins at birth when a newborn is first exposed to the mother’s microbiota, impacts the development of the immune system, and how a person’s body responds to disease. Though researchers in the early 2000s were aware of a connection between delivery mode and the neonatal gut microbiome, they knew little about how delivery mode affects a neonate’s microbiome beyond the gut. Dominguez-Bello and associates’ experiment was one of the first to show that a neonate’s microbial community is uniform across their body and elaborate on the differences in microbiomes across delivery methods, which can make neonates born via c-section more susceptible to conditions such as asthma.

In 1961, Mary Lyon, a researcher who studied genetics, published “Gene Action in the X-chromosome of the Mouse (Mus Musculus L.),” hereafter “Gene Action in the X-chromosome,” in the journal Nature. Lyon’s paper focuses on the workings of female sex chromosomes, or X-chromosomes, and their implications for gene expression. A chromosome is a structure in a cell’s nucleus that contains the DNA, or genetic information, for each individual. In her paper, Lyon proposes her X-inactivation hypothesis, which states that one of the two X-chromosomes in mammalian female cells becomes inactive during early development, silencing its genetic activity. By describing X-chromosome inactivation, Lyon provided an explanation for the mosaic patterns observed in some female mammals, where different regions of their bodies exhibit distinct traits based on the genes carried by the particular X-chromosome that is active in that region. “Gene Action in the X-chromosome” provided evidence that X-chromosome inactivation occurs, laying the basis for understanding sex-linked traits, gene expression, and X-linked genetic diseases that impact thousands of people.

Maria Regina Torloni and colleagues published “Classifications for Cesarean Section: A Systematic Review,” hereafter “Classifications for C-sections,” in 2011 in the journal PLOS One. A Cesarean section, or C-section, is a surgical birth through an incision in the pregnant person’s abdomen and uterus. Across the world, medical professionals use many different C-section classification systems to group the procedures according to particular features of the medical situation, such as the person undergoing the C-section or their specific medical needs. The authors of “Classifications for C-sections” systematically review the various available classification systems and evaluate them to identify their strengths and weaknesses. In “Classifications for C-sections,” the authors stress the need for a standardized classification system that experts can use to communicate internationally and address the health needs of pregnant people seeking C-sections.

In 2020, Osamah Batiha and colleagues published their article “Impact of COVID-19 and Other Viruses on Reproductive Health,'' hereafter “Impact of COVID-19,” in the journal Andrologia. The article is a literature review that encompasses various studies on how coronavirus disease 2019, or COVID-19, impacts male fertility and pregnancy. COVID-19 is a viral disease that primarily infects the respiratory system and causes infection through the virus severe acute respiratory syndrome coronavirus 2, or SARS-CoV-2. The researchers published “Impact of COVID-19” during the middle of the COVID-19 pandemic, which was a time of global panic and uncertainty. “Impact of COVID-19” was one of the first studies to examine the potential effects of COVID-19 on male fertility and elicited discussion within the scientific community regarding the necessary safety precautions to take during viral pandemics.

In 1997, Herbert B. Peterson and colleagues published “The Risk of Ectopic Pregnancy after Tubal Sterilization,” hereafter “The Risk of Ectopic Pregnancy,” in The New England Journal of Medicine. The article contains the authors’ reports on the United States Collaborative Review of Sterilization, a multi-hospital study the authors performed from 1978 through 1994 that involved over 10,000 patients from across the United States undergoing tubal sterilization, a common method of permanent contraception for people with female reproductive systems. “The Risk of Ectopic Pregnancy” reveals that bipolar coagulation, one of the methods of tubal sterilization, is associated with a higher risk of an ectopic pregnancy, a life-threatening pregnancy complication, after sterilization. “The Risk of Ectopic Pregnancy” was an early study into the possible complications from tubal sterilization, and its authors reveal the risk of a serious health consequence associated with a popular method of contraception.

In September 2018, the American College of Obstetricians and Gynecologists, or ACOG, published “Labor and Delivery Management of Women with Human Immunodeficiency Virus Infection,” hereafter “Labor and Delivery Management.” It appeared as ACOG Committee Opinion Number 751 in the journal Obstetrics & Gynecology. The article contains recommendations for physicians who care for pregnant people with human immunodeficiency virus, or HIV, to reduce the risk of transmission of the virus from parent to child. Those recommendations include treating pregnant people with HIV therapies, consistently testing and monitoring the levels of HIV in a pregnant person’s blood, and scheduling a cesarean section, or C-section, rather than a vaginal birth to reduce transmission risk in some cases. “Labor and Delivery Management” provides recommendations for physicians to decrease the risk of mother-to-child transmission and emphasizes that physicians and pregnant people make decisions regarding labor and delivery together.

In 2020, Rebecca Flyckt and colleagues published “First Birth from a Deceased Donor Uterus in the United States: From Severe Graft Rejection to Successful Cesarean Delivery,” hereafter “First Birth from a Deceased Donor,” in the American Journal of Obstetrics and Gynecology. In the article, Flyckt and colleagues explain that they performed one of the first uterus transplantations with a uterus from a deceased donor in the United States and detail how they did so successfully. All deceased donors in the study were considered brain-dead, not cardiac-dead. Uterus transplantation from a deceased donor is a surgical procedure in which a researcher transplants a healthy uterus from a brain-dead, deceased donor into a recipient with a diseased or absent uterus. Prior to 2020, researchers performed several uterus transplantations with live donors that resulted in live births, but there was only one recorded live birth from a deceased uterus donor. Flyckt and colleagues provide summary data about uterus transplantations from deceased donors and compare the efficacy of transplantations from live donors to those from deceased donors. “First Birth from a Deceased Donor” advances the techniques that can make uterus transplants from deceased donors successful, which allows people with uterine disorders the opportunity to become pregnant and have children.

In April 2017, Alan Flake and colleagues published “An Extra-Uterine System to Physiologically Support the Extreme Premature Lamb,” hereafter “An Extra-Uterine System,” in the journal Nature Communications. “An Extra-Uterine System” reports on the development and testing of an artificial uterus system to keep alive prematurely born animals. Prematurity, or birth prior to thirty-seven weeks of gestational development, is the global leading cause of death in children under the age of five years. The artificial uterus technology, which the authors call the Biobag, is a flexible, sealable container. It’s filled with fluid and nutrients, which replicate the environment of a uterus, the organ where a fetus typically develops. Flake and colleagues showed that their Biobag technology could keep eight premature fetal lambs alive for up to four weeks. “An Extra-Uterine System” provoked discussion among scientists and the public about the possible use of the technology to improve survival rates for premature infants and the ethics of possible future uses of the technology.

In 2015, Mats Brännström and colleagues published “Livebirth after Uterus Transplantation” in the journal The Lancet. In “Livebirth after Uterus Transplantation,” Brännström and colleagues explain that they conducted one of the first uterus transplantations that resulted in a live birth, and they detail how they did so successfully. Uterus transplantations are a surgical procedure in which surgeons transplant a uterus from an eligible donor into a recipient with uterine infertility disorders, or UFIs, such as an absent or diseased uterus. Women with UFIs can neither conceive nor carry a pregnancy to term naturally, so uterus transplantations remain one of the only treatments available that offer them the possibility to become pregnant as of 2025. Prior to 2013, researchers worldwide had performed human uterus transplantations, but the procedures had not resulted in any reported live births. “Livebirth after Uterus Transplantation” shows that uterus transplantations can allow women with uterine infertility, which affects one in 500 women of reproductive age, the opportunity to experience pregnancy.

In 2019, US-based pediatric heart doctor Clayton Smith and colleagues published “Long-Term Outcomes of Tetralogy of Fallot: A Study From the Pediatric Cardiac Care Consortium,” hereafter, “Long-Term Outcomes,” in JAMA Cardiology. The Tetralogy of Fallot, or TOF, is a group of four congenital anatomical heart abnormalities, all of which lead to the circulation of oxygen-poor blood throughout the body. Congenital conditions are ones that are present from birth. The researchers, who at the time of publication were all affiliated with US medical schools or hospitals, investigated the long-term outcomes of individuals who underwent several different types of complete repair surgery, which is the surgery that remedies all four TOF defects, within the first three months of life. Prior to the release of “Long-Term Outcomes,” studies of TOF outcomes used data from single centers in the US or non-US patient cohorts. “Long-Term Outcomes” was one of the largest US-based, multicenter studies to evaluate the effectiveness of different strategies of complete surgical repair in remedying TOF, a condition that affects around 1,700 infants born in the US every year.