A decision by the Alabama Supreme Court that classifies frozen embryos as people has caused widespread concerns over the future of fertility treatments in the state, specifically in vitro fertilization.
The ruling has also led to a national conversation about IVF amid worries over the future legal status of the therapy.
Here are five things to know about IVF and its impact on reproductive health.
IVF is part of a larger menu of treatment options for infertility called Assisted Reproductive Technology, or ART, which also includes fertility medications, surrogacy or other procedures in which either eggs or embryos are handled outside of the body.
There are minimum standards of who can provide and perform IVF: a board-certified OB-GYN who has completed a three-year fellowship in reproductive endocrinology and infertility with appropriate nursing and other clinical personnel, in partnership with an board certified embryologist and laboratory director with a high-complexity laboratory capable of handling embryo cryopreservation and micromanipulation.
IVF consists of different stages. In the first stage, a patient's ovaries are stimulated with hormones so that an optimal number of eggs can be retrieved. Eggs are retrieved directly under ultrasound guided imaging.
The eggs are then fertilized with sperm from a partner or donor by placing each egg with a certain number of sperm cells, or by directly injecting the egg with sperm.
After fertilization, the embryo undergoes certain changes and divides at the "cleavage stage" (within three days) or the "blastocyst stage" (within five days). It can then be transferred to a person's uterus for implantation, in hopes of a successful pregnancy.
This is routinely done in multiple eggs simultaneously to achieve a higher rate of success.
Compared to blastocyst embryos, more cleavage stage embryos can be implanted at the same time because they have less of a chance of successfully implanting. With either method, multiple embryos are often implanted or selected from a larger group while the rest remain frozen.
Unused embryos can be frozen and stored indefinitely for future attempts, discarded, or used for research purposes wherein the embryo would be rendered nonviable.
The first baby to be born using IVF was a woman named Louise Brown, who was born in 1978 in England.
Three years later, in 1981, a baby was born in the United States using IVF.
The fertility treatment -- pioneered by British physiologist and Nobel Prize recipient Robert Edwards, obstetrician Dr. Patrick Steptoe, and embryologist and nurse Jean Purdy -- made it possible for otherwise infertile persons, who had no way to conceive a baby up until then, to become pregnant.
Today, IVF therapies contribute to approximately 1% to 3% of births worldwide, research shows.
In 1997, the U.S. Centers for Disease Control and Prevention began collecting data on the safety and success of IVF. In 2019, the agency launched the IVF success calculator, allowing families to estimate their chance at having a successful live birth using IVF.
Infertility is defined as the inability to achieve pregnancy within 12 months of unprotected sexual intercourse or therapeutic donor insemination for persons younger than 35 years, and within six months for women over the age of 35, according to the American College of Obstetricians and Gynecologists.
Infertility is a condition that affects as many as 15% of couples, according to the ACOG.
MORE: Physicians share concerns over IVF treatments pausing after Alabama court rulingIn evaluating patients for infertility, doctors consider everything from a detailed medical history of pregnancy, surgeries, menstrual history and other health conditions to other factors like a decreased number of eggs in the ovaries, physical blockages of the fallopian tubes or uterus, and male-partner factors, according to the ACOG.
IVF is a standard therapy for people seeking help for infertility.
The safety of IVF is comparable to any other medical procedure and people should discuss the process in full with their doctors.
Based on data collected by the CDC's ART data reports, in 2021, a total of 413,776 cycles of IVF were performed for patients, resulting in 112,008 pregnancies and 91,906 deliveries with 97,128 infants born. This translates to an average 82% overall success rate in terms of fertility.
MORE: Patients undergoing IVF in Alabama share fears after providers pause treatmentsMost patients who undergo IVF therapy are between 35 and 40 years of age, with the most success happening in younger-aged patients. Younger patients using their own eggs had better outcomes than patients using donor eggs overall, data shows.
The legality of infertility treatments like IVF has been a concern since 2022, when the U.S. Supreme Court overturned Roe v. Wade, giving states the power to decide whether or not abortion is legal.
A total of 16 states have ceased nearly all abortion services in the wake of the U.S. Supreme Court decision, including Alabama, where the procedure is banned in most circumstances.
With the recent Alabama Supreme Court "personhood" decision, clinicians and patients say they fear they may be vulnerable to prosecution based on their handling of frozen embryos used in the IVF process.
In its ruling, the court stated that "unborn children are 'children' … without exception based on developmental stage, physical location, or any other ancillary characteristics."
When the UAB Health System announced it would pause IVF procedures in the state, it shared concerns that its providers could be "prosecuted criminally" based on the court's ruling.
"We are saddened that this will impact our patients' attempt to have a baby through I.V.F.," it said in a Feb. 21 statement. "But we must evaluate the potential that our patients and our physicians could be prosecuted criminally or face punitive damages for following the standard of care for I.V.F. treatments."
Constantine Kanakis, M.D., MSc, a pathology and laboratory medicine resident physician at Loyola Medicine in Chicago, is a member of the ABC News Medical Unit.