Embryo Project Encyclopedia

In 2001, the Supreme Court of New Jersey decided a dispute between a divorced couple over cryopreserved preembryos created through in vitro fertilization (IVF) during the coupleÕs marriage. The former wife (J.B.) wanted the preembryos destroyed, while her former husband (M.B.) wanted them to be used for future implantation attempts, such as by an infertile couple. In J.B. v. M.B. (2001), the court declined to force J.B. to become a parent against her will, concluding that doing so would violate state public policy. Instead, the Supreme Court of New Jersey decided that agreements directing the allocation of cryopreserved preembryos will be enforced, unless one party changes his or her mind prior to the preembryosÕ use or destruction. Should a party revoke an earlier decision about the preembryos, New Jersey courts should weigh the partiesÕ interests with special weight given to an individualÕs right to not procreate.

Ovism was one of two models of preformationism, a theory of generation prevalent in the late seventeenth through the end of the eighteenth century. Contrary to the competing theory of epigenesis (gradual emergence of form), preformationism held that the unborn offspring existed fully formed in the eggs or sperm of its parents prior to conception. The ovist model held that the maternal egg was the location of this preformed embryo, while the other preformationism model known as spermism preferred the paternal germ cell, as the name implies.

This embryology image is a pencil sketch by Nicolaas Hartsoeker, published as part of his 1694 French-language paper entitled Essai de Dioptrique, a semi-speculative work describing the sorts of new scientific observations that could be done using magnifying lenses. Dioptrique was published in Paris by the publishing house of Jean Anisson. The image depicts a curled up infant-like human, now referred to as a homunculus, inside the head of a sperm cell. This sketch is important to embryology because it is one of the most illustrative examples of preformationism, a theory of generation stating that each future member of any given species exists, fully formed though miniscule, within the gametic cells (sperm or eggs) of its parents. This theory was popular among naturalists in the eighteenth century.

Nicolaas Hartsoeker, a Dutch astronomer, optics manufacturer, and naturalist, was born 26 March 1656 in Gouda, Netherlands, and died 10 December 1725. His mother was Anna van der Mey and his father was Christiaan Hartsoeker, a prominent evangelical minister. His major contribution to embryology was his observations of human sperm cells, which he claimed to be the first to see under a microscope. His sketch of the homunculus, a tiny preformed human he believed to exist in the head of spermatazoa, is his lasting scientific legacy in the field of embryology. This sketch was only a minor part of his first publication, Essai de Dioptrique (1694), which dealt primarily with the use of optical lenses in science. In subsequent years the sketch became iconic of the theory of embryological development known now as preformationism. Hartsoeker himself was a vocal adherent of spermist preformationism and is often cited as the originator of the idea.

Preformationism was a theory of embryological development used in the late seventeenth through the late eighteenth centuries. This theory held that the generation of offspring occurs as a result of an unfolding and growth of preformed parts. There were two competing models of preformationism: the ovism model, in which the location of these preformed parts prior to gestation was the maternal egg, and the spermism model, in which a preformed individual or homunculus was thought to exist in the head of each sperm. Preformationism was a widely-held theory by Enlightenment-era scientists, but by the early 1800s, most scientists had abandoned it, in part because higher magnification in microscopes enabled them to see the very earliest stages of embryos as small collections of cells. Prior to preformationism, naturalists who studied embryo development favored the theory of spontaneous generation in lower animals, such as flies, which appeared to arise from manure. In higher animals, however, scientists used the theory of epigenesis put forth by Aristotle, who said that maternal and paternal fluids came together in the uterus and solidified during early gestation into a fetus. Preformationism was the first theory of generation and development that applied to all organisms in the plant and animal kingdoms.

In Jeter v. Mayo, the Court of Appeals of Arizona in 2005 held that a cryopreserved, three-day-old pre-embryo is not a person for purposes of Arizona's wrongful death statutes, and that the Arizona Legislature was best suited to decide whether to expand the law to include cryopreserved pre-embryos. The Court of Appeals affirmed a decision by the Maricopa County Superior Court to dismiss a couple's wrongful death claim after the Mayo Clinic (Mayo) allegedly lost or destroyed several of their cryopreserved pre-embryos. In reaching its decision, the Court of Appeals explored ethical and legal issues relating to cryopreserved pre-embryos, including prior case law, the principles of statutory construction, and the Arizona Legislature's role in balancing the societal interests involved.

In Maureen Kass v. Steven Kass (1998), the Court of Appeals of New York in Albany, New York, ruled that the state should generally consider IVF consent forms signed by participants in an in vitro fertilization (IVF) program valid, binding, and enforceable in the event of a dispute. The court indicated that decisions regarding the handling of cryopreserved pre-zygotes, often called preembryos, contained within these consent forms should be upheld. Although Steven and Maureen Kass had signed IVF consent forms agreeing to donate unused preembryos to research, during their divorce Maureen argued for custody of the preembryos. The New York Court of Appeals ruled in favor of Steven Kass and concluded that the informed consent forms signed by the former couple had clearly manifested the coupleÕs mutual intent to donate any preembryos to research in the event of a dispute.

Marcello Malpighi studied chick embryos with microscopes in Italy during the seventeenth century. Trained as a medical doctor, he was among the first scientists to use the microscope to examine embryos at very early stages. Malpighi described early structures in chick embryos, and later scientists used his descriptions to help develop the theory of preformationism.

In A.Z. v. B.Z. (2000), the Supreme Judicial Court of Massachusetts in Boston, Massachusetts, affirmed a lower courtÕs decision, ruling that contracts that require a party to become a parent against his or her will are unenforceable and contrary to public policy. The case centered around A.Z. and B.Z., a divorced couple who had previously used in vitro fertilization (IVF) to start a family together during their marriage and had several preembryos cryopreserved as part of the process. While undertaking IVF, the couple signed multiple consent forms requiring them to decide what should happen to the cryopreserved preembryos in the event of certain listed contingencies, such as death or separation of the couple. The couple indicated their preference that B.Z., A.Z.Õs now former wife, could use the cryopreserved preembryos if the couple later separated. When their relationship deteriorated, however, A.Z. objected to B.Z.Õs attempt to have additional children using the preembryos, leading to a lengthy legal battle. The court case A.Z. v. B.Z. established Massachusetts public policy that people should not be forced to become a parent against their will, even if they previously agreed to provide their genetic material for reproduction.

From its founding in 1910 until it closed its doors in 1939, the Eugenics Record Office (ERO) at Cold Spring Harbor Laboratory in New York was the center of the American Eugenics Movement. Charles Davenport, a geneticist and biologist, founded the ERO, and served as its director until 1934. Under the direction of Davenport and his associate, superintendant Harry H. Laughlin, the influence of the ERO on science and public policy waxed during the early twentieth century until after World War II. The ERO is important to the history of embryology because of the key role it played in the application of scientific theories about heredity to the formulation of reproductive social policies.