The term fetal rights came into wide usage after Roe v. Wade, the 1973 landmark case that legalized abortion in the United States and was essentially overturned in 2022.
[7] The term fetus itself is not exactly suitable for legal purposes, as it denotes only a part of the prenatal period with a starting point that remains unclear.
[15] Roman jurist Ulpian noted that "in the Law of the Twelve Tables he who was in the womb is admitted to the legitimate succession, if he has been born".
[16] Another jurist Julius Paulus similarly noted, that "the ancients provided for the free unborn child in such a way that they preserved for it all legal rights intact until the time of birth".
In 1284, King of Scotland Alexander III designated his future unborn children as heirs presumptive by the act of parliament to avoid potential squabbles among loyal descendants of his lineage.
[25] After the death of Albert II of Germany in 1439, his then-unborn son Ladislaus the Posthumous inherited his father's sovereign rights.
[26] In 1536, the British Parliament gave the unborn children of Henry VIII and Jane Seymour precedence in the line of royal succession.
[29] In 1762, English jurist and judge William Blackstone wrote that an "infant in its mother's womb" could benefit from a legacy and receive an estate as if it were actually bom.
[30] Similarly to the Roman law, the Napoleonic Code envisaged that if a woman becomes a widow, a male guardian should be appointed for her unborn child.
In 1948, the Declaration of Geneva was adopted which prior to amendments in 1983 and 2005, advised physicians to "maintain the utmost respect for human life from the time of its conception".
[35] In 1983, Ireland was one of the first countries in the world to constitutionalize a fetal right to life by passing the Eighth Amendment to the Constitution, later repealed in September 2018.
Mexico ratified the convention with the reservation that the expression "in general" concerning the fetal right to life does not constitute an obligation and that this matter falls within the domain of the states.
[40] While the convention may be interpreted to permit domestic abortion laws in exceptional circumstances, it effectively declares the fetus a person.
[40] However, only a minority of state ratifiers completely prohibit abortion without allowing for an exception when the pregnant woman's life is in danger (Dominican Republic, El Salvador and Nicaragua).
[51] Two European Union member states (Hungary and Slovakia) grant the fetus the constitutional right to life.
[55] The twenty-three weeks is usually regarded as the lower bound of fetal viability because technology has been unable to surpass the limit set by lung development.
According to Aude Bertrand-Mirkovic, children in the prenatal stage are human persons but do not need legal personhood, as their rights can be protected by objective law.
[87] On 25 May 2018, a referendum was passed[88] which amended the Constitution by the substitution of the former provision recognising the right to life of the unborn, with one permitting the Oireachtas, the Irish Parliament, to legislate for the termination of pregnancies.
[93] The civil codes of several countries, such as China (including Hong Kong and Macau)[94] and Russia, as well as some US states,[91] grant fetus inheritance rights, usually under the born alive rule.
[95] The civil codes of the Philippines and Spain envisage that donations to the unborn children can be made and accepted by "persons who would legally represent them if they were already born".
[98] Alongside Norway, the Constitution of Bhutan grants the unborn royal children the right to succession, but only if there is no male heir.
[99] Various initiatives, prompted by concern for the ill effects which might be posed to the health or development of a fetus, seek to restrict or discourage women from engaging in certain behaviors while pregnant.