At what point does human life begin? For decades, science has had a clear answer: fertilization.
Below we recall 5 instances where science indicated that human life begins at conception.
1. Book of Medical Embryology by Jan Langman
In 1975, the third edition of Jan Langman’s famous book Medical Embryology explained that “human development begins with fertilization, a process by which two highly specialized cells, the male sperm and the female egg, join together to form a new organism , the zygote ”.
The most recent edition of the book states that “development begins with fertilization.”
2. Fundamentals of Human Embryology, by Keith Moore
Keith Moore’s book Essentials of Human Embryology (published in 1988) agrees that “human development begins after the union of male and female gametes or germ cells in a process known as fertilization (conception)”.
The fertilized egg, “known as a zygote,” says the book, “is a large diploid cell that is the beginning, or original, of man.
3. A study published by Nature
“The mammalian life cycle begins when a sperm enters an egg,” said a study published in 2010 in the journal Nature by Yukinori Okada and other scientists, titled “A Role for the Elongator Complex in Demethylation of the Zygotic Paternal Genome” .
4. A new survey in 2012
Research conducted by Janetti Signorelli and other scientists in 2012 concluded that “fertilization is the process by which the haploid male and female gametes (sperm and egg) unite to produce a genetically distinct individual.”
5. “Humans in development”, by Moore, TVN Persaud and Mark Torchia
In 2015, scientists Keith Moore, TVN Persaud and Mark Torchia stated in the latest edition of their book The Developing Human: Clinically Oriented Embryology that “human development is a continuous process that begins when a female’s egg is fertilized by a sperm. of a male ”.
“Human development begins at fertilization when a sperm fuses with an egg to form a single cell, the zygote,” they wrote.
The scientists further noted that “all major external and internal structures are formed between weeks 4 and 8,” and “the upper limb outbreaks are recognizable on day 26 or 27 as small swellings on the walls of the ventrolateral body.”
Towards the end of the eighth week, they noted, “the embryo has distinct human characteristics; however, the head is still disproportionately large and makes up almost half of the embryo ”.