Actually, thanks to advancements in science we DO know that a new human being is formed and created and begins its life at conception.
“The life cycle of mammals begins when a sperm enters an egg.” Okada et al., A role for the elongator complex in zygotic paternal genome demethylation, NATURE 463:554 (Jan. 28, 2010)
“Fertilization is the process by which male and female haploid gametes (sperm and egg) unite to produce a genetically distinct individual.”Signorelli et al., Kinases, phosphatases and proteases during sperm capacitation, CELL TISSUE RES. 349(3):765 (Mar. 20, 2012)
“Fertilization – the fusion of gametes to produce a new organism – is the culmination of a multitude of intricately regulated cellular processes.” Marcello et al., Fertilization, ADV. EXP. BIOL. 757:321 (2013)
“Human life begins at fertilization, the process during which a male gamete or sperm (spermatozoo developmentn) unites with a female gamete or oocyte (ovum) to form a single cell called a zygote. This highly specialized, totipotent cell marked the beginning of each of us as a unique individual.” “A zygote is the beginning of a new human being (i.e., an embryo).” Keith L. Moore, The Developing Human: Clinically Oriented Embryology, 7th edition. Philadelphia, PA: Saunders, 2003. pp. 16, 2.
“In that fraction of a second when the chromosomes form pairs, the sex of the new child will be determined, hereditary characteristics received from each parent will be set, and a new life will have begun.” Kaluger, G., and Kaluger, M., Human Development: The Span of Life, page 28-29, The C.V. Mosby Co., St. Louis, 1974
An embryology textbook describes how birth is just an event in the development of a baby, not the beginning of his/her life:
“It should always be remembered that many organs are still not completely developed by full-term and birth should be regarded only as an incident in the whole developmental process.” F Beck Human Embryology, Blackwell Scientific Publications, 1985 page vi
“It is the penetration of the ovum by a sperm and the resulting mingling of nuclear material each brings to the union that constitutes the initiation of the life of a new individual.” Clark Edward and Corliss Patten’s Human Embryology, McGraw – Hill Inc., 30
“Although it is customary to divide human development into prenatal and postnatal periods, it is important to realize that birth is merely a dramatic event during development resulting in a change in environment.” The Developing Human: Clinically Oriented Embryology fifth edition, Moore and Persaud, 1993, Saunders Company, page 1
“The zygote and early embryo are living human organisms.” Keith L. Moore & T.V.N. Persaud Before We Are Born – Essentials of Embryology and Birth Defects (W.B. Saunders Company, 1998. Fifth edition.) Page 500
“Thus a new cell is formed from the union of a male and a female gamete. [sperm and egg cells] The cell, referred to as the zygote, contains a new combination of genetic material, resulting in an individual different from either parent and from anyone else in the world.” Sally B Olds, et al., Obstetric Nursing (Menlo Park, California: Addison – Wesley publishing, 1980) P 136
“The term conception refers to the union of the male and female pronuclear elements of procreation from which a new living being develops. It is synonymous with the terms fecundation, impregnation, and fertilization … The zygote thus formed represents the beginning of a new life.” J.P. Greenhill and E.A. Freidman. Biological Principles and Modern Practice of Obstetrics. Philadelphia: W.B. Saunders Publishers. 1974 Pages 17 and 23.
“[All] organisms, however large and complex they might be as full grown, begin life as a single cell. This is true for the human being, for instance, who begins life as a fertilized ovum.”Dr. Morris Krieger “The Human Reproductive System” p 88 (1969) Sterling Pub. Co