Statutes in 30 states specifically define the terms fertilization, conception, or both. Statutes in 16 states explicitly define conception at fertilization. No state statutes define conception at a point other than fertilization.
Alabama
Fertilization. — The fusion of a human spermatozoon with a human ovum.
Conception. — The fusion of a human spermatozoon with a human ovum.
Citation: Code of Ala. §§ 26-22-2(2), 26-23B-3(3), 26-23A-3(2)
Alaska
“[F]ertilization” means the fusion of a human spermatozoon with a human ovum[.]
Citation: Alaska Stat. § 18.05.032(c)(2)
Arizona
“Conception” means the fusion of a human spermatozoon with a human ovum.
Citation: Ariz. Rev. Stat. § 36-2151(4)
Arkansas
“Fertilization” means the fusion of a human spermatozoon with a human ovum[.]
Citation: Ark. Code Ann. §§ 5-61-403(2), 20-16-1402(3)
California
As used in this section “conceived” means the fertilization of a human ovum by a human sperm.
Citation: Cal Civ Code § 43.6(c)
District of Columbia
“Fertilization” means a multi-step process that results in the formation of a zygote by the union of a sperm and an egg.
Citation: D.C. Code § 16-401(11)
Florida
“Fertilization” means the initial union of an egg and sperm.
Citation: Fla. Stat. Ann. § 742.13(4)
Idaho
“Fertilization” means the fusion of a human spermatozoon with a human ovum[.]
Citation: Idaho Code § 18-502(3)
Indiana
“Fertilization”, for purposes of IC 16-34, means the fusion of a human spermatozoon with a human ovum.
Citation: Ind. Code Ann. § 16-18-2-128.3
Iowa
“Fertilization” means the fusion of a human spermatozoon with a human ovum.
Citation: Iowa Code § 146B.1(4)
Kansas
“Fertilization” means the fusion of a human spermatozoon with a human ovum.
Citation: Kan. Stat. Ann. §§ 65-6701(e), 65-6732(c)(1)
Kentucky
“Fertilization” means the fusion of a human spermatozoon with a human ovum[.]
“Fertilization” means that point in time when a male human sperm penetrates the zona pellucida of a female human ovum[.]
“Conception” means fertilization[.]
Citation: Ky. Rev. Stat. §§ 311.781(1), 311.772(1)(a), 311.7701(1)
See also: KRS § New[Added by 2017 Ky. SB 5](1), Ky. Rev. Stat. § 311.7701(3)
Louisiana
“Conception” or “fertilization” means the fusion of a human spermatozoon with a human ovum.
“Fertilization” means the fusion of a human spermatozoon with a human ovum.
“Fertilization” means that point in time when a male human sperm penetrates the zona pellucida of a female human ovum.
Citation: La. Rev. Stat. Ann. §§ 14:87.1(5) and (9), 40:1061(I)(1)
Massachusetts
“Fertilization”, the process whereby the male and female gametes unite to form an embryo.
Citation: Mass. Ann. Laws ch. 111L, § 2
Mississippi
“Conception” means the fusion of human spermatozoon with a human ovum.
Citation: Miss. Code Ann. § 41-41-405(f), 41-41-191(3)(c)
Missouri
“Conception”, the fertilization of the ovum of a female by a sperm of a male[.]
Citation: Mo. Rev. Stat. § 188.015(3)
See also: Mo. Rev. Stat. § 196.1127(2)(3)
Montana
“Fertilization” means the fusion of a human spermatozoon with a human ovum.
Citation: Mont. Code Ann. § 50-20-602(1)
Nebraska
Fertilization means the fusion of a human spermatozoon with a human ovum[.]
Conception means the fecundation of the ovum by the spermatozoa[.]
Citation: Neb. Rev. Stat. Ann §§ 28-3103(3), 28-326(3)
New Hampshire
“Conception” means the fusion of a human spermatozoon with a human ovum.
Citation: N.H. Rev. Stat. Ann. § 329:43(III)
New Jersey
“Fertilization” means the initial union of the sperm and the egg.
Citation: N.J. Stat. § 9:17-62
New Mexico
“[C]onception” means the fertilization of the ovum of a human female by the sperm of a human male[.]
Citation: N.M. Stat. Ann. § 24-9A-1
North Dakota
“Fertilization” means the fusion of a human spermatozoon with a human ovum.
Citation: N.D. Cent. Code § 14-02.1-02(6)
Ohio
“Fertilization” means the fusion of a human spermatozoon with a human ovum.
“Conception” means fertilization.
Citation: Ohio Rev. Code Ann. § 2919.16(A), 2919.20(A), 2919.19(A)(1)
Oklahoma
“Fertilization” means the fusion of a human spermatozoon with a human ovum[.]
“Conception” means the fertilization of the ovum of a female individual by the sperm of a male individual[.]
Citation: Okla. Stat. tit. 63, §§ 1-745.2(4), 1-745.31(2), 1-730(A)(7)
Pennsylvania
“Fertilization” and “conception.” —Each term shall mean the fusion of a human spermatozoon with a human ovum.
Conception. — A person shall be deemed to be conceived at the moment of fertilization.
Citation: 18 Pa. Cons. Stat. Ann. § 3203; 42 Pa. Cons. Stat. Ann. § 8305(c)
South Carolina
“Conception” means the fecundation of the ovum by the spermatozoa.
“Fertilization” means the fusion of a human spermatozoon with a human ovum.
“Conception” means fertilization.
Citation: S.C. Code Ann. §§ 44-41-10, 44-41-430(4), 44-41-610(1)
South Dakota
The term “conception,” as used in this section, means the fertilization of a human ovum by a human sperm, which occurs when the sperm has penetrated the cell membrane of the ovum.
“Fertilization,” that point in time when a male human sperm penetrates the zona pellucida of a female human ovum[.]
Citation: S.D. Codified Laws §§ 21-55-1, 34-23A-1(3)
Tennessee
“Fertilization” means that point in time when a male human sperm penetrates the zona pellucida of a female human ovum[.]
For the purposes of this section, a person is deemed to be conceived at the moment of fertilization, as that term is defined in § 39-15-213.
Citation: Tenn. Code Ann. §§ 39-15-213(a)(2), 29-34-212(c)
Texas
“Fertilization” means the point in time when a male human sperm penetrates the zona pellucida of a female human ovum.
Citation: Tex. Health & Safety Code § 170A.001(2)
West Virginia
“Fertilization” means the fusion of a human spermatozoon with a human ovum.
Citation: W. Va. Code §§ 16-2M-2(3), 16-2R-2