Some of the most powerful pieces of information regarding abortion we can share are the details of the development of human life in the womb.
In this section, use of the word “baby” has been avoided, because this word presupposes the very thing we’re trying to show — the humanity of the unborn — and we don’t want anyone to tune out the information we’re trying to share.
Of course, there may be times when you’re talking to someone who will respond positively to hearing about “the baby’s heartbeat”; in such a case, you should feel free to modify your language.
Please note that embryonic and fetal development is presented here by referring to days or weeks after conception, which may be different from the less precise “weeks of pregnancy” typically used by obstetricians, which are calculated from the mother’s last menstrual period (LMP).
When does life begin?
Biology is clear that at conception, also known as fertilization, a unique organism comes into existence. Since this new life possesses human DNA and is the offspring of human parents, it can only legitimately be described as human life.
Since there is no question that human zygotes, embryos and fetuses are alive, some have attempted to claim that human beings are not “persons” until some threshold is crossed, such as viability, the capacity to feel pain, birth, or even the first year after birth. The merits of such notions could be debated, but it should be clear that they are not based on science but rather on ideology, philosophy, or belief.
As far as observable science is concerned, human life begins at conception.
Source: Condic, Maureen, MD. When Does Human Life Begin? A Scientific Perspective. The Westchester Institute for Ethics and the Human Person. http://www.westchesterinstitute.net/images/wi_whitepaper_life_print.pdf.
What happens at conception?
What is the difference between “fertilization” and “implantation?”
Fertilization, also known as conception, is described above, and occurs in the mother’s Fallopian tube. Implantation, which occurs 8 to 10 days after fertilization, refers to the point at which the new human being (now scientifically referred to as an “embryo”) implants in the mother’s uterus and begins to draw nourishment.
Source: Willke, John, MD and Barbara Willke. 2003. Abortion: Questions & Answers. Cincinnati: Hayes Publishing Company.
What are the various stages of development in the womb?
- Zygote—A single-celled human being from fertilization until the first cell division
- Embryo—A human being from the time of the first cell division until approximately the eighth week of life
- Fetus—A human being from approximately the eighth week of life up until birth
- First Trimester—From conception to approximately 12 weeks gestation
- Second Trimester—From approximately 13 through 26 weeks gestation
- Third Trimester—From approximately 27 weeks gestation to birth
When does an Embryo’s Heart Begin to Beat?
When can an embryo’s brain waves be detected?
When do a Fetus’ Fingernails Begin to Form?
When can a Fetus Feel Pain?
What are Some of the Other Milestones of Fetal Development?
- At nine weeks after conception, a fetus is able to bend its fingers around an object in its hand, and sucks its thumb.
- At 11 weeks, a fetus is breathing amniotic fluid steadily and will do so until birth.
- At 12 weeks, a fetus can kick, turn over, make a fist, open its mouth and press its lips together.
- At 13 weeks, a fetus’ sense are present.
- At 20 weeks, a fetus can be startled by a loud external noise.
- At 23 weeks, a fetus can demonstrate rapid eye movements (REM).
- At six months, fine hair grows on the fetus’ head and eyebrows, and small eyelashes begin to appear.
- At seven months, a fetus’ hands can support his entire weight.
- At eight months, a fetus weighs more than four pounds.
- During the ninth month from conception, a fetus gains half a pound per week. Of the 45 total generations of cell replication that will occur by mature adulthood, 41 have already taken place.