Spontaneous abortions (miscarriages) are at least as common as induced abortions.
This work is a Venn diagram designed to illustrate the biology and sociology of abortion, both induced and spontaneous, in the United States. As detailed below, the central “embryonic” oval in the diagram contains sub-categorizations of all pregnancies in the US in recent years.
Spontaneous abortions, AKA miscarriages, are common. At least 21% of pregnancies abort spontaneously (gray ellipse highlighted below). This is usually due to genetic and developmental abnormalities. The large majority of these spontaneous abortions are experienced as “late periods”. If a woman is sexually active throughout her childbearing years and never uses birth control, it’s statistically likely that she’s had at least one if not more spontaneous abortions.
At least 35% (~ 1/3) of US women of childbearing age are opposed to abortion (gray oval highlighted below), leaving the remainder ( < 65%) as pro-choice. However, the proportion of pregnancies destined to miscarry is the same for both groups. As noted above, this is at least 21%.
Approximately 20% of pregnancies in the US end in induced, (or elective) abortion (gray ellipse highlighted below). The large majority of these of course occur among pro-choice women, but a small number ( < 5%?) of anti-abortion women do in fact have induced abortions.
On average, induced abortions occur at an earlier gestational age than spontaneous abortions. Therefore, a significant number of pregnancies ended by induced abortion would have ended later spontaneously. The reverse must also occur, albeit to a lesser extent: a certain percentage of pregnancies abort spontaneously and early, before the woman may have chosen to induce abortion.
Taking these scenarios together, it is estimated that ~13% of all abortions are inevitable, in that those pregnancies would end spontaneously or by choice, whichever came first. The gray area highlighted below shows this overlap between induced and spontaneous abortions.
As noted previously, a small percentage of women who oppose induced abortion have chosen to have at least one (small central gray area at right). For example, at least 20% of US women who’ve had induced abortions are Catholic. As with all abortions, a significant number of those induced abortions would have terminated later spontaneously (lower subdivision of gray area).
Additional Features of this Work
Venn diagrams are a useful way to illustrate both overlap and dissimilarity within categorical data sets. This Venn diagram was created with data from the references below using a “quantitatively conservative” approach, meaning that things are in general underestimated. For example, the overall miscarriage rate exceeds 21%, but it’s difficult to know by how much due to underreporting and undersampling error. The rate exceeds 50% in older childbearing women with large numbers of children. Another example: the percentage of pregnant US women opposed to abortion probably exceeds 35%. Some non-US references are cited concerning purely biological aspects of spontaneous abortion and/or as informative or historical resources on the topic of abortion in general.
The central “embryo” representing all pregnancies in the US is surrounded by a maroon-lined area, a “uterus” of sorts, which signifies all non-pregnant females in the US. The teal-lined area around that represents all males. The teal/male surround is not meant as some sort of patriarchal, protective envelope, but instead represents the insulation of males from the “heavy lifting” of procreation. Men don’t remember their singular direct experience with pregnancy and childbirth processes. Happy Birthday to them!
Thoughts and Questions Raised by the Data
Human conception is far from perfect. Conception is not the guaranteed beginning of a human life. It is the beginning of a chance at that life. Biology inevitably and frequently terminates pregnancies to cull genetic mistakes with little or no chance of proper development and survival, and for other less common reasons (maternal illness, infection, uterine anomalies, etc.). Women choose to end pregnancies if they aren’t prepared to complete the pregnancy and then raise a child or cede it to others.
What does all this mean for religious or other opposition to abortion?
Does human existence (having a soul, etc.) truly begin at conception, or sometime later?
If later, then when? Second trimester, or third? Birth??
Who exactly decides this, and on what basis?
If human existence does begin at conception, then is all abortion murder, including miscarriage? But there is no killer! Miscarriages are by definition spontaneous, so prospective mothers don’t cause them.
What about women considering induced abortion?
Does the frequency of spontaneous abortions automatically license women to terminate potentially viable pregnancies?
Who is best qualified to judge a woman’s emotional, spiritual, physical, and socioeconomic ability to attempt to gestate, deliver, and then raise a child or relinquish it to another fate?
Should women be required to follow beliefs / opinions about when human existence begins that differ from their own?
What do you think?
The story behind the work
I became vehemently opposed to abortion in high school. My opposition was based on a belief that human life begins at conception.
As a college freshman at SMU, I had this fantastic English teacher, Jane Albritton. One of our assignments was to:
1: Identify a topic about which we held strong opinions and deep-rooted feelings,
and then,
2. Research the topic and write an essay defending the opposite viewpoint to our opinion, with references.
I chose abortion as my topic. The rest, as they say, is history.
My research revealed the stark truth that a huge percentage of conceptions abort spontaneously, very often before the woman even knows she’s pregnant. This completely exploded my ignorant presumption that every human conception represented the beginning of an independent human existence. Far from it. By the time I turned in my essay, I was unequivocally “pro-choice”.
Yes, a human life may indeed begin at conception, but the converse is not necessarily true: conception in no way guarantees the beginning of a human life.
The research I did over 40 years later for this artwork forced me again through the thought processes I underwent back then. Little has changed, including the need for people to educate themselves about opinions they hold.
Acknowledgements
We sincerely thank Richard Del Cristo, Jr. for his insightful comments on this work.
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Poll: Majority Want To Keep Abortion Legal, But They Also Want Restrictions
The Problem of Spontaneous Abortion: Is the Pro-Life Position Morally Monstrous?
‘Miscarriage or abortion?’ Understanding the medical language of pregnancy loss in Britain; a historical perspective
Reproductive autonomy and the ethics of abortion
#abortion #prochoice #anti-abortion #prolife #miscarriage #medicalethics #religion #patriarchy