Carcinogens and the Abortion-Breast Cancer Link (Hint: Abortion Does Cause Breast Cancer)

Coalition on Abortion/Breast Cancer ^ | May 20, 2003 | Karen Malec

[Saundra Duffy]

From: The Pro-Life Infonet

Carcinogens and the Abortion-Breast Cancer Link By Karen Malec

[Pro-Life Infonet Note: Karen Malec is the president of the Coalition on Abortion/Breast Cancer.]

An official list of "known human carcinogens" released by the Department of Health and Human Services in December 2002 includes steroidal estrogens for the first time. The Report on Carcinogens states that steroidal estrogens are used in estrogen replacement therapy (ERT) and common abortifacient drugs. Both kinds of drugs have been widely utilized by American women. The federal report is available on the National Institute of Environmental Health Sciences website. [1]

While certain pharmaceuticals might provide limited medical benefits, women must balance these considerations against the fact that breast cancer is the second greatest cause of cancer among American women. Clearly, the Report on Carcinogens presents a serious conflict for the National Cancer Institute (NCI), an agency of the Department of Health and Human Services. In February, a panel of grant-dependent scientists chosen by the NCI swept under the rug staggering biological and epidemiological evidence supporting a causal relationship between abortion and breast cancer which has been amassed over the last 46 years.

What do ERT and abortifacient drugs have to do with the abortion-breast cancer (ABC) link? Estrogen overexposure provides the biological explanation for most of the risk factors for breast cancer, including abortion. Estrogen is known to increase the rate of cell division. It causes normal and pre-cancerous cells to multiply. A few days after conception, estrogen levels start climbing, so that by the end of the first trimester, a mothers estrogen level is increased 2000% and her breasts are swollen. Scientists theorize that only a third trimester process, differentiation (maturation of cells), neutralizes the mothers exposure to estrogen and provides her with increased protection against breast cancer.

A booklet published by the Breast Cancer Prevention Institute, "Breast Cancer Risks and Prevention", explains the critical importance of an early first full term pregnancy (before age 25). This influences breast cell maturity and, consequently, a womans lifetime risk for the disease. The booklet says:

"If a woman does not have a full-term pregnancy (meaning she is childless or nulliparous), she has increased risk for breast cancer, since she never develops (mature, cancer-resistant) type 3 and 4 lobules. If she has children later in life (after age 30), she has increased risk, because, for most of her menstrual life, her estrogen has been stimulating immature (cancer-vulnerable) type 1 and 2 breast lobules. If she has children as a teenager, she has decreased risk of breast cancer, since her breast tissue matures very early in her menstrual life to type 3 and 4 lobules." [2]

Similarly, women who experience more menstrual periods during their lives are at greater risk. Why? With each monthly period, theyre exposed to more estrogen. This is why the risk is greater for women who have fewer or no children, who breastfeed little or not at all, who experience late menopause or early onset of menstrual periods and who delay their first full term pregnancies.

On the other hand, alcohol consumption, lack of exercise and obesity each increase breast cancer risk because they cause a womans estrogen levels to be elevated.

Use of diethylstilbestrol (DES) has been linked with increased risk. It is a synthetic estrogen given to diabetic pregnant women at risk for miscarriage starting in the 1940s. For almost 25 years, researchers told women there was no link between DES and breast cancer. However, because the disease develops slowly over time, it took 20 years before researchers were able to detect a trend in the direction of increased risk.

Chris Kahlenborn, M.D. wrote in his book, Breast Cancer: Its Link to Abortion and the Birth Control Pill, that "The risk of DES appears to be greatest in women older than 60." [3]

A similar trend can be observed among women of the Roe v. Wade generation. A Report to the Nation on the Status of Cancer for the period 1973 to 1998 from the National Cancer Institute and other agencies reveals that an increasing incidence of breast cancer could be observed starting in 1987 14 years after the legalization of abortion. [4] A graph provided by the reports authors, figure 3, clearly shows that the more than 40% increase in breast cancer rates since 1987 was sustained solely by the youngest of three generations the Roe v. Wade generation.

Just as the risk of breast cancer increases as DES users age, the incidence of the disease is just as likely to rise as the Roe generation ages.

What's the bottom line? Women have become scientists human guinea pigs. The National Cancer Institute and private cancer organizations are to blame for the nations out-of-control breast cancer rates. If they really wanted women to know the truth about the ABC link, they would have informed women of the existence of the ongoing research in 1973 when abortion was legalized.

This is why the NCIs leaders were afraid to debate the evidence during its workshop earlier this year. They knew they would lose.

References 1. See http://www.niehs.nih.gov/oc/news/10thrc.htm (December 11, 2002) Visited May 20, 2003.

2. Lanfranchi A, Brind J. Breast Cancer Risks and Prevention. Breast Cancer Prevention Institute (2002) P. 8.

3. Kahlenborn C. Breast Cancer: Its Link to Abortion and the Birth Control Pill. One More Soul. New York, New York. (2000) P. 183.

4. Howe HL, Wingo PA, Thun MJ, Ries LA, Rosenberg HM, Feigal EG, Edwards BK. Annual report to the nation on the status of cancer, 1973 through 1998, featuring cancers with recent increasing trends. J Natl Cancer Inst 2001;93:824-842.

[Saundra Duffy]

Just more proof that women are being exploited by the abortion industry. "Keep 'em ignorant!" They're laughing all the way to the bank.

[Saundra Duffy]

Partial ping

[Koblenz]

I still think that moral, and not medical, arguments will carry the day in the abortion debate. Medical issues such as the breast cancer link don't really belong in the political arena...

[Saundra Duffy]

Another ping

[WilliamWallace1999]

Early pregnancy in life has a PROTECTIVE EFFECT on the breasts. That does not mean that abortion cause breast cancer, abortion kills a baby and ends a pregnancy. The leap of logic to conclude that abortion causes breast cancer would also have to be applied to this theorem, ABSTINENCE CAUSES BREAST CANCER which is a true statement with you twisted statistics. Women who abort and kill their babies do not have a higher rate of breast cancer than women who have never been pregnant, that is the control group. You can't use knocked up teen moms having babies on Medicaid, soaking up foodstamps, and eating govenment cheese as the control group.

That is the lapse in logic that lead to the discounting of the abortion-breast cancer linkage. The whole topic was a waste of energy and undermined the solid and logical arguments against abortion LIKE IT IS MORALLY WRONG. Instead the pro-life forces have been exposed as prevaricatiors and have lost legitimacy in the publics eye. The movement should have chosen a different battle.

[eboyer]

They also show similar links to breast cancer in women that choose to not breast feed except I remember the numbers being higher.

[Coleus]

Since 1957, there have been 28 studies linking abortion to breast cancer. It's old news but the liberals and demons in the press, schools and democrat party have been supressing this information!

http://www.abortionbreastcancer.com/ABC_Research.htm

http://www.realage.com/news_features/tip.aspx?cid=13400&ref=1

http://www.breastthermography.org/ instead of mammography

http://www.mercola.com/2002/mar/23/omega3.htm
http://www.mercola.com/2002/jun/5/fish_oil.htm

http://www.merck.com/pubs/mmanual/section18/chapter242/242c.htm

http://www.cancermed.com/
http://www.cancerdecisions.com/


“According to Dr. Joel Brind, President of the Breast Cancer Prevention Institute, there is a 30% increased risk of breast cancer linked with abortion among the general public. Presently this translates into an additional 5000 -8000 cases of breast cancer per year, however by the year 2020, this number may be as high as 40,000 - 50,000,”

[Coleus]

Abstinence doesn't cause increased rates of breast cancer. The hormones used for gestation are still in full production when a baby is aborted. This is the reason why the cancer rates increase, these hormones produce the growth of cells and when there is no baby in utero to grow these hormones work on other cells thus the increase in cancer.

I know for a fact doing sidewalk counseling that the health risks to women associated with abortion have led to a number of "saves".

So, what "battle" do you propose that we do?

[valkyrieanne]

Very good points. To get a full picture, you have to compare women who have never been pregnant, ever, yet who are physically healthy (i.e. who don't have some other medical problem that would make them have cancer in later life) with women who are also healthy but have had at least one abortion - and *no* further children. For the first group, I would think nuns would be an excellent demographic. (From what I've read, nuns have a higher rate of female cancers in general than women as a whole.)

Nor do I think this article is accurate regarding the protective value of pregnancy over age 30. From what I've read, having several children over age 30 and breastfeeding them *does* give some protection against later breast cancer.

Further, any study done *must* distinguish between pre-menopausal & post-menopausal breast cancer. They are radically different diseases even though they have the same effect. Similarly, you have to control for genetics (i.e. the presence of the identified cancer genes), and lifestyle indicators that lead to breast cancer as well.

I'm not sure how much teenage pregnancy really protects against breast cancer, since there are so many *other* cancer risks correlated with teenage pregnancy: illegitimacy, poverty, poor access to health care, obesity, use of hormonal birth control (like Norplant), exposure to drugs and alcohol.

Somehow I don't think these controls have been, or are being considered. I too oppose abortion because it kills a baby, but dubious science isn't the way to convince people.

[valkyrieanne]

Abstinence doesn't cause increased rates of breast cancer. The hormones used for gestation are still in full production when a baby is aborted. This is the reason why the cancer rates increase, these hormones produce the growth of cells and when there is no baby in utero to grow these hormones work on other cells thus the increase in cancer.

The way it works is this. Every month, estrogenic hormones stimulate a woman's ovaries to make an egg "mature" and be released. Those same estrogens also stimulate the breast, on a monthly basis. This monthly stimulation going on for year after year *does* form a significant breast cancer risk. If a woman never has a child, assuming she's healthy otherwise, she has a higher risk of breast cancer than a woman who's had at least one child.

So yes, complete abstinence from childbearing throughout life *does* pose a cancer risk. Our "ideal" human pattern (which we don't live out because it's largely incompatible with our economic and social system) is for girls to be married several years after their first period, and to either be pregnant or nursing almost continuously until their forties. In this scenario, a woman will have very few periods - maybe a couple every 3-4 years at most. As it is, women have far more periods throughout their life than nature "intended" for them to have, and there are health consequences.

Is this cancer risk greater, less than, or the same as the supposed risk from abortion? I don't know, because to my knowledge this comparison hasn't been done.

[farmfriend]

I've sent this article to our health committee. Thanks for the post.

[Aquinasfan]

"If a woman does not have a full-term pregnancy (meaning she is childless or nulliparous), she has increased risk for breast cancer, since she never develops (mature, cancer-resistant) type 3 and 4 lobules.

Another indication that pregnancy represents a state of health and that anything that externally interferes with the pregnancy represents a health threat. The same generally holds true with artificial means of contraception.

[Saundra Duffy]

the liberals and demons in the press, schools and democrat party have been supressing this information!

No kidding.

[Saundra Duffy]

I've sent this article to our health committee.

Excellent, Sis. (Miss you.)

[Saundra Duffy]

Medical issues such as the breast cancer link don't really belong in the political arena...

That doesn't make sense, pal.

[farmfriend]

Are you guys coming up for the rally this weekend?

[Coleus]

I know a lot of Catholic Nuns who live to ripe old ages in their 80's +. Sure, some get cancer, it's part of aging, but most live a long time. I'm sure there are epidemiological studies out there comparing celibate women to those who bear children and those who had abortions.

Is this cancer risk greater, less than, or the same as the supposed risk from abortion? I don't know, because to my knowledge this comparison hasn't been done.>>>>

Mabye you can e mail those on the this website for further information. http://www.abortionbreastcancer.com/

[Canticle_of_Deborah]

bump!

[HairOfTheDog]

The whole topic was a waste of energy and undermined the solid and logical arguments against abortion LIKE IT IS MORALLY WRONG. Instead the pro-life forces have been exposed as prevaricatiors and have lost legitimacy in the publics eye. The movement should have chosen a different battle.

Good post.

Feigned concern for women getting breast cancer is laughable as a reason to argue against abortion.

[Mamzelle]

Agreed--this line of reasoning muddies many waters, and chiefly serves to raise alarm in women who are childless, who had children late in life, or even had a *natural* miscarriage.

Does this weaken or strengthen the pro-life position...?

[DaGman]

More junk science. I'll believe this when they show a connection between pregnacy and breast cancer. Until then, its nothing but junk science based on religious beliefs, IMHO.

[anniegetyourgun]

The only folks politicizing this issue are from the abortion industry who wish to keep women uninformed.

[HairOfTheDog]

It only makes my heart and mind wonder why they are reaching for some abstract reason to not have an abortion, when the baby is obviously the single most important issue, for both the woman, and the pro-lifer.

Every woman over 40 in my family got breast cancer and I most likely will too. All lived through it, though a few got other cancers later. For people to isolate one cause in a vacuum and not pretend that there are a multitude reasons people get breast cancer, and a myriad of other priorities, fears and decisions going on in the mind of a person considering abortion; realities that are much more 'here and now' than some future risk of breast cancer. It doesn't even register on the radar.

[Coleus]

We've had 118 "saves" this past year at an abortion clinic touting the health risks associated with the procedure including: breast cancer links, infertility, death, bleeding, infections, etc.

It's a tool, there is nothing "made up" which is used to save children from death and it works.

What arguments do you use?

[VeritatisSplendor]

More junk science. I'll believe this when they show a connection between pregnacy and breast cancer. Until then, its nothing but junk science based on religious beliefs, IMHO.

Didn't you READ? It isn't pregnancy that causes the increased risk of breast cancer, it's the INTERRUPTION of pregnancy. Saying you won't believe there's a connection between abortion and breast cancer until they establish a connection between pregnancy and breast cancer is just silly -- normal pregnancies are PROTECTIVE against breast cancer because of the changes in breast tissue that occur during the third trimester of pregnancy.

The logic of your comment is akin to that in "I won't believe there's a connection between drunk driving and increased risk of death until someone shows there's a connection between alcohol consumption and increased risk of death".

[mabelkitty]

I've always considered this my personal "tin foil beanie" conspiracy for several years now.

It just makes perfect sense.

[mabelkitty]

The breasts experience dramatic changes during pregnancy. Just because you can't notice it with the human eye does not mean it is taking place.

To abruptly rip a healthy fetus and interrupt a healthy pregnancy of course would have a devastating affect on the body.

When a fetus is preparing itself for miscarriage, the body makes the changes for the sad event. Talk to any woman who has had one, and she will tell you that somehow she "just knew" it was going to happen.

[Alamo-Girl]

Thanks for the heads up!

[jlogajan]

We've had 118 "saves" this past year at an abortion clinic touting the health risks associated with the procedure including: breast cancer links, infertility, death, bleeding, infections, etc.

It's a tool, there is nothing "made up" which is used to save children from death and it works.

Of course lies work. They're still lies. The maternal mortality rate for full term deliveries is EIGHT times higher than the case mortality rate for induced abortion.

So your little lies are convincing women to increase their chances of death by 800%. Liar.

[MrLeRoy]

Women who abort and kill their babies do not have a higher rate of breast cancer than women who have never been pregnant

Provide evidence for your claim.

[jlogajan]

Women who abort and kill their babies do not have a higher rate of breast cancer than women who have never been pregnant

Provide evidence for your claim.

The Denmark study, largest of its kind, studied millions of women's health records and found no link between abortion and breast cancer. This study eliminated "recall bias" in which healthy women tend to not report having had abortions. "Recall bias" screwed up all the earlier studies that claimed to have found a link between breast cancer and abortion. Once recall bias was eliminated, the link disappeared.

[nickcarraway]

BUMP

[Coleus]

Your stats are made up, talk about lying.

[WilliamWallace1999]

"I know for a fact doing sidewalk counseling that the health risks to women associated with abortion have led to a number of "saves". "


How about the truth. That God loves that baby and the woman too. Abortion is the taking of a human life. That all life is sacred and must be protected. That it is a child not a choice.

I applaud and thank you for your effort to save the unborn children. As a Catholic, I agree with you. As a pro-life Board Certified Ob/Gyn, I just can't let scientific half-truths go unchallenged. Medical research today is full of bullshit artists that spin data to meet an agenda. Hypothesis must pass statistical analytical muster or they are only propaganda and will ultimately undermine the credibility of the cause.

[MrLeRoy]

The Denmark study, largest of its kind, studied millions of women's health records and found no link between abortion and breast cancer. This study eliminated "recall bias" in which healthy women tend to not report having had abortions.

"from what I could gather from Dr. Melbye's update of his Danish data (during the question and answer session), his stratification of relative risk by age in 1973 (date of inception of his abortion registry) was not accomplished by restricting the initial analysis to different sub-cohorts. For example, he did not reanalyze the data from scratch using only women born since 1950 (instead of 1935), thus eliminating most of the misclassified women from the analysis. Rather, he applied a statistical adjustment to the initial analysis of the entire cohort. Consequently, the large distortion of the relative risk estimate in the direction of underestimation, which we have pointed out (Brind and Chinchilli, 1997), still applies." - "Early Reproductive Events and Breast Cancer: A Minority Report," Joel Brind, Ph.D., Professor, Human Biology and Endocrinology, Baruch College-CUNY

[WilliamWallace1999]

Actually, you and the other proponents of this theory are the one's required to statistically provide the evidence. I was proposing the null hypothesis to your hypothesis. The burden of proof in research is on the party making the claim of causation in response to a statistical linkage. Equating correlation with causation is one of the oldest mistakes in research. It is avoided by forming a null hypothesis and then failing to refute it. If efforts to refute the null hypothesis succeed, then the presumption is that the theorem is correct.

[MrLeRoy]

Women who abort and kill their babies do not have a higher rate of breast cancer than women who have never been pregnant

Provide evidence for your claim.

I was proposing the null hypothesis to your hypothesis.

You didn't "propose" it but stated it as established fact. Thanks for clarifying your meaning.

[Coleus]

As a pro-life Board Certified Ob/Gyn>>>>

So tell me more. The is no correlation at all? Where can I get the facts? I've been trying to get them.

http://www.freerepublic.com/focus/f-news/864260/posts?page=4#4

[WilliamWallace1999]

http://www.cancer.org/docroot/CRI/content/CRI_2_6x_Can_Having_an_Abortion_Cause_or_Contribute_to_Breast_Cancer.asp?sitearea=

Can Having an Abortion Cause or Contribute to Breast Cancer?

Research studies have not found a cause-and-effect relationship between breast cancer and abortion. There are different types of abortion:

Induced abortion is probably what most people consider "abortion," in that a woman chooses to end a pregnancy.
Spontaneous abortion, which most people refer to as a miscarriage, also causes the interruption of hormones. It is this interruption which is believed to increase ones' risk of developing breast cancer.
Stillborn births, in which the fetus dies after five months gestation while still in the uterus, may cause hormonal fluctuations in the mother that are abnormal when compared to a normal, full-term pregnancy.
All of these situations have been studied to see what effect they may have on the woman's risk of developing breast cancer later in life. No link has been found between breast cancer and miscarriage or stillbirths. The research is not quite so clear with induced abortions and breast cancer.

Before 1973, induced abortions were illegal in the United States, except in some states. Therefore, when researchers ask about a woman's reproductive past, women may be not want to disclose the fact that they have had an illegal abortion. Even though abortion is now legal, it is still a very personal, private matter that many women are hesitant to talk about. Studies have shown that healthy women are less likely to report their histories of induced abortions. In contrast, women with breast cancer are more likely to accurately report their reproductive histories because they are literally searching their memories for anything that may have contributed to their disease.

The likelihood that women who have breast cancer will give a more complete account of their abortions than women who do not have breast cancer is called "recall bias" and it can seriously undermine the accuracy of study results.

Most early studies of abortion and breast cancer used a case-control study design, one that is very prone to recall bias. In these studies,women with and without breast cancer were asked to report past abortions and the frequency of abortions in women with breast cancer and the disease-free controls was compared. It is likely that the small increases in breast cancer risk observed in many of these studies were not authentic findings because of recall bias.

A prospective study design is stronger and less prone to bias. In this type of study a population of women who are cancer-free are asked about their past abortions and then observed to see if a new cancer occurs In this type of study, there is no chance that having the disease will influence a woman’s memory of past abortions or willingness to report past abortions.

Some prospective studies have solved the problem of recall bias by using innovative ways to document induced abortions. For example, a recent study used birth certificates of children born to women with breast cancer to identify women who had had induced abortions (the number of previous pregnancies and their outcomes were listed on these birth certificates). This study found no increase in breast cancer risk in women whose abortion is followed by a live birth.

The largest, and probably the most reliable, study of this topic was conducted recently in Denmark. In that study, all Danish women born between 1935 and 1978 (1.5 million women) were linked with The National Registry of Induced Abortions and with the Danish Cancer Registry. So, all information about their abortions and their breast cancer came from registries, was very complete, and was not influenced by recall bias. After adjusting for known breast cancer risk factors, the researchers found that induced abortion(s) had no overall effect on the risk of breast cancer. In this very large group of women, 1,338 cases of breast cancer occurred in women who had terminated pregnancies. The size of this study and the manner in which it was conducted provides substantial evidence that induced abortion does not affect a woman's risk of developing breast cancer.

There are other, smaller studies pointing to the fact that abortion does not cause, nor contribute to, the development of breast cancer.

The topic of abortion and breast cancer highlights many of the most challenging aspects of epidemiologic studies of human populations and how those studies do or do not translate into public health guidelines. The issue of abortion generates passionate personal and political viewpoints, regardless of any possible disease connection. Breast cancer is the second most common cancer in women, and it can be a life-threatening disease that most women fear. Still, the public is not well-served by false alarms, even with both the exposure and the disease are of great importance and interest to us all. At the present time, the scientific evidence does not support a causal association between induced abortion and breast cancer.

[MrLeRoy]

Women who abort and kill their babies do not have a higher rate of breast cancer than women who have never been pregnant, that is the control group. You can't use knocked up teen moms having babies on Medicaid, soaking up foodstamps, and eating govenment cheese as the control group.

Do food stamps and government cheese protect against breast cancer? If not, why bring them up?

[MrLeRoy]

See post 35 on this "reliable" study.

"The largest, and probably the most reliable, study of this topic was conducted recently in Denmark. In that study, all Danish women born between 1935 and 1978 (1.5 million women) were linked with The National Registry of Induced Abortions and with the Danish Cancer Registry. So, all information about their abortions and their breast cancer came from registries, was very complete, and was not influenced by recall bias. After adjusting for known breast cancer risk factors, the researchers found that induced abortion(s) had no overall effect on the risk of breast cancer. In this very large group of women, 1,338 cases of breast cancer occurred in women who had terminated pregnancies. The size of this study and the manner in which it was conducted provides substantial evidence that induced abortion does not affect a woman's risk of developing breast cancer."

[MrLeRoy]

even a 1998 CME review article [Bartholomew & Grimes, “The Alleged Association Between Induced Abortion and Risk of Breast Cancer: Biology or Bias?”, 53 Obstetrical & Gynecological Survey, 708, 710-11 (1998)] which treated the Melbye study as one of the "most rigorous . . . available" admitted that it has "several [methodological] limitations," and is "not definitive."

[WilliamWallace1999]

Here is another interesting diatribe on the subject. If only Dr. Brind would apply his statistical buzzsaw to the case-controlled studies that attempt to support the connection. This is another type of intellectual dishonesty. One must apply the same standards to all research studies, not just shred the ones that don't fit within your paradigm:

http://www.pregnantpause.org/safe/abcdane.htm

The New England Journal of Medicine recently published a Danish abortion study by Melbye et al. The lead author told the Wall Street Journal: "I think this settles it definitely. There is no overall increased risk of breast cancer for the average woman who has an abortion." In an accompanying editorial an official of the National Cancer Lnstitute stated, "The clear central finding is that there is no overall risk." The pro-abortion media picked up this description of the study and headlined it across this nation and the world. It was exactly what they wanted to hear, and they swallowed these comments without any attempt to evaluate whether or not they were valid.
We now have an exhaustive study of this research article by the man who is probably the most qualified judge of the validity of such studies in the world, Dr. Joel Brind. Let's mention a few obvious problems.


Of the 1.5 million women studied, 1.2 million had neither any exposure to induced abortion nor have developed breast cancer.
Of the 281,000 women who did have an induced abortion, most are still too young to have developed breast cancer, and some are still teenagers.
Of the 10,000 women who have developed breast cancer, most are too old to have their abortion histories on record, as the Danish Registry only goes back to 1973, about when abortion was legalized. At that time the oldest women were already 38 years old.
Of the 1,338 women who had abortions and did develop breast cancer, 81% had their abortion recorded at age 30 or over, and 54% at age 35 or over. As we know, by far, most abortions are done on younger women. The women younger than 30 years who developed breast cancer are only listed as having breast cancer without any record of having had abortions. Other equally important data is omitted or de-emphasized. There were a few women who had abortions as teenagers who had already developed breast cancer, and they had a 29% increased risk, but they were too few in number to be statistically significant.
The study did demonstrate a statistically significant trend of a 3% risk increase for each additional week of gestation before abortion. This rose to an 89% increased risk for abortions after 18 weeks. Interestingly, this finding in the study was not mentioned in the study's "conclusions".
Much data was missing from the paper, particularly the effect of other independent variables.
Previous studies confirming a relationship between abortion and breast cancer are attacked or misrepresented.
There is an egregious distortion of the age distribution of abortion clients.
The author falsely misrepresents other medical studies, saying that his "result" is very much in line with the results of previous retrospective cohort studies. Actually, three of the four such studies he cites are entirely irrelevant. Two of these concern only miscarriages, and the third almost entirely so while not presenting any data relating specifically to induced abortion.
The author attacks the Brind meta-analysis, which was published last fall, as unreliable due to "response bias". Such criticism has been thoroughly discredited in a number of major studies. He criticizes Brind's meta-analysis as being from 30 studies, when in fact it analyzed the entire world literature of more than twice that number.

[gcruse]

Our prayers for breast cancer are having an effect.
I'm doubling my efforts to include lung cancer
in marijuana smokers. Hope you will join me.

[WilliamWallace1999]

You are correct, but the case-controlled studies that support the link are even less statistically significant. I don't care what field of research it is, case-controlled studies are only one step above single case reports in importance. The only way one can get a case-controlled study published is if their is an absolute dirth of literature on the topic. Medical research is a dynamic process. There is no such thing as a conclusive study. It is continuous process of challenging the conclusions of others.

[MrLeRoy]

You are correct, but the case-controlled studies that support the link are even less statistically significant.

To the extent they're plagued by recall bias, yes.

Has the existence of systematic recall bias been shown, or is it a theoretical flaw?

[MHGinTN]

Since you're so sure of your assertion, would you mind posting the link to read your basis for the assertion? ...The maternal mortality rate for full term deliveries is EIGHT times higher than the case mortality rate for induced abortion. jlogajan Where could I read the data spread sheets for that assertion you offer?

[MHGinTN]

Incidentally, because of your BIAS toward defending the slaughter of babies waiting to be born, you no doubt omit the stat for every baby killed in the abortions, right? ... Because that raises the mortality with someone besides the woman hiring the serial killer to 'end the pregnancy'. Somehow I just knew you'd make that specious omission, ghoul.

[RJCogburn]

Just more proof

Not so fast.

ERT studies have all, to my knowledge been done with oral estrogen which has a'first pass' through the liver before going to the breast and elsewhere.

What about transdermal estrogens which go directly into the bloodstream bypassing any liver effect. There is no proof that ERT in that case has an increased incidence. That more closely mirrors endogenous estrogens, btw.

[WilliamWallace1999]

Case controlled studies are statistically less significant regardless of the topic. The recall bias issue in this case was advanced as a possible source of error, but what I refer to is the nature of different study types with the double blind trial as the gold standard and the case-controlled study as the least reliable.

From the Skeptics Dictionary:

control group study, double-blind and random tests
A control group study uses a control group to compare to an experimental group in a test of a causal hypothesis. The control and experimental groups must be identical in all relevant ways except for the introduction of a suspected causal agent into the experimental group. If the suspected causal agent is actually a causal factor of some event, then logic dictates that that event should manifest itself more significantly in the experimental than in the control group. For example, if 'C' causes 'E', when we introduce 'C' into the experimental group but not into the control group, we should find 'E' occurring in the experimental group at a significantly greater rate than in the control group. Significance is measured by relation to chance: if an event is not likely due to chance, then its occurrence is significant.

A double-blind test is a control group test where neither the evaluator nor the subject knows which items are controls. A random test is one which randomly assigns items to the control or experimental groups.

The purpose of controls, double-blind and random testing is to reduce error, self-deception and bias. An example should clarify the necessity of these safeguards.

The DKL LifeGuard Model 2, from DielectroKinetic Laboratories, can detect a living human being by receiving a signal from the heartbeat at distances of up to 20 meters through any material, according to its manufacturers. Sandia Labs tested the device using a double-blind, random method of testing. Sandia is a national security laboratory operated for the U.S. Department of Energy by the Sandia Corporation, a Lockheed Martin Co. The causal hypothesis they tested could be worded as follows: the human heartbeat causes a directional signal to activate in the Lifeguard, thereby allowing the user of the LifeGuard to find a hidden human being (the target) up to 20 meters away, regardless of what objects might be between the LifeGuard and the target.

The testing procedure was quite simple: five large plastic packing crates were set up in a line at 30-foot intervals and the test operator, using the DKL LifeGuard Model 2, tried to detect in which of the five crates a human being was hiding. Whether a crate would be empty or contain a person for each trial was determined by random assignment. This is to avoid using a pattern which might be detected by the subject. Their tests showed that the device performed no better than expected from random chance. The test operator was a DKL representative. The only time the test operator did well in detecting his targets was when he had prior knowledge of the target's location. The LifeGuard was successful ten out of ten times when the operator knew where the target was. It may seem ludicrous to test the device by telling the operator where the objects are, but it establishes a baseline and affirms that device is working. Only when the operator agrees that his device is working should the test proceed to the second stage, the double-blind test. For, the operator will not be as likely to come up with an ad hoc hypothesis to explain away his failure in a double-blind test if he has agreed beforehand that the device is working properly.

If the device could perform as claimed, the operator should have received no signals from the empty crates and signals from each of the crates with a person within. In the main test of the LifeGuard, when neither the test operator nor the investigator keeping track of the operator's results knew which of five possible locations contained the target, the operator performed poorly (six out of 25) and took about four times longer than when the operator knew the target's location. If human heartbeats cause the device to activate, one would expect a significantly better performance than 6 of 25, which is what would be expected by chance.

The different performances--10 correct out of 10 tries versus 6 correct out of 25 tries--vividly illustrates the need for keeping the subject blind to the controls: it is needed to eliminate self-deception and subjective validation. The evaluator is kept blind to the controls to prevent him or her from subtly tipping off the subject, either knowingly or unknowingly. If the evaluator knew which crates were empty and which had persons, he or she might give a visual signal to the subject by looking only at the crates with persons. To eliminate the possibility of cheating or evaluator bias, the evaluator is kept in the dark regarding the controls.

The lack of testing under controlled conditions explains why many psychics, graphologists, astrologers, dowsers, paranormal therapists, etc., believe in their abilities. To test a dowser it is not enough to have the dowser and his friends tell you that it works by pointing out all the wells that have been dug on the dowser's advice. One should perform a random, double-blind test, such as the one done by Ray Hyman with an experienced dowser on the PBS program Frontiers of Science (Nov. 19, 1997). The dowser claimed he could find buried metal objects, as well as water. He agreed to a test that involved randomly selecting numbers which corresponded to buckets placed upside down in a field. The numbers determined which buckets a metal object would be placed under. The one doing the placing of the objects was not the same person who went around with the dowser as he tried to find the objects. The exact odds of finding a metal object by chance could be calculated. For example, if there are 100 buckets and 10 of them have a metal object, then getting 10% correct would be predicted by chance. That is, over a large number of attempts, getting about 10% correct would be expected of anyone, with or without a dowsing rod. On the other hand, if someone consistently got 80% or 90% correct, and we were sure he or she was not cheating, that would confirm the dowser's powers.

The dowser walked up and down the lines of buckets with his rod but said he couldn't get any strong readings. When he selected a bucket he qualified his selection with something to the effect that he didn't think he'd be right. He was right about never being right! He didn't find a single metal object despite several attempts. His performance is typical of dowsers tested under controlled conditions. His response was also typical: he was genuinely surprised. Like most of us, the dowser is not aware of the many factors that can hinder us from doing a proper evaluation of events: self-deception, wishful thinking, suggestion, unconscious bias, selective thinking, subjective validation, communal reinforcement, etc.

Many control group studies use a placebo in control groups to keep the subjects in the dark as to whether they are being given the causal agent that is being tested. For example, both the control and experimental groups will be given identical looking pills in a study testing the effectiveness of a new drug. Only one pill will contain the agent being tested; the other pill will be a placebo. In a double-blind study, the evaluator of the results would not know which subjects got the placebo until his or her evaluation of observed results was completed. This is to avoid evaluator bias from influencing observations and measurements.
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