Showing posts with label China. Show all posts
Showing posts with label China. Show all posts

Sunday, December 8, 2013

Chinese Breast Cancer Trends

The latest meta-analysis from China shows that breast cancer is 44% more likely among Chinese women who have had one or more abortions. Critics claim this study is flawed because it relies on "case-control studies" which match a woman with cancer to a woman without cancer. The "recall bias" theory holds that women with cancer tend to tell the truth about their abortion history, while healthy women tend to conceal their abortions--even in China, where abortion is anything but "a private matter between a woman and her doctor."

It is easy to put the recall bias theory to the test. China has traditionally had a low breast cancer rate (only one out of forty Chinese women expect to get the disease, a mere fraction of the American rate).  If abortion does not increase the risk of breast cancer, tens of millions of Chinese abortions should have no impact on cancer incidence in China. But breast cancer in China is rising, and rising rapidly, as this public service simulation from General Electric shows.

This could be mere coincidence. Logicians recognize the post hoc ergo propter hoc fallacy--"after something, therefore because of something." There could be other causes of China's rising cancer rate. Oral contraceptives are known to have carcinogenic effects--but less than 2% of Chinese women have access to the Pill.

Perhaps pollutants are causing the increase. When the pesticide DDT breaks down to DDE, it mimics some of the effects of estrogen, leading some researchers to suspect it as a cause of cancer. China used to use DDT extensively in agriculture. If DDT caused breast cancer, one would expect peasant women in China to have elevated rates, while urban women might be spared. If abortion increases the risk of cancer, the results should be the opposite, because urban women in China are more likely to abort than peasant women are. As it turns out, breast cancer rates are rising more rapidly among urban women in China than among peasants.

Something is causing Chinese breast cancer cases to rise. It isn't the Pill, and it isn't DDT. What, then?

The latest meta-analysis says that women who choose abortion are 44% more likely to get breast cancer than do those that don't. Multiply that small number by millions and you get exactly what China is now experiencing--a rise in breast cancer all over the country with the highest rates in the urban centers.


Thursday, December 5, 2013

Chinese Abortions and American Health

In 1981, Dr. Malcolm Pike studied 163 Los Angeles breast cancer patients under the age of 33 and found that women who had used oral contraceptives were significantly more likely to get breast cancer than women who did not. The "relative risk" for women who had taken the Pill for six years of more was 2.2--which means they were twice as likely to get breast cancer as were women who did not take the Pill... with one exception. Women who had abortions (instead of relying on oral contraceptives) were even more likely to get breast cancer.

Pike did not zero in on abortions and the Pill because he disapproved of them on religious grounds, but because both of them expose a woman to estrogen. Estrogen has a well-documented impact on breast cancer risk. The Pill artificially adds estrogen to a woman from the outside, while pregnancy adds estrogen from the inside. Estrogen raises the risk of breast cancer in the 15 years after a normal birth, but the final stages of pregnancy mature the breast tissue so much that the overall effect of childbirth is to lower a woman's lifetime risk. Abortion leaves women with all the elevated risks of early pregnancy and none of the protective effects of third-trimester maturation.

The women in Pike's study were all under 32 when they got cancer. That's how many years have passed since Pike first published his findings. What has happened since then? Wikipedia lists 113 references on its "abortion/breast cancer hypothesis" page, and many of them show an elevated risk after abortion. The elevated risk is small, as these things go--a transient increase in risk of about 3% per week of terminated pregnancy. It takes a big study to turn something that small into a significant finding, and most of the big studies have been funded by big organizations, such as governments  and/or pharmaceutical companies.

To date, none of the studies funded by drug companies separate women who take oral contraceptives from women who have abortions. Imagine a tobacco company comparing lung cancer risks among pipe smokers to non-pipe-smokers without ever asking about cigarettes. That's what you get when a drug company simplistically compares women who terminated their pregnancy to women who avoided pregnancy... somehow. You have to ask about the Pill!

Not all studies have been funded by big drug companies, however, resulting in a steady drip of studies with elevated breast cancer risks after abortion. How can scientists ignore this? The answer is something called "recall bias." Abortion is such a private matter that healthy woman don't usually want to disclose it. All that changes when a woman gets cancer, however. If all the healthy women "forget" their abortions and all the sick women remember them, it would look like sick women had had more abortions even if they didn't really.

Between small numbers, recall bias, oral contraceptives, and the red-hot politics of abortion, all this can be confusing. Reasonable scientists have been able to disagree about the abortion/cancer link, and, as a result, American women have been choosing abortion for the last 32 years without finding out about this issue. But the latest research from China clears away the confusion.

Time Magazine reports that only 1.2% of Chinese women take the Pill, resulting in a lot of pregnancies. With China's "one-child per couple" policy, that has led to 13 million abortions every year. Unlike America, where these abortions are a "private matter between a woman and her doctor," Chinese data on abortions are kept by the same government agencies that conduct the procedures. With such huge numbers, official government data, and virtually no oral contraceptives, Chinese research on the abortion/breast cancer link should be as solid as research on living human beings can ever ethically be.

And the latest research devastates the claim that there is no link between abortion and breast cancer. The newest study from China perfectly matches the evidence from earlier studies suggesting that each week of a terminated pregnancy raises a woman's transient risk by approximately 3%. For a single abortion at 15-weeks, one would expect a 45% increase in risk. The meta-analysis reports a 44% rise. A second abortion would add more exposure, adding more risk. Two abortions in China leads to a 76% increase in risk. A third abortion would raise the risk even more--and Chinese women with three abortion had an average increased risk of 89%. This kind of "dose-response relationship" is very persuasive to open-minded researchers... especially when the "dose" is something with such a clear-cut relationship to breast cancer as estrogen.

Do you think this is going to change any medical minds? It will--but not in America any time soon. But that no longer matters. China has too many women and too many scientists to wait around for American "researchers" any longer.