This week has seen the observance of the UN’s World Cancer Day(February 4) highlighting the priority that the UN has given to reducing the global burden of this disease. Each year about 14 million people worldwide learn they have cancer and 8 million people die from the disease. Among the 14 million are around 1.7 million women who find they have breast cancer, which is the second most commonly diagnosed cancer. Lung cancer is the first – and most deadly.
Because it affects almost exclusively women, breast cancer has a higher political and media profile – helped along by the Angelina Jolies of the world — than the more ubiquitous lung cancer. Many countries have breast cancer screening programmes, free to women over 50 (who have the greatest risk), to detect signs of the disease early and allow treatment. This is partly why a smaller proportion of people die from it than from lung cancer (9 percent compared with 19 percent).
Public funds are poured into research on treatments and risk factors. In Britain, where 49,500 new cases are diagnosed annually and 11,600 women die from breast cancer, a million women were recruited from the National Health Service (NHS) Breast Screening Programme between 1995 and 2001 for a prospective study. The Million Women Study provides a database for researchers trying to nail down various causes of the most common cancer among women. Health authorities are concerned about its growing incidence among younger British women. Some scientists are working on a vaccine against this stubborn disease. All this and much more you can learn from leading news sources any day of the week.
So why the deathly silence about a Chinese study published in a mainstream cancer journal in November and confirming one of the disputed risk factors for breast cancer?
In “A meta-analysis of the association between induced abortion and breast cancer risk among Chinese females,” published in the journal Cancer Causes Control, epidemiologist Yubei Hunag and colleagues reviewed 36 studies that investigated this link and found: among women who had only one abortion, an overall increased risk of developing breast cancer of 44 percent; after two abortions the risk increased by 76 percent, and after three abortions by 89 percent. The more abortions, the higher the risk. This is at least page 3 news.
But Google the terms “China” “breast cancer” and “abortion” and you won’t find anything in the first forty results from the New York Times or the UK Guardian or the Sydney Morning Herald about the Tianjin Medical University study. It has been left to pro-life groups and Christian broadcasters to circulate.
Is the news blackout because what happens to Chinese women could not possibly be relevant to British or American or Australian women? Or is it because abortion has become the foundation on which the whole western edifice of “reproductive health” rests, and without which a new cultural revolution would be necessary?
Two reproductive revolutions
China and the West both had their reproductive revolutions last century. Both were engineered to reduce the birthrate but there were significant differences. Western democracies left individuals free to limit their families or not (if “not” then to suffer a certain amount of economic hardship, but still basically free), while China in the early 1980s imposed the one-child policy, with severe penalties, including forced abortions, for disobeying the mandate.
But there’s another, related difference. In China, people continued to marry in their early to mid-20s and almost all abortions were performed to limit family size after the first (or, in some exceptional groups, second) child was born, but in the Anglo-American and European world women were increasingly likely to delay marriage and abort the first and other pre-nuptial pregnancies.
This is important because it is generally accepted that the first full-term pregnancy, especially at a younger age and followed by breastfeeding, protects a woman against breast cancer, for biological reasons that are explained here. Subsequent children and breastfeeding increase this protection.
Initially this gave Chinese women a lower risk of breast cancer than, for example, American women. However, as Huang and colleagues point out, “the incidence of breast cancer in China has increased at an alarming rate over the past two decades” – from around 36 cases per 100,000 women to 51 cases.
Why? One answer could be that multiple abortions eroded the Chinese advantage. The Huang study notes that China has one of the highest prevalences of abortion in the world. An average of 8.2 million medical terminations a year were reported between 1983 and 2010. It is estimated that one in four Chinese women have had at least one abortion, and around 40 pregnancies are aborted for every 100 births.
Could these two things really be unrelated, as the Western breast cancer establishment maintains?
Even Chinese researchers with the government breathing down their necks and still insisting on strict birth control (despite piecemeal relaxations) are not prepared to bury their heads in the sand like that.
Challenging the one-child policy
Five years ago Lei Fan and colleagues at university hospitals in Shanghai published a study of the city’s epidemic of breast cancer and warned of a mounting wave of the disease among cohorts of women whose reproductive years occurred during the past three decades. After noting common risk factors they commented:
We speculate that fundamental changes in reproductive patterns brought about by China’s one-child policy probably contributed most to the incidence boom in the middle-age group. The birth control policy, introduced into Shanghai in 1974 [several years earlier than the national policy] resulted in a fall in birth rates particular[ly] in early fertility. The one-child rate in Shanghai increased to 90.5% in 1978 and this status has maintained at a high level the following years. … Total fertility rate has remained the lowest in the world, at 0.81 in 2006 … When birth cohorts are considered, post-1950 cohorts would be involved in birth-control policy and they are also the cohorts related to the incidence boom. This observed trend supports the hypothesis that the alteration of reproductive factors by birth control policy exerts its effect on the middle-age group.
After this daring assertion it must have been easier for Huang and colleagues to take the next step and address the most likely link between the one-child policy and the explosion of breast cancer among Chinese women.
As far back as 1957 a Japanese study had shown a link between induced abortion and breast cancer and there have been dozens of studies, including Chinese studies, with similar results since. In 1996 US biology professor and endocrinologist Joel Brind and colleagues reviewed the strongest of these and found a 30 percent increased risk of breast cancer after abortion. The study was heavily criticised by other experts and allegedly disproved by a 2003 study led by Valerie Beral.
But no-one looking at the twin epidemics of abortion and breast cancer in one-child China could responsibly dismiss the possibility that one contributed to the other. “As one of the countries with the highest prevalence of IA [induced abortion], in China, it is particularly important to clarify the association between IA and breast cancer risk,” write Huang and co-authors.
The sobering findings of their meta-analysis so far appears to have met with silence from the international research community. Perhaps their reactions are still coming. Dr Susan Gapstur, vice president of the American Cancer Society, has ventured a stock criticism, pointing out that all but two of the 36 studies reviewed used the case-control method, which is subject to response bias. The study addresses this issue and provides a credible explanation of why it would have a minimal effect on their results.
It also explains why two high-profile studies of Shanghai (included in their review) did not show abortion as a significant risk: basically, as Dr Brind has pointed out, when the prevalence of abortion is as high as in that city it is impossible to get a healthy comparison group of typical unaborted women.
In any case, if Chinese scientists wanted to churn out a second-rate study just to burnish their CVs they could certainly have chosen a less politically sensitive subject. Would they risk censure just to give anti-abortionists ammunition?
Furthermore, if the “safe abortion” brigade want to pick holes in the Huang study, they also have to contend with two other Asian studies published last year and reporting mind-boggling figures.
A study from Southern India published in the Indian Journal of Community Medicine in May found a 6-fold greater risk of breast cancer among Indian women with a history of induced abortion compared to women with no history of abortion. In a similar study from Bangladesh published in the Journal of the Dakha Medical College in April increased risk from abortion was even higher – 20 times that of women with no abortions. That’s increases of 2000 percent and 600 percent!
An Asian tsunami
But, as Dr Brind points out, even the much smaller odds found by Huang, when applied to the huge populations of China and India (which together have about one billion women) mean, in the current state of healthcare in those countries, the deaths of millions of women over the coming decade – from the effect of abortion alone. Without adding other risks.
Lei Fan and colleagues have hinted at a veritable tsunami of breast cancer threatening China as wave after wave of women who have been compelled to abort their babies in order to meet the rules of the Chinese fertility revolution grow older.
Women in the prosperous and free countries of the West are under no such compulsion, but they do suffer under a quasi-official rule that withholds from them information about abortion that may be vital to their health and their very lives.
Ironically, it is the totalitarian regime in China that may be setting the standard for freedom of information on this issue. Let’s see what happens next.
Carolyn Moynihan is deputy editor of MercatorNet.