"Your pregnancy history affects your chances of getting breast cancer. If you give birth to your baby, you are less likely to develop breast cancer in the future. Research indicates that having an abortion will not provide you this increased protection against breast cancer."
– information published in "A Woman's Right to Know Information Material" booklet by the Texas Department of Health Services, December 2016
"A Woman's Right to Know" is an informed-consent booklet for pregnant women, mandated by a 2003 state law in Texas. The Texas Department of Health Services published a revised version of this booklet in 2016, replacing the one that had been used since 2003.
A reader pointed us to this blurb, included under the heading "Breast Cancer Risk," in a section about the risks of getting an abortion. According to this booklet, there is research showing that having an abortion "will not provide" women the "increased protection against breast cancer." What does the research say?
Correlation may not prove causation
The theory that abortion is associated with a greater risk of breast cancer dates to the 1950s. It was widely promoted in the wake of the 1973 Roe v. Wade decision, and was dubbed the "ABC Link" (Abortion/Breast Cancer Link).
In the 1990s, several case-control studies supporting this link were published. Case-control studies are used to determine whether a certain risk factor is associated with a disease or medical condition. It takes a group of people who have the medical condition ("case"), and another group of people who are similar in age and gender but don't have that condition ("control"), and tries to find a variable that led to the medical condition.
So these studies found that there were more women who had breast cancer ("case") who had an abortion, compared to women who didn't have breast cancer ("control"). But other researchers disputed this method, and questioned whether this correlation proved causation.
In 2003, the National Cancer Institute held a workshop of more than 100 experts from around the world to determine whether this link truly exists. These experts found that studies confirming the ABC Link were poorly designed, often involved a small group of women and relied on self-reporting by women rather than their medical records.
Newer studies of larger groups of women, which used medical data before and after breast cancer was found, consistently showed no association between induced abortion (which excludes stillbirth and miscarriages) and breast cancer risk, according to the report from the 2003 workshop. One researcher submitted a minority dissent report claiming partial disagreement with this conclusion.
The American College of Obstetricians and Gynecologists Committee on Gynecologic Practice concluded in 2009: "Early studies of the relationship between prior induced abortion and breast cancer risk were methodologically flawed. More rigorous recent studies demonstrate no causal relationship between induced abortion and a subsequent increase in breast cancer risk."
The Texas booklet doesn't outwardly claim that research supports the ABC Link, but the wording misleads the reader to come to a similar conclusion.
Pregnancy and breast cancer
Research generally backs up the first two sentences: "Your pregnancy history affects your chances of getting breast cancer. If you give birth to your baby, you are less likely to develop breast cancer in the future." There are many risk factors for breast cancer, including ones that relate to a woman's pregnancy history. (Breast-feeding and exercise are also associated with decreased risk of breast cancer.)
In particular, women who deliver their first baby to full-term at 30 years or younger face a decreased long-term risk of breast cancer than women who have their first baby at older than 30 or 35, or who never deliver a baby at all.
Women who deliver a baby before they are 20 years old face a 50 percent decreased risk of breast cancer than women who don't give birth or give birth after 35 years old, according to the National Cancer Institute.
A 2016 study by the International Society of Oncology and Biomarkers described it this way: The longer it takes between your first menstrual period and your first pregnancy, the greater risk you face of getting breast cancer. And part of the reason that more women have breast cancer now is that girls are getting their periods earlier (because they have more protein and fat in their diets), and women are having babies later (because they are working and delaying childbirth). Those women who are delaying childbirth also may have had abortions.
Wording ‘technically correct’ but ‘deceiving’
The next claim in the booklet is misleading: "Research indicates that having an abortion will not provide you this increased protection against breast cancer." Having a baby does provide increased protection against breast cancer, but it doesn't mean that having an abortion affects your risk one way or another.
"The wording in Texas [booklet] gets very cute," said Otis Brawley, chief medical officer at the American Cancer Society. "It's technically correct, but it is deceiving."
For example, women who deliver a child before 30, but then have an abortion after their first child, still have a decreased risk of breast cancer, said Brawley, who described himself as "pro-life and pro-truth."
The Texas Department of Health Studies pointed us to five studies in the footnotes of the booklet. Two of the studies say there is no significant association between abortions and the risk of breast cancer.
A third study found that women in India who have a non-vegetarian diet or had more years of education faced a greater risk of breast cancer. Educated women are more aware of detecting breast cancer, or are married later and have their first children later in life (possibly having abortions to delay childbirth), the study says.
The final two studies reported associations between induced abortions and women with breast cancer in China, and using the disputed case-control method to prove this association.
"The booklet reports on the risk reduction associated with carrying a baby to term and generally notes ongoing breast cancer research," said Carrie Williams, chief press officer for the Texas Health and Human Services Commission. "We reviewed many types of studies and numerous medical resources, including information from the American Congress of Obstetricians and Gynecologists, Royal College of Obstetricians and Gynaecologists, medical embryology texts and governmental health and medical resources."
Williams did not comment on the disputed methodology.
Misleading information
This booklet lists "Breast Cancer Risk" as one of the risks of abortion, and claims that abortion "will not provide" a woman with "this increased protection against breast cancer." It is easy to glance over this section and come away with an impression that getting an abortion could put a woman at more risk of getting breast cancer.
But research overwhelmingly shows that abortion is not associated with a woman's risk of getting breast cancer. Further, the citations in this booklet point to research from a disputed methodology to find such an association, or cite studies that explicitly say there is no association between abortion and protection against breast cancer.
The use of technically correct but misleading language give this a rating of untrue.
But this section in the booklet doesn't tell the women how much her risk of getting breast cancer can be affected by how old she is when she delivers her first baby. Instead, it makes it seem as though getting an abortion is the deciding risk factor. Further, this is a government report that purports to give a woman all the information she needs to know about her pregnancy, yet cherry-picks information to create a misleading impression.