Explainer: Why pregnancy is not a treatment for endometriosis
|Let's kick this myth to the curb!|
Is there any scientific evidence that pregnancy reduces endometriosis disease and/or symptoms?
In a nutshell: No.
Several papers published in medical journals have made this claim without reference to a scientific study (which is typically required when making any claim in a medical journal). On the rare occasion that a reference is provided it is usually to the study by Moen & Muus published in 1991.
Moen & Muus compared 16 women who were pregnant and had endometriosis to 24 women who were not pregnant and had endometriosis. Both groups of women underwent tubal sterilization (they had their ‘tubes tied’); the women who were pregnant were also having their pregnancy terminated during the surgery.
It was noted that the women who were pregnant at the time of surgery appeared to have less severe looking endometriosis disease compared to those who were not pregnant. And this is why some people use this study as evidence that pregnancy can 'treat' endometriosis. But there is more to the story!
There are many limitations to this study not to mention alternative explanations for the findings. At the conclusion of their paper, the authors highlight three important things to consider:
- The women who were pregnant had been so for less than 12 weeks; it is unlikely that this is enough time for the pregnancy to have an effect on the disease.
- It is more likely that the women who were pregnant had less physically severe endometriosis in the first place (prior to their pregnancy).
- Alternatively, it cannot be excluded that being pregnant actually caused the early stage endometriosis observed in this group of women!
Some people have also argued that while there is no evidence, there is a strong theoretical argument that pregnancy could reduce endometriosis disease and symptoms. This argument is usually based on the idea that progesterone (a type of hormone) is thought to reduce and prevent the growth of endometriosis disease. Progesterone levels are higher during pregnancy and therefore potential benefits may be experienced at this time.
However, there is just as strong a theoretical argument that pregnancy could make endometriosis disease and symptoms worse. Estrogen (a different type of hormone) is thought to increase endometriosis disease growth. Estrogen levels are also high during pregnancy, and therefore the disease and symptoms may become worse during this time.
Another factor to consider is the rapid growth of the uterus during pregnancy which may increase women’s symptoms by pulling and stretching scar tissue and disease. Further, there is increasing evidence that having a cesarean section may increase endometriosis disease and symptoms.
So why do doctors keep telling me I should get pregnant?
Throughout much of history there has been a strong belief that the purpose of women and their bodies is to be mothers and to reproduce. This belief remains popular today despite many women (and some men) challenging it.
Being human, doctors are very much part of their culture. It may be difficult for them to identify socially constructed beliefs that are part of their everyday world when they are providing health care. This may be more difficult when providing care to someone with a condition that has little research evidence (as is the case with endometriosis) as the lack of evidence may prompt them to resort to other sources of knowledge.
While it is not wrong to consider options that are not yet supported by research evidence, such options must be judged by their benefit to patients. Further, patients have a right to know what their doctor's recommendations are based on. Given the physical, emotional and financial burden of pregnancy, it is inappropriate and potentially harmful to recommend it to women as ‘treatment’.
Image: Death to the Stock Photo