The Positive Connection Between Birth Control and Rheumatoid Arthritis

It is not uncommon for women to hear that hormonal contraceptives are harmful to their health, or will negatively affect their fertility. The truth is that like any medication contraceptive pills of course come with their side effects and risks, but the amount of hormones that circulate the body of a pregnant woman are much higher than what is found in a contraceptive pill.

For many years contraceptive pills have been being used as treatments for various conditions. Now research is saying that they may also lower risk of rheumatoid arthritis (RA)!

RA is not something that is well understood, and its causes are generally unknown. This makes it both difficult to prevent and treat. RA affects more women than men annually, and for this reason, hormones have been thought to play a role in RA development. Additionally, RA tends to appear earlier in the life of a woman than it does in a man. Since many autoimmune diseases such as RA, multiple sclerosis (MS), and Lupus, affect women more than men, it is possible that sex hormones such as estrogen, progesterone, and testosterone play a role. Pregnant women who have high levels of these hormones have shown decreases in their RA symptoms. To date however, research looking at the effects of hormones on RA have been rather uninformative in one direction or the other.

What’s the connection between birth control and RA?

Contraceptive pills usually contain low doses of either estrogen and progesterone, or just progesterone. Aside from preventing pregnancy, the benefits of contraceptive pills can be numerous. They can prevent follicular cysts in the ovaries, and be effective in relieving endometriosis related pain and symptoms. They preserve bone density and can also improve asthma symptoms. They are used to treat menstrual migraines and have also been shown to delay MS. Contraceptive pills have successfully been used to treat many disorders in women, so it should be of no surprise when researchers discover their additional benefits.

Recently the Annals of the Rheumatic Diseases published an online article that shows how their research indicates that taking contraceptive pills, especially for 7 or more years could lower the risk of RA development.

The research that was conducted looked at a possible link between RA development and contraceptive pill use, or breastfeeding in women who had at least one child. To gather this information researchers looked at data from the Swedish Epidemiological Investigation of Rheumatoid Arthritis (EIRA). This data included women who were 18 years of age or older, and who lived in a defined area of Sweden between the years of 1996 and 2014.

What kind of results were recovered?

Within this timeframe, they found that 2809 women were diagnosed with RA. They then randomly selected 5312 women who matched in age, from the general population to use as a comparison group. Next they took blood samples from all the people participating to look for antibodies to RA. In depth questioning about contraceptive and reproductive histories as well as lifestyle, education, and breastfeeding history was conducted. After all of this, 2578 women with RA and 4129 women from the general population were used for the final analysis. The results showed that of these women, 8844 with RA, and 1949 from the comparison group breastfed one child or more between 2006 and 2014.

Their results also showed that regardless of the length of time used, women who had used contraceptive pills were at a decreased risk of developing RA when compared to women who had never used contraceptive pills. Additionally, for current contraceptive pill users, their risk is 15 percent lower, and past users have a decreased risk of 13 percent.

Women who tested positive for anti-citrullinated protein antibodies (ACPA) even after after taking into account tobacco and alcohol use, are at high risk for RA development. The study reported that 9 out of 10 people who test positive for ACPA will have RA, and the presence of these antibodies may indicate a more serious disease.

Among the study participants who had used contraceptive pills, the average length of use was more than 7 years. This was associated with a 19 percent lower risk of RA development compared with the control group. Interestingly, this decreased risk held true for people who tested positive, and for people who tested negative for ACPA.

The study also looked at the effect that breastfeeding has on RA development risk. They found that while a lower risk was present among women who had breastfed one child, after other factors were included, this risk decrease was not significant.

It’s still a mystery

As this was an observational study, conclusions about cause and effect cannot be drawn, so the great “hormone effect on RA” mystery remains a mystery. Additionally, researchers were unable to gather data about which contraceptive pills and what dosing the study participants had used throughout their lives. This presents a challenge when trying to develop clinical recommendations using this data.  Luckily, the sample size was large enough to provide a decent representation of the population.

This is not the first research published on the effect of contraceptive pills on RA prevention. In 2013 the International Journal of Endocrinology Metabolism published an article about the non-contraceptive benefits of oral hormonal contraceptives. In this article they note that contraceptive pills have been found to decrease the risk of a patient developing RA by about 30 percent, and by 50 percent in hospital based case studies. They report that the decrease is greatest in women who have used contraceptive pills for 5 years or longer. The authors also note that the evidence does not suggest that contraceptive pills effect long term outcomes of RA once it has already developed.

Hopefully this information sparks more researchers to look into the details of how hormones and RA are related, and how contraceptive pills can be of help. This knowledge could provide a greater understanding of the pathophysiology of the disease and help guide healthcare providers in making clinical decisions. With about 70 different types of contraceptive pills on the market, being able to provide healthcare providers with guidance about which ones may offer patients the most protection from RA could be greatly appreciated.

With all the potential benefits of contraceptive pills, hopefully more accurate information about their use and how they affect the female body will start permeating the internet and social media. If you are currently taking a contraceptive pill, you could have one more thing to thank it for now!