Contraceptive Pill and Asthma

Introduction

Asthma is a chronic respiratory disease that is mainly characterised by inflammation of the airways and shortness of breath. It is a common condition affecting over 300 million people worldwide^[8]. While asthma is more prevalent in those assigned male at birth than in prepubertal (before puberty) people assigned female at birth (PAFAB), it becomes more severe in those assigned female during puberty. This difference may be due to female sex hormones and the hormonal changes that occur in PAFAB, such as during the menstruation cycle, pregnancy and menopause. 

Contraceptive pills are used mainly by PAFAB to prevent pregnancy. The “pill” is the most common form of contraception, with three main types of oral contraceptives; combined estrogen-progesterone, progesterone-only, and continuous/extended use pill^[3]. Several studies have found an association between the use of oral contraceptive pills and asthmatic symptoms^[1].

Asthma and hormones

Asthma is mainly characterised by the inflammation and narrowing of the small airways in the lungs and is heavily affected by other factors, including the environment, stress levels in the body and hormone production.

Hormones play an essential role in carrying messages in the bloodstream that ensure proper communication between different organs and tissues. They work slowly and affect various processes such as mood, growth, development, metabolism and sexual functions. Sex hormones play a crucial role in both reproductive and non-reproductive processes. In PAFAB, the two main sex hormones produced are estrogen and progesterone. These hormones are mainly created in the ovaries, adrenal glands and the placenta during pregnancy. They influence weight, bone, muscle and hair growth, and sex organ development.

Before the beginning of someone’s menstrual cycle, there is a decrease in estrogen and progesterone levels. This influences the severity of asthma symptoms. ^[5] However, it is important to note that the worsening effect that occurs is due to the fluctuation of hormone levels rather than a decrease in them. One possible reason is that this hormonal fluctuation can activate proteins that trigger an inflammatory response, which in turn aggravates asthmatic symptoms. 

Furthermore, estrogen possesses pro-inflammatory functions which in some cases can lead to an increase in asthma symptoms during periods of hormonal imbalance, such as when one uses contraceptive pills. Therefore, the research suggests that both naturally produced estrogen by PAFAB and external estrogen that is acquired from hormonal contraceptives can impact asthma.

Can I take contraceptive pills if I have asthma?

Contraceptive pills are used to prevent pregnancies and, in some cases, to regulate hormonal imbalances in women. Oral contraceptives, both the combined pill and the progesterone-only pill, are safe to be taken by asthmatic patients.

While in some cases hormonal contraceptive pills can lead to an exacerbation of symptoms, in other cases it has been found to provide relief. However, as of yet, contraceptive pills have not been found to present an imminent risk to the health of PAFAB who are asthmatic ^[9]. 

Different forms of birth control also can have different effects on PAFAB. For instance, the “morning after” pill, also known as emergency contraception, is not recommended for asthmatic PAFAB. In fact, due to the synthetic or man-made progesterone that it contains, it could worsen asthma symptoms ^[4]. 

However, it is best to talk to a GP before taking any form of birth control pill in order to ensure safe sexual health, proper management of your asthma and decrease your risk of developing potentially dangerous side effects. Consultations can be done in an assessment clinic, online, or by an appointment, usually by a nurse. 

Does the contraceptive pill lower my chance of developing Asthma?

While there is no definitive answer as to whether birth control lowers the chances of developing asthma, many studies indicate that oral contraceptives can help alleviate asthmatic symptoms. A large study conducted over 17 years found that hormonal contraceptives reduce asthma severity in women of reproductive age as it reduces fluctuations in the levels of sex hormones, thereby reducing the chance of experiencing worse asthma symptoms ^[6]. Some women have reported that exogenous sex hormones in birth control pills help alleviate these symptoms. On the other hand, several different studies have also shown that hormonal contraceptive pills play a role in the exacerbation of asthma in PAFAB. The reasons behind both contradictory conclusions are still not clear, but it is believed that this may be caused by different genetic predispositions and environmental factors ^[2]. Nonetheless, it is important to note that asthma is a multifactorial disease. With that being said, there are no studies currently that show the ability of the contraceptive pill to lower the chances of developing asthma; only to alleviate symptoms. 

Future Research

Several ongoing studies are being conducted to gain a clearer understanding of the link between contraceptive pills and asthma. This will allow medical professionals and those with asthma to manage this condition more efficiently, all while also ensuring good sexual healthcare. 

Summary

To summarise, asthma is a prevalent respiratory condition that is influenced by several factors, including hormonal changes. Contraceptive pills are one of the main modes of birth control used by women and they work by regulating female sex hormones. Over the past few years, a link between hormonal contraceptive pills and asthma has been established. Some studies have found oral contraceptive pills to be beneficial in the decrease of asthma symptoms, while others have found that they worsen symptoms. Despite this clear link, it is still not definitively clear whether contraceptive pills play a positive or a negative role in asthma ^[7].