In a new study published in the Journal of Affective Disorders, researchers discovered that women currently using birth control pills show a lower prevalence of major depression compared to those who have stopped using them.
The birth control pill has been a pivotal element in women’s health for decades, used not only for preventing pregnancies but also for managing menstrual symptoms. Despite its widespread use, there has been ongoing debate and concern regarding its potential impact on mental health, particularly depression.
Previous studies have shown mixed results – some suggesting a link to depressive symptoms, while others indicate no significant effects or even improved mood states in women using these pills. This inconsistency in findings led researchers to delve deeper into the subject, aiming to provide a clearer picture of how birth control pills might affect mental well-being.
“Contraception is a crucial component of preventive health care,” said study author Julia Gawronska, a postdoctoral research fellow at Anglia Ruskin University. “There is no clear evidence linking the pill with depression. However, there is a common misconception that the oral contraceptive pill causes depression. Women who worry about depression and choose not to use effective contraceptive methods put themselves at risk of unintended pregnancies. Promotion of family planning is essential to securing the wellbeing and autonomy of women.”
The study analyzed data from the National Health and Nutrition Examination Survey (NHANES), a program designed to assess the health and nutritional status of adults and children in the United States. It focuses on a representative sample of the population through interviews and physical examinations. The specific data for this study came from women aged 18 to 55 who were part of the NHANES cohorts from 2005 to 2012. This timeframe was selected due to the availability of both depression questionnaires and reproductive health data within the survey. After applying certain criteria to ensure the relevance of the participants to the study’s aims, the final sample size comprised 6,239 women.
The primary area of interest was the current use of birth control pills, including both the combined pill (containing estrogen and progesterone) and the progestogen-only pill. However, the survey data did not differentiate between these two types. Women were categorized based on their responses to questions regarding their use of birth control pills – as current users, former users, or never users.
Depression was assessed using a validated questionnaire, the Patient Health Questionnaire, which is based on the criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders. It helps identify the frequency and severity of depressive symptoms over the previous two weeks.
The study also considered a range of potential influencing factors or confounders, including socio-demographic characteristics (like age, race, income, and marital status), behavioral factors (such as smoking and body mass index), and chronic health conditions (including diabetes, cancer, cardiovascular disease, and thyroid problems).
Women who were currently using birth control pills showed a lower prevalence of major depression (4.6%) compared to those who had never used them (10%) and those who had stopped using them (11.4%).
However, when the researchers examined the data more closely, they found no significant difference in depression rates between current pill users and those who had never used them. Additionally, the study did not find a significant difference between former users and never users. This nuanced finding suggests that while current use of birth control pills is associated with a lower reported rate of depression, the relationship is not straightforward.
“We believe that this could be due to the fact that taking the pill can remove concerns about unwanted pregnancy, therefore helping to improve the mental health of oral contraceptive pill users,” Gawronska told PsyPost. “It is also possible that the results could be influenced by ‘survivor bias,’ where women who experience signs of depression while using oral contraceptive pills stop taking it, moving them into the category of former users.”
“However, stopping taking the pill without a suitable alternative increases the risk of unintended pregnancy. It is important that women are fully supported, provided with full information, and offered alternative forms of contraception if necessary. Based on our findings, women should be aware of potential side effect of depression. However, women should feel comfortable knowing that there are alternative options available.”
The study also found disparities in the prevalence of major depression based on race, marital status, income, smoking status, and chronic health conditions. For instance, black and Hispanic women, those with lower income, and smokers were more likely to report major depression.
But the cross-sectional nature of the survey data means that it captures a snapshot in time, making it challenging to establish cause-and-effect relationships. Another limitation is the lack of detailed data on the specific types of birth control pills used by the participants. The combined pill and the progestogen-only pill may have different impacts on mood, but this study could not differentiate between them.
Given these constraints, the researchers recommend future studies that can more precisely track the onset and progression of depressive symptoms in relation to the use of different types of birth control pills. Such longitudinal studies would help in understanding whether the onset of depression is influenced by the use of these pills or other external factors.
“The prevalence of major depression among women taking oral contraceptive may be lower than in former users of the pill,” Gawronska said. “However, there are some women who still experience clinically relevant depression. Further research with longitudinal follow-up for depression in women using oral contraceptive pills is needed to understand the real world effect of the pill on depression.”
The study, “Association of oral contraceptive pill use and depression among US women“, was authored by Julia Gawronska, Catherine Meads, Lee Smith, Chao Cao, Nan Wang, and Susan Walker.