Desogestrel Linked to Increased Breast Cancer Risk, Major Swedish Study Finds
A new, extensive study involving over two million women suggests a link between the use of the progestogen desogestrel and a higher risk of breast cancer, prompting a reassessment of hormonal contraceptive options.
Hundreds of thousands of women in Sweden rely on hormonal contraceptives annually, and the landscape of available products has evolved significantly over time. From traditional combined pills containing both estrogen and progestin to progestin-only methods like minipills, hormonal IUDs, implants, and injections, the choices are numerous.While previous research largely centered on combined oral contraceptives, the increasing popularity of progestogen-based alternatives necessitates a deeper understanding of their long-term health implications. The complexity is further compounded by the variety of progestogens used, each with differing strengths and potential effects on cancer risk.
The groundbreaking study,published recently,is the largest of its kind to date. Researchers leveraged Sweden’s unique national register – a comprehensive database of prescriptions and cancer diagnoses – to analyze the health outcomes of over two million women aged 13-49 between 2006 and 2019. The goal was to identify potential risks associated with different types of contraceptives.
“Not all hormonal contraceptives have the same effect on the risk of breast cancer,” explained a senior researcher involved in the study.”Our results indicate that some progestogens – especially desogestrel – are linked to a higher risk of breast cancer, while others, such as injections with depot medroxyprogesterone acetate, did not show any increase.”
The research also revealed that combined birth control pills and hormonal IUDs containing levonorgestrel, both commonly used in Sweden, were associated with a lower risk of breast cancer compared to desogestrel.
any use of hormonal birth control was linked to a 24 percent increased risk of breast cancer, translating to approximately one additional cancer case per 7,800 users annually. This risk escalated with prolonged use. Long-term use – defined as 5-10 years – of desogestrel products correlated with an almost 50 percent higher risk, while comparable use of levonorgestrel products showed a slightly under 20 percent increase. Notably, birth control pills containing drospirenone combined with estrogen, also prevalent in sweden, did not demonstrate any increased risk. These may represent a safer option for women with pre-existing risk factors.
“Hormonal contraceptives are very effective and provide important health benefits, and we do not encourage women to stop using them,” emphasized a lead researcher. “In addition to preventing unwanted pregnancies, they reduce the risk of ovarian and endometrial cancer, relieve menstrual pain and heavy bleeding, help with acne, and give women greater control over their reproductive health.” however, given that breast cancer remains the most common cancer among women, the researchers argue that minimizing exposure to perhaps harmful drugs is crucial, particularly for those already at risk.
Why: Researchers sought to understand the varying effects of different progestogens on breast cancer risk,as previous studies focused primarily on combined oral contraceptives.
Who: The study was conducted by researchers at the Department of Immunology, genetics and Pathology, analyzing data from over two million Swedish women aged 13-49.
What: The study found a link between desogestrel use and an increased risk of breast cancer, while levonorgestrel and drospirenone-containing contraceptives showed lower or no increased risk. Overall hormonal birth control