Women with premature ovarian insufficiency, whose periods stop before 40, have a much greater risk of severe autoimmune diseases, according to research.
Premature ovarian insufficiency (POI) occurs when women under 40 no longer produce eggs because their ovaries have stopped working properly. Periods become irregular and then stop, and some women experience menopause symptoms. It affects 1% of women globally.
A study has found that women with POI are twice to three times as likely to develop severe autoimmune conditions such as type 1 diabetes, overactive thyroid, lupus and inflammatory bowel disease, compared with the general population.
The researchers say the findings significantly strengthen the hypothesis that autoimmune processes play a “pivotal role” in the onset of POI.
The study, published in Human Reproduction, is the largest to investigate the link between autoimmune conditions and POI.
Finnish academics followed almost 20,000 women for at least 12 years. They analysed health data from Finland’s comprehensive registries and identified almost 4,000 women under 40 with a POI diagnosis between 1988 and 2017.
Each was matched with four women of similar ages. They then studied how many developed severe autoimmune conditions between 1970 and 2017. They found that 5.6% of women with POI had been diagnosed with at least one autoimmune disorder before their diagnosis and 12.7% after diagnosis with POI.
Overall, women were 2.6 times more likely to have an autoimmune disease before a POI diagnosis when compared with the control group. These risks varied from nearly double for overactive thyroid glands and rheumatoid arthritis to nearly 26 times for polyglandular autoimmune diseases.
Women with POI who did not have a pre-existing autoimmune condition were nearly three times as likely to be diagnosed with one in the following three years.
These links are likely to be an underestimation, the authors say, because the study only included autoimmune disorders diagnosed in specialist health centres: less severe conditions such as coeliac disease and underactive thyroid glands are often diagnosed and treated in primary healthcare, so the overall prevalence of autoimmune disorders in women with POI is higher.
Dr Susanna Savukoski, a gynaecology and obstetrics doctor at Oulu university hospital and the University of Oulu, Finland, who led the study, said: “It is important to stress that most women with POI do not develop severe autoimmune conditions, and most women with severe autoimmune diseases do not develop POI. However, medical professionals should be aware of the increased risk, and patients should be informed about it as well.”
As POI threatens fertility, women with an increased risk of the condition should consider trying to conceive when they are young, she says, although some autoimmune diseases can significantly increase the risk of pregnancy complications and should be considered.
The authors want to study the biological mechanisms of POI and autoimmune diseases to help the development of preventive treatments. Savukoski said: “We are investigating whether long-term use of [hormone replacement therapy] can prevent other conditions developing among women with POI.”
Responding to the findings, Louise Kenny, a professor of maternal and foetal health at the University of Liverpool, said: “POI is poorly understood and devastating. It limits the possibility of young women carrying their own biological child as well as increasing their risk of menopausal-related complications such as osteoporosis.”
New research was needed to confirm the role of the immune system, she added.
Bassel Wattar, an associate professor of reproductive medicine at Anglia Ruskin University, said the research highlighted the need for multidisciplinary and holistic care for women with POI due to the increased risk of long-term health complications.
He added: “This study does not help us to understand the causality of POI and therefore it remains to be answered if it is a consequence of autoimmune disorders or if the lack of ovarian activity can exaggerate an autoimmune response among affected women.”
