Women diagnosed with polycystic ovary syndrome (PCOS), an endocrine disorder that can cause fertility problems, are more likely to have parents with heart disease, hypertension or a stroke, a new study has found.
Between 8% and 18% of women have PCOS, but many do not realise it until they encounter problems trying to conceive. Symptoms vary but can include irregular periods, tiny ovarian cysts, diabetes-like insulin resistance and weight problems. PCOS patients may also have an increased risk of diabetes, cardiovascular disease, obesity, depression and anxiety but the causes of the disorder have baffled experts for years.
A new study of 700 women by researchers at the University of Adelaide, published today in the journal PLOS One, found that mothers of women with PCOS are more likely to have cardiovascular disease and almost twice as likely to have high blood pressure, than mothers of other women.
Fathers of women with PCOS are more than twice as likely to have heart disease, and more than four times as likely to have a stroke, than fathers of other women, the study found.
“It may be due to several factors. It could be that there’s a common genetic pathway that possibly operates on placental function,” said the lead author of the study, Associate Professor Michael Davies from the University of Adelaide’s Robinson Institute.
“It could be that mothers who are going to progress to heart disease or hypertension have subtle variations in placental function that induces metabolic programming in the offspring and we are seeing the reproductive consequences of that.”
The link between fathers with higher stroke risk and daughters with PCOS was particularly intriguing, Associate Professor Davies said.
“It begs the question as to whether there a direct paternal genetic effect on the female fetus or a paternal gene that is expressed in the placenta to alter placental function,” he said.
Lifestyle factors that contribute to a father’s stroke risk, like smoking or obesity may also somehow alter growth and development of his daughter in utero, with reproductive consequences, said Dr Davies.
The study drew on the family medical histories of 700 women women born at Adelaide’s Queen Elizabeth Hospital between 1973 and 1975.
A better understanding of the link between family medical history and PCOS may lead to earlier diagnosis and better treatments, but more research was needed, Dr Davies said.
“This study shows there’s benefit to be had for doing family-based studies, relating symptom clusters back to family histories.”
Knowing that there is a link between PCOS and parental health could also serve as a warning bell for mothers and fathers of young PCOS sufferers, said Professor William Ledger, a PCOS expert and Head of Obstetrics and Gynaecology the University of NSW.
“We have known about PCOS for many years as a gynaecological problem but over the last 10 or 15 years we have begun to realise the metabolic problems that go along with it,” said Dr Ledger, who was not involved in the study.
“It is the first time that this kind of family study has been done. It may help raise awareness among the parents of women with PCOS that they need to get their own health checked out.”
However, Professor Roger Hart, an expert in reproductive medicine from the University of Western Australia said it was not surprising there familial link.
“We know that women with PCOS have a higher risk of cardiovascular disease and diabetes and that there is a familial link for PCOS,” he said.
“If a mother has features of PCOS her daughter is likely to express some of those features.”
The finding showed that people in families with a history of PCOS should adopt a healthy lifestyle to mitigate against their increased chance of cardiovascular disease, he said.