Polycystic ovary syndrome increases the risk of pregnancy complications
Women with polycystic ovary syndrome are more likely to have problems with pregnancy regardless of whether they are undergoing fertility treatment, claims new research published on bmj.com today.
Swedish researchers call for better monitoring of women with polycystic ovary syndrome during pregnancy and giving birth because they are more prone to giving birth prematurely, diabetes and pre-eclampsia – outcomes which are not explained by assisted reproductive technology, as previously thought.
Polycystic ovary syndrome is a common disorder that affects between five and fifteen percent of women of reproductive age.
With the condition, a woman typically has a number of small cysts around the edge of her ovaries and symptoms include irregular periods, problems getting pregnant because affected women either fail to ovulate or they ovulate infrequently, weight gain and excessive hair growth. Women with the condition are more likely to have fertility treatment.
Researchers from Karolinska Institutet and Karolinska University Hospital in Stockholm, Sweden set out to study the risk of adverse pregnancy outcomes in women with polycystic ovary syndrome, taking into account maternal characteristics and fertility treatment.
They studied nationwide data on 3,787 births among women with polycystic ovary syndrome and 1,191,336 births among women without the condition.
They measured risk of adverse pregnancy outcomes, such as diabetes brought on by pregnancy, pre-eclampsia, premature birth, stillbirth, neonatal death, and poor health of newborns, taking into account maternal characteristics (body mass index, age), socioeconomic factors, and fertility treatment such as IVF.
Analysis of the results showed that women diagnosed with polycystic ovary syndrome were more often obese and more commonly used assisted reproductive technology than women without the condition.
There was a strong link between having the syndrome and pre-eclampsia – women with the syndrome were 45 percent more likely to experience pre-eclampsia – and these women were also more than twice as likely to give birth prematurely and/or to develop diabetes while pregnant.
Babies born to mothers with polycystic ovary syndrome were more prone to be large for gestational age and tended to develop asphyxia labour.
Overall, the researchers found that a diagnosis of polycystic ovary syndrome was associated with increased risks of adverse pregnancy outcomes that could not be attributed to the increased use of assisted reproductive technology or maternal characteristics such as advanced age or being overweight or obese.
The researchers conclude: "These women may need increased surveillance during pregnancy and parturition [giving birth]. Future research would benefit from focusing on glucose control, medical treatment and hormonal status among women with polycystic ovary syndrome during pregnancy."
In an accompanying editorial, Professor Nick Macklon from the University of Southampton, says: "It is clear that women with polycystic ovary syndrome should be considered "high risk" obstetric patients and that midwives, general practitioners, and obstetricians should monitor these women as such."
However, he believes that "more evidence is required to support the use of currently used interventions designed to reduce perinatal risk, and this requires a greater understanding of the different polycystic ovary syndrome phenotypes and the underlying mechanisms by which this common condition alters pregnancy outcomes."
Risk of adverse pregnancy outcomes in women with polycystic ovary syndrome: population based cohort study.
BMJ 2011 Oct;343():d6309