New research suggests that women with polycystic ovary syndrome (PCOS) have lower levels of a specific gut microbe, potentially impacting their fertility. PCOS is the most common hormonal condition in women of reproductive age in the UK and is a leading cause of infertility. Despite its prevalence, little is known about its causes or how to treat it effectively. The study monitored 220 women across 44 cities in China, half of whom had PCOS. It found that those with PCOS had around half the amount of a gut bacteria called Parabacteroides Merdae, which is vital for converting a nutrient present in the gut into healthy short-chain fatty acids beneficial for reproductive health. However, some medical professionals remain sceptical about this potential correlation and insist on further research.