AimTo assess the impact of intermittent fasting, with or without probiotic supplementation, versus a calorie‐restricted diet on anthropometric measures, metabolic status and gonadal variables in women with polycystic ovary syndrome (PCOS).MethodsThis is a randomized, placebo‐controlled, parallel‐arm clinical trial. The effects of the 14:10 early time‐restricted eating (eTRE) strategy alone or combined with probiotics, on obese women with PCOS, were investigated. Participants were divided into three groups: eTRE plus probiotics (n = 30), eTRE plus placebo (n = 30) and a control group following a standard three‐meal‐per‐day diet with daily calorie restriction (DCR) (n = 30). Over 8 weeks, various anthropometric, metabolic, menstrual and gonadal variables were assessed.ResultsA total of 90 individuals were included in the study, with a mean body weight of 81.4 kg, and a mean age of 30 years. Mean (standard deviation) weight loss was not different between the groups at week 8 (TRE + probiotic: −2.2 [1.6] kg vs. TRE + placebo: −2.9 [2.7] kg vs. DCR: −2.5 [1.7] kg). Results revealed that, while all three regimes led to reductions in body weight, body mass index, vascular risk indicators, hirsutism and acne scores, there were no statistically significant differences between the eTRE groups and the control group in terms of weight loss, or improvements in metabolic, menstrual and gonadal variables (P > .05). Additionally, combining probiotics with eTRE did not benefit hormonal and cardiometabolic factors (P > .05).ConclusionsThe eTRE alone or eTRE plus probiotics did not result in significantly greater weight loss or improvements in metabolic, menstrual and gonadal variables compared with the standard three‐meal DCR diet.