Background: Polycystic ovary syndrome (PCOS) is a common endocrine condition which affects women in the reproductive age group. South Asian women with PCOS have a higher risk of insulin resistance and metabolic disorder compared to women from other ethnic backgrounds. Lifestyle interventions such as dietary advice and physical exercise are recommended as a first-line management option for infertile women with PCOS. Most of the randomized controlled trials evaluating the role of lifestyle interventions in infertile PCOS women were characterized by methodological issues. The uptake of lifestyle modifications as a treatment strategy in the South Asian population is complicated by a difficult-to-change conventional high-carbohydrate diet and limited availability of space for physical activity in the region., Methods: The study is designed as an open-label, multicentre, randomized controlled trial in South Asian women with PCOS. Women attending the fertility clinic will be screened for eligibility, and women aged between 19 and 37 years who have been diagnosed with PCOS and wishing to conceive will be invited to participate in the trial. We will include women with body mass index (BMI) between ≥ 23 and ≤ 35 kg/m 2 and duration of infertility ≤ 3 years. We plan to randomize women with PCOS into two groups: group A will receive the intervention which will consist of individualized advice on diet and physical exercise along with a telephonic reminder system and follow-up visits, and group B (control) will receive one-time advice on diet and physical exercise. Both groups will receive up to three cycles of ovulation induction with letrozole after 3 months of randomization during the 6-month treatment period. The primary outcome of the trial will be the live birth following conception during the intervention period. The secondary outcomes include clinical pregnancy rate, ongoing pregnancy rate, miscarriage rate, ectopic pregnancy rate, stillbirth, time to pregnancy, mean weight loss, differences in anthropometric parameters, improvement in menstrual regularity and quality of life score., Discussion: The IPOS trial results could help clarify and provide more robust evidence for advocating an individualized lifestyle intervention in PCOS women who wish to conceive., Trial Registration: Clinical Trial Registry of India CTRI/2023/04/051620. Registered on 13 April 2023., (© 2023. The Author(s).)