Dr Rima Dhillon-Smith received her undergraduate medical training from the University of Birmingham (2009), and completed her core training in Obstetrics and Gynaecology, as well as subspecialist training in reproductive medicine and surgery in December 2023. Rima was awarded her PhD, titled “Risk stratification for women undergoing in-vitro fertilisation” in 2015 and achieved multiple high-impact publications from this work. 

She was the lead investigator and first author on the TABLET (Thyroid Antibodies and LEvoThyroxine) trial (£1.7million NIHR EME funded) in the New England Journal of Medicine. She is internationally known for her work in thyroid disease and fertility and pregnancy. She is a co-author on multiple international guidelines (RCOG and ATA). Furthermore, she is part of a collaboration with the Consortium of Thyroid and Pregnancy and has submitted national grant applications for projects within the collaboration.

Rima is a senior investigator for the LOCI trial, a multi-centre £2.1million NIHR HTA funded project investigating Letrozole vs Clomifene (with or without metformin) for ovulation induction in women with PCOS.

Rima has been awarded grants from the Academy of Medical Sciences and NIHR for her work in thyroid disease

Rima’s research spans reproductive endocrinology, assisted reproduction, miscarriage and early pregnancy, and paediatric and adolescent gynaecology. Her methodological expertise includes clinical trials, individual participant data and aggregate-data meta-analysis, prediction modelling and prospective cohort studies.

Reproductive endocrinology

Rima is internationally recognised for her research into thyroid disease before and during pregnancy. She was the lead clinical research fellow for the NIHR-funded TABLET trial and first author of its primary report in the New England Journal of Medicine. She subsequently led an NIHR-funded individual participant data meta-analysis evaluating levothyroxine treatment in women with mild thyroid dysfunction before conception and during pregnancy.

Her work has contributed to multiple national and international clinical guidelines. She is an author of the 2026 American Thyroid Association Guidelines for Thyroid Disease in Preconception, Pregnancy and Postpartum; the 2025 RCOG Green-top Guideline on the Management of Thyroid Disorders in Pregnancy; and the 2025 Society for Endocrinology Clinical Practice Guideline for the Evaluation of Androgen Excess in Women.

Rima is also a senior investigator for the NIHR-funded LOCI trial, which is evaluating letrozole and clomifene, with or without metformin, for ovulation induction in women with polycystic ovary syndrome (PCOS). Her wider work in PCOS includes research into metformin use before conception and during early pregnancy.

Rima has led competitively funded research supported by the NIHR, the Academy of Medical Sciences, the NIHR Birmingham Biomedical Research Centre, charitable organisations and industry partners.

Assisted reproduction and subfertility

Rima’s research aims to improve the effectiveness, safety and personalisation of fertility treatment. Her work includes large multicentre studies of luteal-phase support, ovarian response, fertility-treatment add-ons and embryo selection, including the use of prediction models and machine-learning methods. Rima also supervises doctoral researchers undertaking studies in collaboration with Care Fertility.

Early pregnancy and miscarriage

Rima is Lead for the Birmingham Tommy’s National Centre for Miscarriage Research and a co-applicant on the £2.5 million national centre programme. She leads and contributes to research investigating the causes, prediction, prevention and treatment of miscarriage.

Rima is a Chief investigator of PREMIS (Preventing Miscarriage through Platform Testing of Multiple Interventions), a national prospective cohort and trial platform designed to evaluate multiple interventions for preventing miscarriage efficiently. The platform includes embedded randomised trials and provides an infrastructure for studying the biological, clinical and lifestyle factors associated with pregnancy outcomes.

Rima supervises several doctoral researchers working across miscarriage epidemiology, mechanisms and intervention development.

Paediatric and adolescent gynaecology

Rima has completed advanced RCOG training in paediatric and adolescent gynaecology. Her clinical and research interests include heavy menstrual bleeding, menstrual pain, premenstrual symptoms and PMOS in children and young people. She co-authored the British guideline on heavy menstrual bleeding in adolescents and is developing and evaluating new interventions for adolescent menstrual disorders.

Research groups, centres and professional networks

• Lead, Birmingham Tommy’s National Centre for Miscarriage Research
• Co-lead, Women’s Metabolic Health, NIHR Birmingham Biomedical Research Centre
• Deputy Theme Lead, Maternal and Reproductive Health, University of Birmingham
• Committee member, International Consortium on Thyroid and Pregnancy
• Deputy Lead, British Fertility Society Research and Innovation Special Interest Group
• Basic and Clinical Science Officer, ESHRE Reproductive Endocrinology Special Interest Group

• Member of Royal College of Obstetricians and Gynaecologists (2017)
• PhD – University of Birmingham (2015)
• MBChB – University of Birmingham (2009)