Glucose concentrations within target, appropriate gestational weight gain, adequate lifestyle, and, if necessary, antihypertensive treatment and low-dose aspirin reduces the risk of pre-eclampsia, preterm delivery, and other adverse pregnancy and neonatal outcomes in pregnancies complicated by type 1 diabetes. Despite the increasing use of diabetes technology (ie, continuous glucose monitoring and insulin pumps), the target of more than 70% time in range in pregnancy (TIRp 3·5-7·8 mmol/L) is often reached only in the final weeks of pregnancy, which is too late for beneficial effects on pregnancy outcomes. Hybrid closed-loop (HCL) insulin delivery systems are emerging as promising treatment options in pregnancy. In this Review, we discuss the latest evidence on pre-pregnancy care, management of diabetes-related complications, lifestyle recommendations, gestational weight gain, antihypertensive treatment, aspirin prophylaxis, and the use of novel technologies for achieving and maintaining glycaemic targets during pregnancy in women with type 1 diabetes. In addition, the importance of effective clinical and psychosocial support for pregnant women with type 1 diabetes is also highlighted. We also discuss the contemporary studies examining HCL systems in type 1 diabetes during pregnancies., Competing Interests: Declaration of interests KBen reports research funding and receipt of study devices from Medtronic for the investigator-initiated CRISTAL study, receipt of study devices from Dexcom, received consulting fees from AstraZeneca and Eli Lilly, and served on the speaker bureau for Novo Nordisk, AstraZeneca, and Mundipharma. SP reports grants from Dexcom and National Institute of Health (NIH), research support from Medtronic, and payment from diaTribe for an online article and participation on a DSMB from Sansum Diabetes Research Institute. LED reports grants from Diabetes Canada, Calgary Health Trust and Alberta Diabetes Institute, and in-kind, reduced cost, and loan of study devices from Medtronic, Dexcom, and Tandem Diabetes Care. CJL reports grants from the Helmsley Foundation, NIH (1R01DK120358–0), Tandem, Dexcom, Insulet, and Abbott Diabetes. CM reports consulting fees from Novo Nordisk, Sanofi, Merck Sharp and Dohme, Eli Lilly, AstraZeneca, Boehringer Ingelheim, Roche, Medtronic, ActoBio Therapeutics, Pfizer, Insulet, and Zealand Pharma, and serves or has served on the speaker bureau for Novo Nordisk, Sanofi, Eli Lilly, Boehringer Ingelheim, AstraZeneca, and Novartis. DSF reports grants from the Canadian Institute for Health Research; in-kind, reduced cost, and loan of study devices from Tandem Diabetes Care and Dexcom; has served on an advisory board for Novo Nordisk; and received honoraria from Sanofi and Novo Nordisk. RP reports multiple grants from ZonMw and Leading the Change (Netherlands governmental health-care research funds). SES has made webinars and a podcast on time in range and diabetes in pregnancy in cooperation with Abbott Diabetes, Medtronic, Eli Lilly, and Sanofi, and has served in advisory boards from Novo Nordisk and Eli Lilly. EB has received research funding from the Juvenile Diabetes Research Foundation and Dexcom and receipt of study devices from Dexcom. YCK reports grants from the Helmsley Foundation and NIH (1R01DK120358–0), product support from Dexcom, and is serving as site Principal Investigator on grants from Medtronic Diabetes, Tandem Diabetes, and Dexcom. ERM received research grants from Novo Nordisk for a randomised controlled trial investigating the use of faster aspart in comparison with aspart in pregnant women with pre-existing diabetes, a study evaluating the effect of insulin pump treatment in an international prospective cohort, and for the EXPECT study on the effect of insulin Degludec in comparison with insulin detemir in pregnant women with type 1 diabetes. In addition, ERM received funding from Novo Nordisk for lectures on diabetes in pregnancy and for attending the European Association for the Study of Diabetes Annual Meeting 2022. TB has received honoraria for participation on advisory boards for Novo Nordisk, Sanofi, Eli Lilly, Medtronic, Provention Bio, and Indigo Diabetes, and as a speaker for Astra Zeneca, Eli Lilly, Novo Nordisk, Medtronic, Abbott, Dexcom, Sanofi, and Roche. TB's institution, University Medical Centre Ljubljana, has received research grant support and travel expenses from Abbott, Medtronic, Novo Nordisk, Sanofi, Sandoz, Novartis, the EU, and the NIH–National Institute of Diabetes and Digestive and Kidney Diseases., (Copyright © 2023 Elsevier Ltd. All rights reserved.)