<b>Associations of High Body Mass Index and Excessive Gestational Weight Gain with Pregnancy Outcomes in Women with Type 1 Diabetes: A Systematic Review and Meta-analysis</b>

<p dir="ltr"><a href="" target="_blank"><b>BACKGROUND</b></a></p><p dir="ltr">The increased risk of pregnancy complications in type 1 diabetes is mainly attributed to maternal hyperglycemia. However, it is unclear if other potentially-modifiable factors, also contribute to risk in this population.</p><p dir="ltr"><b>PURPOSE</b></p><p dir="ltr">To assess if high body-mass-index (BMI) and excessive gestational-weight-gain (GWG) are associated with perinatal complications in type 1 diabetes.</p><p dir="ltr"><b>DATA SOURCES</b></p><p dir="ltr">We searched MEDLINE, Embase, PubMed, Scopus, Web of Science and Cochrane databases to January 2024.</p><p dir="ltr"><b>STUDY SELECTION</b></p><p dir="ltr">Studies examining associations between periconception BMI or GWG and perinatal complications in type 1 diabetes were included.</p><p dir="ltr"><b>DATA EXTRACTION</b></p><p dir="ltr">We used a predesigned data extraction template to extract study data including year, country, sample size, participants’ characteristics, exposure and outcomes.</p><p dir="ltr"><b>DATA SYNTHESIS</b></p><p dir="ltr">We included 29 studies (18,965 pregnancies; 1978-2019) in the meta-analysis. <a href="" target="_blank">A 1kg/m²/1kgincrease in preconception BMI or GWG was associated with a 3% and 11% increase in perinatal complications respectively (BMI OR 1.03 (95%CI 1.01-1.06); GWG OR 1.11 (95%CI 1.04-1.18)). Preconception BMI ≥ 25kg/m² or excessive GWG was associated with a 22% and 50% increase in perinatal complications respectively (BMI OR 1.22 (95%CI 1.11-1.34); GWG OR 1.50 (95%CI 1.31-1.73)).</a></p><p dir="ltr">BMI was associated with congenital malformation, preeclampsia, and neonatal-intensive-care-unit admission. Excessive GWG was associated with preeclampsia, Caesarean delivery, large-for-gestational-age and macrosomia.</p><p dir="ltr"><b>LIMITATIONS</b></p><p dir="ltr">Retrospective study design, variable measurement for exposures /outcomes, small number of studies for some outcomes, no data from Asia and Africa.</p><p dir="ltr"><b>CONCLUSIONS</b></p><p dir="ltr">Addressing maternal BMI pre-pregnancy and preventing excessive GWG should be key clinical priorities to improve outcomes in pregnant women with type 1 diabetes.</p><p><br></p>