Maternal metabolic factors and the association with gestational diabetes: A systematic review and meta-analysis

Abstract

Gestational diabetes (GDM) is associated with several adverse outcomes for the mother and child. Higher levels of individual lipids are associated with risk of GDM and metabolic syndrome (MetS), a clustering of risk factors also increases risk for GDM. Metabolic factors can be modified by diet and lifestyle. This review comprehensively evaluates the association between MetS and its components, measured in early pregnancy, and risk for GDM. Databases (Cumulative Index to Nursing and Allied Health Literature, PubMed, Embase, and Cochrane Library) were searched from inception to 5 May 2021. Eligible studies included ≥1 metabolic factor (waist circumference, blood pressure, fasting plasma glucose (FPG), triglycerides, and high-density lipoprotein cholesterol), measured at <16 weeks' gestation. At least two authors independently screened potentially eligible studies. Heterogeneity was quantified using I² . Data were pooled by random-effects models and expressed as odds ratio and 95% confidence intervals (CIs). Of 7213 articles identified, 40 unique articles were included in meta-analysis. In analyses adjusting for maternal age and body mass index, GDM was increased with increasing FPG (odds ratios [OR] 1.92; 95% CI 1.39-2.64, k = 7 studies) or having MetS (OR 2.52; 1.65, 3.84, k = 3). Women with overweight (OR 2.17; 95% CI 1.89, 2.50, k = 12) or obesity (OR 4.34; 95% CI 2.79-6.74, k = 9) also were at increased risk for GDM. Early pregnancy assessment of glucose or the MetS, offers a potential opportunity to detect and treat individual risk factors as an approach towards GDM prevention; weight loss for pregnant women with overweight or obesity is not recommended. Systematic review registration: PROSPERO CRD42020199225.

Keywords: body mass index; gestational diabetes; glucose; lipids; meta-analysis; metabolic syndrome; pregnancy.

FIGURE 1

PRISMA flow diagram

FIGURE 2

Meta‐analysis of early pregnancy body mass index (BMI) and odds of gestational diabetes. Values are odds ratios (OR) with 95% confidence intervals (CIs) for (A) unadjusted and (B) adjusted for maternal age, analyses. For overall effect, p‐value <0.05 was considered significant

FIGURE 3

Meta‐analysis of early pregnancy overweight and odds of gestational diabetes. Values are odds ratios (OR) with 95% confidence intervals (CIs) for (A) unadjusted and (B) adjusted for maternal age, analyses. For overall effect, p‐value <0.05 was considered significant

FIGURE 4

Meta‐analysis of early pregnancy obesity and odds of gestational diabetes. Values are odds ratios (OR) with 95% confidence intervals (CIs) for (A) unadjusted analysis and (B) adjusted for maternal age. For overall effect, p‐value <0.05 was considered significant

FIGURE 5

Meta‐analysis of blood pressure during early pregnancy and odds of gestational diabetes. Values are odds ratios (OR) with 95% confidence intervals (CIs) for (A) raised blood pressure (systolic blood pressure >130 mm Hg or diastolic blood pressure >85 mm Hg) and (B) systolic blood pressure; adjusted for maternal age, BMI, family history, and ethnicity. For overall effect, p‐value <0.05 was considered significant

FIGURE 6

Meta‐analysis of early pregnancy fasting plasma glucose and odds of gestational diabetes. Values are odds ratios (OR) with 95% confidence intervals (CIs) for (A) unadjusted and (B) adjusted for maternal age and BMI, analyses. For overall effect, p‐value <0.05 was considered significant

FIGURE 7

Meta‐analysis of early pregnancy glycosylated haemoglobin and odds of gestational diabetes. Values are odds ratios (OR) with 95% confidence intervals (CIs), adjusted for maternal body mass index (BMI). For overall effect, p‐value <0.05 was considered significant

FIGURE 8

Meta‐analysis of early pregnancy triglycerides (TG) and odds of gestational diabetes. Values are odds ratios (OR) with 95% confidence intervals (CIs) (A) per one unit increase in TG and (B) TG > 1.7 mmol/l, adjusted for maternal age and body mass index (BMI). For overall effect, p‐value <0.05 was considered significant

FIGURE 9

Meta‐analysis of early pregnancy high‐density lipoprotein cholesterol (HDL‐C) and odds of gestational diabetes. (A), Values are odds ratios (OR) with 95% confidence intervals (CIs) for one unit increase in HDL‐C adjusted for maternal age and body mass index (BMI). (B), Odds ratio with 95% CI for low HDL‐C (<1.3 mmol/l) adjusted for maternal age. For overall effect, p‐value <0.05 was considered significant

FIGURE 10

Meta‐analysis of early pregnancy metabolic syndrome and odds of gestational diabetes. Values are odds ratios (OR) with 95% confidence intervals (CIs) for (A) unadjusted and (B) adjusted for maternal age, body mass index (BMI) and family history, analyses. For overall effect, p‐value <0.05 was considered significant