Fig 1.
The process of selection of studies that were included in the review. Literature search included studies published from January 1, 1990 to January 14, 2021. Abbreviations: CHDs, congenital heart defects; ICD, International Classification of Disease; NOS, Newcastle-Ottawa Scale.
Table 1.
Summary table of characteristics of included studies.
Fig 2.
Maternal metabolic disorders and risk of any congenital heart defect in the offspring.
Any CHDs defined as the whole group of heart defects (only including studies that explicitly listed their definition thereof). Obesity is defined as BMI ≥ 30 kg/m2 unless other is stated; early-onset PE defined as diagnosed before gestational week 34; and PGDM are defined as DM1 or DM2. All risk estimates are adjusted unless other is stated; *, not adjusted; §, isolated defects; ¤, obesity defined from ICD-10 codes; £, BMI ≥ 35 kg/m2; ¥, BMI ≥ 28 kg/m2; †, BMI 35-<40 kg/m2; @, BMI 30.0–39.9; #, untreated hypertension; ‡, estimate only for severe CHDs. Abbreviations: BMI, body mass index; DM1, diabetes type 1; DM2, diabetes type 2; GDM, gestational diabetes; OR, odds ratio; PE, preeclampsia; PGDM, pre-gestational diabetes; PR, prevalence ratio; RR, risk ratio.
Table 2.
Overview of association between congenital heart defect subtypes and maternal exposures.