A systematic review and meta-analysis «Andraweera PH, Lassi ZS. Cardiovascular Risk Facto...»1 compared cardiometabolic risk factors among children and adults born from a pregnancy complicated by maternal pre-eclampsia to those among other children and adults. The meta-analysis included literature published in English by 31 August 2017. It comprised result from 15 original articles with 1 599 offspring born from a pregnancy complicated by pre-eclampsia and 51 430 controls, aged 0 to 30 years, predominantly from high-income countries. Those born from a pre-eclamptic pregnancy had 5.17 mmHg higher systolic (95 % CI 1.60-8.73) and 4.06 mmHg higher diastolic (95 % CI 0,67-7.44) blood pressure. Of the studies, 13 included information on BMI at ages 0 to 30 years (n = 1 752 + 51 541), and it was 0.36 kg/m² higher (95 % CI 0.04-0.68). No difference was found in total cholesterol (n = 396 + 3 798, mean difference 0.47 mmol/l, 95 % CI -0.21-1.16), LDL cholesterol (n = 268 + 2 465, mean difference 0.12 mmol/l, 95 % CI -0.09-0.34), HDL cholesterol (n = 503 + 7 181, mean difference 0.05 mmol/l, 95 % CI -0.47-0.56), triglycerides (n = 215 + 1 061, mean difference 0.05 mmol/l, 95 % CI -0.13-0.23), fasting glucose (n = 486 + 3 848, mean difference 0.01 mmol/l, 95 % CI -0.03-0.06) or fasting insulin (n = 215 + 1 061, mean difference 0.25 SD units, 95 % CI -0.03-0.53).

• Study quality: moderate
• Applicability: good
• Comment: The meta-analysis included two studies in newborns; for one of these studies «Howlader MZ, Parveen S, Tamanna S ym. Oxidative st...»2 of 15 pre-eclamptic participants and 20 controls, maternal blood pressure values instead of child values had been included. Severity of pre-eclampsia, gestational age or relative birth weight were not taken into account.

A systematic review «Jansen MA, Pluymen LP, Dalmeijer GW ym. Hypertensi...»3 assessed cardiometabolic risk factors in offspring aged 2 to 18 years in literature published by January 2019, predominantly from high-income countries, with separate comparisons of those born from a pregnancy complicated by pre-eclampsia with controls, and of those born from a pregnancy complicated by gestational hypertension with controls. No meta-analysis was performed. The conclusions were based on the proportions of articles with statistically significant difference in each outcome variable. As to comparisons between offspring born from pre-eclamptic and normotensive pregnancies, 3 out of 10 studies showed higher systolic and diastolic blood pressure, and of 5 studies assessed, no study showed a difference in plasma lipids. As to comparisons between offspring born from pregnancies with gestational hypertension and offspring from normotensive pregnancies, 4/5 studies reported higher systolic and 3/5 higher diastolic blood pressure.

• Study quality: low
• Applicability: moderate
• Comment: It is unclear whether the lack of a statistically significant difference in an individual study is due to a true lack of difference or insufficient statistical power.

A meta-analysis «Wang LB, Qu B, Xu P ym. Preeclampsia exposed offsp...»4 included 16 studies published by March 2019, mostly from high-income countries, comparing 2 353 offspring born from a pregnancy complicated by pre-eclampsia with 68 492 controls who were not born from such pregnancy. Mean age was 15.5 years. Those born from a pre-eclamptic pregnancy had 0.54 kg/m² higher body mass index (BMI; 95 % CI 0.27-0.82) and were more likely to be obese (odds ratio 2.12, 95 % CI 1.70-2.66). Six studies reported on waist circumference, which was on average 1.37 cm longer (95 % CI 0.67-2.06). Four studies reported sex-specific analyses for BMI. Among girls (n = 416 + 20 815), mean difference was 0.89 kg/m² (95 % CI 0.55-1.23) and among boys (n = 277 + 10 313) 0.61 kg/m² (95 % CI -0.13-1.35).

• Study quality: high
• Applicability: good
• Comment: Severity of pre-eclampsia, gestational age or relative birth weight were not taken into account.

An individual-participant meta-analysis «Hovi P, Vohr B, Ment LR ym. Blood Pressure in Youn...»5 compared blood pressure in young adults born preterm at very low birth weight (VLBW; < 1 500 g) and controls born at term. Information on maternal pre-eclampsia (a frequent cause underlying preterm birth) was available in 7 studies, which included 928 VLBW adults, of whom 154 (16.6 %) were exposed to maternal pre-eclampsia, and a comparison group of 623 adults born at term. Compared with those born at term, those born preterm VLBW from a pre-eclamptic pregnancy had 5.8 mmHg higher systolic (95 % CI 3.6-7.9) and 4.2 mmHg higher diastolic (95 % CI 2.7-5.8) blood pressure. Correspondingly, those born preterm VLBW from a non-pre-eclamptic pregnancy had 3.8 mmHg higher systolic (95 % CI 2.4-5.1) and 2.0 mmHg higher diastolic (95 % CI 1.0-2.9) blood pressure. When SGA and pre-eclampsia were entered in simultaneous regression models within the VLBW subjects, pre-eclampsia was associated with 2.3 mm Hg (95 % CI -0.1-4.5) higher systolic and 1.8 mm Hg (95 % CI 0.5-3.1) higher diastolic blood pressure, whereas SGA status was associated with 2.7 mm Hg (95 % CI -0.4-5.7) lower systolic and 0.3 mm Hg (95 % CI -1.9-2.4) lower diastolic pressure.

• Study quality: high
• Applicability: good
• Comment: Being born preterm at very low birth weight (VLBW, < 1 500g) is per se a risk factor of higher blood pressure in adult life. The paper shows that maternal pre-eclampsia is associated with higher blood pressure also among the important subgroup of those born preterm at VLBW.