163 patients and 81 controls were included. There was a small but significant difference in age between patients and controls (31.7 vs. 34.1 years, respectively, p < 0.001). We observed 6.9% higher body weight (p = 0.002) and 9.3% higher BMI (p < 0.001) among patients. Parity was significantly lower for patients (1 vs. 2, p < 0.001). As expected, duration of pregnancy was significantly shorter in patients (241 vs. 279 days, p < 0.001) and their children had lower birth weight (2105 vs. 3432 g, p < 0.001). Controls were significantly longer postpartum at time of investigation (191 vs. 74 weeks, p < 0.001). Baseline characteristics are summarized in Table 1.

Ovarian reserve, represented by AMH, was 20% higher among patients compared to controls (2.4 vs. 2.0 µg/L). This difference remained significant after correction for age (p = 0.045). There was a significant inverse relation between age and AMH (B=–0.143, p = 0.002). No significant correlations between AMH and BMI or other cardiovascular function parameters were found. Cardiovascular function parameters showed less favourable results among patients; higher fasting glucose (4%, p = 0.016), insulin (81%, p < 0.001), systolic BP (5%, p = 0.001), diastolic BP (4%, p < 0.001), MAP (6%, p < 0.001) and triglycerides (29%, p = 0.002). Ovarian reserve and cardiovascular function are summarized in Table 2.

A correlation matrix of AMH and age, blood pressure and BMI is shown in Appendix 1, to show the associations between these measurements.

For the subgroup analysis, patients were divided in early (< 34 weeks) and late (≥ 34 weeks) onset of HDP. In comparison to controls, significant differences in age, weight, BMI, gravidity, parity, birth weight, gestational age at delivery and time postpartum at measurement were observed in both subgroups. No difference in AMH was observed in the early onset group compared to controls. However, significant higher AMH levels were observed in the late onset group, compared to controls (2.8 vs. 2.0 µg/L, p = 0.025).

In the early onset group, significantly higher fasting glucose levels (4%, p = 0.014) than controls were observed. Both subgroups showed comparable differences with higher insulin (98% in early and 70% in late onset, respectively, p < 0.001), systolic BP (6% and 5%, p < 0.05), diastolic BP (4% and 3%, p < 0.01), MAP (6% and 5%, p = 0.004) and triglycerides (both 29%, p < 0.05) than controls.

The comparison between the subgroups shows significantly higher BMI and borderline lower triglycerides in the early onset group. Birth weight and gestational age at delivery were lower among early onset cases, as could be expected. Results of the subgroup analysis are summarized in Table 3.