Table 1: Demographics.

CharacteristicsCase group ()Control group () value

Age, years27 17–39]28 17–40]0.71
Parity, 1 0–4]1 0–4]0.87
Ethnicity
 Caucasian5 (8%)22 (34%)0.00
 African descent38 (59%)15 (23%)
 Other11 (17%)16 (25%)
 Unknown10 (16%)11 (17%)
Education level
 Lower education13 (20%)10 (16%)0.18
 Middle education21 (33%)12 (19%)
 Higher education7 (11%)12 (19%)
 Unknown23 (36%)29 (46%)
Comorbidities
 Overall13 (20%)12 (19%)0.12
 Preexisting hypertension1 (2%)2 (3%)
 Preexisting diabetes1 (2%)2 (3%)
 Renal/liver transplant1 (2%)0
 Renal malignancy in the past1 (2%)1 (2%)
 Irritable bowel syndrome01 (2%)
 Uterus myomatosus2 (3%)1 (2%)
 Primary hyperoxaluria type 11 (2%)0
 Asthma1 (2%)1 (2%)
 Hypothyroidism2 (3%)1 (2%)
 Sickle cell anemia2 (3%)1 (2%)
 Rheumatoid arthritis1 (2%)0
 Ehlers-Danlos type III01 (2%)
 Alpha thalassemia01 (2%)
 HIV infection1 (2%)1 (2%)
 IL-12 receptor deficiency01 (2%)
 Unknown40
Familial diseases
 None14 (22%)36 (56%)0.00
 Hypertension14 (22%)8 (13%)
 Diabetes6 (9%)3 (5%)
 Hypertension and diabetes18 (28%)13 (20%)
 Unknown12 (19%)4 (6%)
Number of fetuses
 Singleton pregnancy59 (92%)59 (92%)1.00
 Twin pregnancy5 (8%)5 (8%)

Data shown as median [range] or (%); patients could have more than one comorbidity.