OBJECTIVE: To assess associations between vitamin-dependent homocysteine me ta bolism and vascular-related pregnancy complications by considering interval bet ween delivery and postpartam investigation and maternal age. METHODS: Casecontro l study performed at the University Medical Center Nijmegen in the Netherlands. Patients had experienced pregnancy-induced hypertension (n = 37), preeclampsia (n = 144), hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome (n = 104), recurrent early pregnancy loss (n = 544), abruptio placentae (n = 135), intrauterine growth restriction (n = 144), or intrauterine fetal death (n = 104) . Controls comprised 176 women with uncomplicated obstetric histories. Oral meth ionine loading tests and fasting vitamin profiles were performed more than 6 wee ks after delivery. Odds ratios and 95%confidence intervals were calculated afte r logistic regression analysis. RESULTS: Hyperhomocysteinemia was associated wit h an approximately 2-fold to 3-fold increased risk for pregnancy-induced hype rtension, abruptio placentae, and intrauterine growth restriction. Cobalamin def iciency was associated with HELLP syndrome, abruptio placentae, intrauterine gro wth restriction, and intrauterine fetal death. Pyridoxal 5phosphate deficiency i ncreased the risk for pregnancy-induced hypertension 4-fold. These association s lost their significance after adjustment for time interval and maternal age. H igh red cell folate was associated with a decreased risk for abruptio placentae and intrauterine growth restriction. An increased creatinine concentration was a ssociated with pregnancy-induced hypertension, preeclampsia, HELLP syndrome, an d abruptio placentae. CONCLUSION: Hyperhomocysteinemia and vitamin deficiencies are largely determined by the interval between delivery and postpartum investiga tion and by maternal age. Time interval and maternal age should be considered in the risk estimation for vascular-related pregnancy complications. OBJECTIVE: To assess associations between vitamin-dependent homocysteine ​​me ta bolism and vascular-related pregnancy complications by considering interval bet ween delivery and postpartam investigation and maternal age. METHODS: Casecontro l study performed at the University Medical Center Nijmegen in the Netherlands. Patients had experienced pregnancy-induced hypertension (n = 37), preeclampsia (n = 144), hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome = 135), intrauterine growth restriction (n = 144), or intrauterine fetal death (n = 104). Controls comprised 176 women with uncomplicated obstetric histories. Oral methionine loading tests and fasting vitamin profiles were performed more than 6 wee ks after delivery . Odds ratios and 95% confidence interval were calculated afte r logistic regression analysis. RESULTS: Hyperhomocysteinemia was associated wit h an approximately 2-fold to 3-fold i ncreased risk for pregnancy-induced hypertension, abruptio placentae, and intrauterine growth restriction. Cobalamin deficiency was associated with HELLP syndrome, abruptio placentae, intrauterine gro wth restriction, and intrauterine fetal death. Pyridoxal 5phosphate deficiency i ncreased the risk for pregnancy-induced hypertension 4-fold. These associations s lost their significance after adjustment for time interval and maternal age. High red cell folate was associated with a decreased risk for abruptio placentae and intrauterine growth restriction. An increased creatinine concentration was a ssociated with pregnancy-induced hypertension, preeclampsia, HELLP syndrome, an d abruptio placentae. CONCLUSION: Hyperhomocysteinemia and vitamin deficiencies are largely determined by the interval between delivery and postpartum investigations and by maternal age. Time interval and maternal age should be considered in the risk estimation for vascular- related pregnancy complications.