Background:
Homocysteine is a sulfur-containing amino acid that plays a significant role in vascular health. Elevated maternal homocysteine levels have been increasingly recognized as a risk factor for adverse pregnancy outcomes, including preeclampsia, neural tube defects, and fetal growth restriction.

Objective:
This study aimed to evaluate the clinical significance of elevated homocysteine levels during pregnancy and explore its relationship with maternal nutrition, genetic factors, and obstetric complications.

Methods:
A narrative review was conducted based on data from cohort studies, randomized trials, and hospital-based observational studies. The review focused on pregnant women with elevated homocysteine levels and analyzed associations with vitamin B12/folate status, MTHFR polymorphisms, and maternal–fetal outcomes.

Results:
Elevated homocysteine (>10 µmol/L) was significantly associated with a higher risk of severe preeclampsia, recurrent pregnancy loss, and neural tube defects. Nutritional deficiencies and genetic predispositions further exacerbated hyperhomocysteinemia. Strong correlations were observed between maternal and neonatal homocysteine levels.

Conclusion:
Homocysteine represents a modifiable risk factor in pregnancy. Early screening and nutritional interventions, particularly with folate and vitamin B12, may reduce complications and improve maternal–fetal health outcomes. Routine evaluation of homocysteine should be considered in high-risk pregnancies.

Maternal homocysteine concentration, Hyperhomocysteinemia in pregnancy, Pregnancy-related vascular complications, Folate and vitamin B12 deficiency, Genetic factors in obstetric risk, MTHFR gene polymorphism, Endothelial dysfunction during gestation, Prenatal metabolic screening, Nutritional interventions in antenatal care, Fetal outcomes and amino acid metabolism.

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