The most extremely unfavourable outcome of pregnancy is the death of the mother and newborn. Negative outcomes for mothers or babies can occur as a result of complications or issues during pregnancy, birthor the post-partum period. Early elevated maternal homocysteine (Hct) levels during pregnancy have been linked to altered placental development. There is evidence that suggests an elevated maternal blood Hct level is the new obstetrical risk factor, and the association between hyperhomocysteinemia (HHct) and numerous obstetrical problems was recently recognised. Hctis an essential amino acid, which contains sulphur and is formed from the metabolism of methionine. HHct has several known aetiologies, including genetic anomalies; a deficiency in folic acid, vitamin B6 and vitamin B12; hypothyroidism; old age; and renal illnesses. Vascular problems, coronary artery disease, atherosclerosis and embolic illnesses can all occur as a result of high blood levels of Hct. Hct levels are lower in normal pregnancies than it is in women who are not pregnant. Many pregnancy-related problems, including pre-eclampsia (PE), recurrent pregnancy loss (RPL), placental abruption, premature deliveryand foetal growth restriction (FGR) have been connected to HHct in recent research. We looked for pertinent literature using a thorough and systematic search from PubMed, Medline, Embase, Cochrane Library, Google, etc., and articles that were published before August 2022 based on serum Hct levels and various placenta-mediated complicationsfor this review. In this review,we describedthe synthesis andmetabolismof Hct in humans, Hct levels at various phases of normal pregnancyand the association between Hct and placenta-mediated pregnancy complications. The outcomes discovered can help obstetricians increase the likelihood of a successful pregnancy in cases where placenta-mediated issues are present. Lowering Hct levels with a high dose of folic acid tablets during the subsequent pregnancy may be useful for women who experienced these difficulties in prior pregnancies as a result of HHct.