[01] Faehaa Azher Al-Mashhadane, Department of Dental Basic Sciences, University of Mosul, Mosul, Iraq. [02] Alyaa Azher Al-Mashhadane, Ministry of Health, Al-Salam Hospital, Mosul, Iraq. [03] Amer Abdul Rhman Taqa, Department of Dental Basic Sciences, University of Mosul, Mosul, Iraq.

Folate is required for metabolic processes and neural development. The aim of this paper was to review the effects of folic acid supplementation before and throughout pregnancy on fetal development, summarize research needs with a focus on studying the effects of correct dosage folic acid. Methods: Related publications were reviewed to determine and quantify associations of maternal use of folic acid before conception and during pregnancy as risk factor for Neural Tube Defects (NTD), Orofacial Clefts, ischemic heart diseases, Unmetabolised folic acid, Masking of B12 Deficiency Anemia and cancer. Evidence on maternal drug use before conception and during pregnancy as risk factor for developmental defect from epidemiological studies is still very limited. This review showed that a high prevalence of malformations and diseases that affect fetus could be related to the mother folic acid supplementation before and during pregnancy. Challenges in global prevalence estimation include quality of surveillance methods, geographic and socioeconomic factors, availability and use of folic acid, racial–ethnic and genetic factors, and limitations in education and access to care. For primary prevention of NTD in women with no prior affected pregnancy, 0.4 mg daily dose of folic acid was recommended and 4.0 mg daily dose was effective in preventing NTD in women with a prior affected pregnancy. Also Maternal supplementation in early pregnancy reduces the risk of oral cleft in infants, evidence from the literature serve to reassure women planning a pregnancy to consume folic acid during the periconception period to protect against oral clefts. Several studies have confirmed that folic acid supplementation before pregnancy was associated with a reduced risk of ischemic heart diseases, lower dietary folate intake during pregnancy was associated with increased risk. Folic acid may prevent or promote cancer development and progression depending on the timing of intervention In conclusion and based on the evidence evaluated, caution regarding under and/or over folic acid supplementation is warranted.

Folic Acid, Pregnancy, Dose

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