No abstract

No abstract

The quality of evidence in the document was rated using the criteria described in the Report of the Canadian Task Force on Preventative Health Care (Table 1). Summary Statement In Canada multivitamin tablets with folic acid are usually available in 3 formats: regular over-the-counter multivitamins with 0.4 to 0.6 mg folic acid, prenatal over-the-counter multivitamins with 1.0 mg folic acid, and prescription multivitamins with 5.0 mg folic acid. (III) Recommendations 1. Women should be advised to maintain a healthy folate-rich diet; however, folic acid/multivitamin supplementation is needed to achieve the red blood cell folate levels associated with maximal protection against neural tube defect. (III-A) 2. All women in the reproductive age group (12-45 years of age) who have preserved fertility (a pregnancy is possible) should be advised about the benefits of folic acid in a multivitamin supplementation during medical wellness visits (birth control renewal, Pap testing, yearly gynaecological examination) whether or not a pregnancy is contemplated. Because so many pregnancies are unplanned, this applies to all women who may become pregnant. (III-A) 3. Folic acid supplementation is unlikely to mask vitamin B12 deficiency (pernicious anemia). Investigations (examination or laboratory) are not required prior to initiating folic acid supplementation for women with a risk for primary or recurrent neural tube or other folic acid-sensitive congenital anomalies who are considering a pregnancy. It is recommended that folic acid be taken in a multivitamin including 2.6 ug/day of vitamin B12 to mitigate even theoretical concerns. (II-2A) 4. Women at HIGH RISK, for whom a folic acid dose greater than 1 mg is indicated, taking a multivitamin tablet containing folic acid, should be advised to follow the product label and not to take more than 1 daily dose of the multivitamin supplement. Additional tablets containing only folic acid should be taken to achieve the desired dose. (II-2A) 5. Women with a LOW RISK for a neural tube defect or other folic acid-sensitive congenital anomaly and a male partner with low risk require a diet of folate-rich foods and a daily oral multivitamin supplement containing 0.4 mg folic acid for at least 2 to 3 months before conception, throughout the pregnancy, and for 4 to 6 weeks postpartum or as long as breast-feeding continues. (II-2A) 6. Women with a MODERATE RISK for a neural tube defect or other folic acid-sensitive congenital anomaly or a male partner with moderate risk require a diet of folate-rich foods and daily oral supplementation with a multivitamin containing 1.0 mg folic acid, beginning at least 3 months before conception. Women should continue this regime until 12 weeks' gestational age. (1-A) From 12 weeks' gestational age, continuing through the pregnancy, and for 4 to 6 weeks postpartum or as long as breast-feeding continues, continued daily supplementation should consist of a multivitamin with 0.4 to 1.0 mg folic acid. (II-2A) 7. Women with an increased or HIGH RISK for a neural tu...

BackgroundThe aim of this guideline is to provide updated recommendations for Canadian genetic counsellors, medical geneticists, maternal fetal medicine specialists, clinical laboratory geneticists and other practitioners regarding the use of chromosomal microarray analysis (CMA) for prenatal diagnosis. This guideline replaces the 2011 Society of Obstetricians and Gynaecologists of Canada (SOGC)-Canadian College of Medical Geneticists (CCMG) Joint Technical Update.MethodsA multidisciplinary group consisting of medical geneticists, genetic counsellors, maternal fetal medicine specialists and clinical laboratory geneticists was assembled to review existing literature and guidelines for use of CMA in prenatal care and to make recommendations relevant to the Canadian context. The statement was circulated for comment to the CCMG membership-at-large for feedback and, following incorporation of feedback, was approved by the CCMG Board of Directors on 5 June 2017 and the SOGC Board of Directors on 19 June 2017.Results and conclusionsRecommendations include but are not limited to: (1) CMA should be offered following a normal rapid aneuploidy screen when multiple fetal malformations are detected (II-1A) or for nuchal translucency (NT) ≥3.5 mm (II-2B) (recommendation 1); (2) a professional with expertise in prenatal chromosomal microarray analysis should provide genetic counselling to obtain informed consent, discuss the limitations of the methodology, obtain the parental decisions for return of incidental findings (II-2A) (recommendation 4) and provide post-test counselling for reporting of test results (III-A) (recommendation 9); (3) the resolution of chromosomal microarray analysis should be similar to postnatal microarray platforms to ensure small pathogenic variants are detected. To minimise the reporting of uncertain findings, it is recommended that variants of unknown significance (VOUS) smaller than 500 Kb deletion or 1 Mb duplication not be routinely reported in the prenatal context. Additionally, VOUS above these cut-offs should only be reported if there is significant supporting evidence that deletion or duplication of the region may be pathogenic (III-B) (recommendation 5); (4) secondary findings associated with a medically actionable disorder with childhood onset should be reported, whereas variants associated with adult-onset conditions should not be reported unless requested by the parents or disclosure can prevent serious harm to family members (III-A) (recommendation 8).The working group recognises that there is variability across Canada in delivery of prenatal testing, and these recommendations were developed to promote consistency and provide a minimum standard for all provinces and territories across the country (recommendation 9).

No abstract