Advertisement
JOGC

Woman's Pre-Conception Evaluation: Genetic and Fetal Risk Considerations for Counselling and Informed Choice

  • R. Douglas Wilson
    Correspondence
    Corresponding Author: Dr. R. Douglas Wilson, Department of Obstetrics and Gynecology, Cumming School of Medicine University of Calgary, Alberta Health Services Calgary Zone, Calgary, AB, Canada.
    Affiliations
    Department of Obstetrics and Gynecology, Cumming School of Medicine University of Calgary, Alberta Health Services Calgary Zone, Calgary, AB, Canada
    Search for articles by this author
Published:October 12, 2017DOI:https://doi.org/10.1016/j.jogc.2017.07.024

      Abstract

      Objective

      To inform reproductive and other health care providers about genetic and fetal risk information to consider during a woman/couples' pre-conception evaluation, including considerations for genetic risk assessment, genetic screening, or testing to allow for improved counselling and informed choice.

      Options

      This genetic information can be used for patient education, planning, and possible pre-conception and/or prenatal testing.

      Outcomes

      This information may allow improved risk assessment for pre-conception counselling for individual patients and their families.

      Evidence

      PubMed or Medline and the Cochrane Database were searched in May 2017 using appropriate key words (“pre-conception,” “genetic disease,” “maternal,” “family history,” “genetic,” “health risk,” “genetic health surveillance,” “prenatal screening,” “prenatal diagnosis,” “birth defects,” and “teratogen”). Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, and national and international medical specialty societies.

      Benefits, harms, and costs

      The benefits for the patient and her family include an increased understanding of relevant genetic risk pre-conception and in early pregnancy, and better pregnancy outcomes as a result of use of the information. The harm includes potential increased anxiety or psychological stress associated with the possibility of identifying genetic risks.

      Validation

      The evidence obtained was peer-reviewed by the Genetics Committee of The Society of Obstetricians and Gynaecologists of Canada.
      Consideration for Care Statements
      For this review article, the Consideration for Care Statements use the GRADE strength and quality as it is comparable for the clinician and the patient/public user.
      • 1.
        The provider needs to educate and counsel women regarding the importance of knowing her personal and her partner's family history (if available); and encourage the patients to consider discussing this issue prior to becoming pregnant. The provider should obtain or review a three-generation pedigree for the patient and her partner (Strong; Moderate).
      • 2.
        The provider needs to educate and counsel women about evaluating their lifestyle activities and their possible reproductive and fetal risks (weight, smoking, alcohol, drugs, medications) if a pregnancy were to occur without some planning (Strong; Moderate).
      • 3.
        The provider needs to educate and counsel women about the importance of optimizing and then managing the medical or surgical conditions and fetal teratogenic exposures that may require chronic or frequent use of medications or where scheduled surgery is being considered as part of their health care management (Strong; Moderate).
      • 4.
        The provider should offer relevant investigations for a history of recurrent pregnancy loss and consider how findings might relate to genetic/placental risk during a pregnancy with consideration for the elimination of thrombophilia testing for recurrent loss, intra-uterine growth restriction, pre-eclampsia, and abruption (Strong; Moderate).
      • 5.
        The provider should not undertake maternal serologic studies for cytomegalovirus and toxoplasmosis as part of routine prenatal laboratory studies (Strong; Moderate).
      • 6.
        The provider should review whether pregnancy planning or prevention is a primary consideration at each office visit. The provider should offer to educate and counsel the patient about the personal use and options available for using birth control to enhance the patient's reproductive planning and her ability to have a pregnancy when it is desired (Strong; Moderate).
      • 7.
        The provider should ask or assist the patient to consider or create a personal reproductive plan looking at “how many pregnancies do you (and your partner) want, when do you (and your partner) want to start, and what duration of spacing do you (and your partner) want?” Although this planning may have obstacles such as marital and occupation changes, some effort to plan should be introduced (Strong; Moderate).
      [GRADE from the Canadian Task Force on Preventive Health Care (www.canadiantaskforce.ca). For clinicians, Strong = The recommendation would apply to most individuals. Formal discussion aids are not likely to be needed to help individuals make decisions consistent with their values and preferences. For patients/public, Strong = We believe most people in this situation would want the recommended course of actions and only a small number would not. Quality of evidence (High, Moderate, Low) based on the confidence that the true effect lies close to that of the estimate of the effect.]
      Conclusion
      Pre-conception planning is presently underutilized by both patients and providers. Pre-conception genetic assessment is only a part of the counselling, education, and health management change that can improve perinatal and maternal morbidity and mortality. A published literature review on pre-conception genetic counselling identified mainly clinical cohort studies, surveys, and expert opinion with no RCTs. There is strong support for pre-conception counselling and moderate quality based on the understanding that most individuals would support and use pre-conception counselling when choice, timing, and ease of access is considered.

      Résumé

      Objectif

      Informer les fournisseurs de soins de santé génésiques et autres sur les renseignements relatifs aux risques génétiques et fœtaux dont il faut tenir compte durant l'évaluation préconceptionnelle d'une femme ou d'un couple, y compris l'évaluation des risques génétiques, le dépistage génétique ou les analyses, dans le but d'améliorer les conseils et de favoriser les choix éclairés.

      Options

      Ces renseignements génétiques peuvent servir à l'éducation des patientes, à la planification et potentiellement au dépistage préconceptionnel ou anténatal.

      Résultats

      Ces renseignements peuvent améliorer l'évaluation des risques lors des consultations préconceptionnelles pour les patientes et leur famille.

      Données

      Des recherches ont été effectuées dans PubMed, MEDLINE et la base de données Cochrane en mai 2017 avec des mots-clés appropriés (« pre-conception », « genetic disease », « maternal », « family history », « genetic », « health risk », « genetic health surveillance », « prenatal screening », « prenatal diagnosis », « birth defects » et « teratogen »). Nous avons également tenu compte de la littérature grise (non publiée) trouvée sur les sites Web d'organismes d'évaluation des technologies de la santé et d'autres organismes liés aux technologies de la santé et dans des collections de directives cliniques, et obtenue auprès d'associations nationales et internationales de médecins spécialistes.

      Avantages, inconvénients et coûts

      Parmi les avantages pour la patiente et sa famille, mentionnons l'amélioration de la compréhension des risques génétiques pertinents avant la conception et en début de grossesse, ainsi qu'une amélioration des issues de la grossesse grâce à l'utilisation des renseignements. Les inconvénients comprennent l'augmentation potentielle de l'anxiété ou du stress psychologique associés à la possibilité de trouver des risques génétiques.

      Validation

      Les données obtenues ont été évaluées par des pairs du Comité de génétique de la Société des obstétriciens et gynécologues du Canada.
      Énoncés de recommandations de soins
      Dans cet article de synthèse, les énoncés de recommandations de soins s'inspirent des critères de l'approche GRADE pour évaluer la qualité et la force des données probantes, car les conclusions sont comparables pour le clinicien et la patiente et utilisatrice publique.
      • 1.
        Le fournisseur de soins doit donner à ses patientes de l'information et des conseils sur l'importance de connaître leurs propres antécédents familiaux et ceux de leur partenaire (s'ils peuvent être obtenus), et les encourager à en discuter avant le début de la grossesse. Le fournisseur de soins devrait obtenir et analyser les antécédents familiaux des patientes et de leur partenaire sur trois générations (Forte; Moyenne).
      • 2.
        Le fournisseur de soins doit donner à ses patientes de l'information et des conseils sur l'évaluation de leur style de vie (poids, tabagisme, alcool, drogues, médicaments) et des risques potentiels pour la grossesse et le fœtus qui y sont associés en cas de grossesse non planifiée (Forte; Moyenne).
      • 3.
        Le fournisseur de soins doit donner à ses patientes de l'information et des conseils sur l'importance d'optimiser, puis de prendre en charge les interventions médicales ou chirurgicales et les expositions tératogènes fœtales associées à la prise chronique ou fréquente de médicaments, ainsi que les chirurgies planifiées envisagées dans le cadre de leur prise en charge médicale (Forte; Moyenne).
      • 4.
        Le fournisseur de soins devrait offrir les examens pertinents aux patientes ayant des antécédents de fausses couches à répétition afin de déterminer s'il y présence de risques génétiques et associés au placenta durant la grossesse, ainsi qu'envisager d'éliminer le recours au dépistage de la thrombophilie en cas de fausses couches à répétition, de retard de croissance intra-utérin, de prééclampsie et de décollement (Forte; Moyenne).
      • 5.
        Le fournisseur de soins ne devrait pas soumettre la mère à des analyses sérologiques pour la détection du cytomégalovirus et de la toxoplasmose dans le cadre des analyses de laboratoire prénatales systématiques (Forte; Moyenne).
      • 6.
        Le fournisseur de soins devrait vérifier lors de chaque visite si la patiente planifie activement ou tente de prévenir une grossesse. Il devrait offrir de l'information et des conseils à ses patientes sur leur utilisation personnelle de méthodes contraceptives pour optimiser la planification des naissances et leur capacité à tomber enceintes lorsqu'elles le désirent (Forte; Moyenne).
      • 7.
        Le fournisseur de soins devrait demander à ses patientes de créer un plan familial personnel – ou au moins d'y penser – ou les aider à le faire si nécessaire, afin qu'elles (et leur partenaire) déterminent le nombre de grossesses qu'elles souhaitent avoir, le moment où commencer les tentatives et l'intervalle souhaité entre les grossesses. Bien que le plan puisse être altéré par des changements touchant le couple et le travail, les patientes devraient au moins tenter de l'appliquer (Forte; Moyenne).
      [L'approche GRADE provient du Groupe d'étude canadien sur les soins de santé préventifs (www.canadiantaskforce.ca/?lang=fr). Pour les cliniciens : Forte = la recommandation s'applique à la plupart des personnes. Il est peu probable que des outils officiels d'aide à la discussion soient nécessaires pour que les patientes prennent des décisions qui respectent leurs valeurs et leurs préférences. Pour les patientes et membres du public : Forte = nous sommes d'avis que la plupart des gens dans cette situation opteraient pour les mesures recommandées, et seulement une faible proportion préférerait une autre option. L'évaluation de la qualité des données probantes (Élevée, Moyenne, Faible) est basée sur le degré de conviction que l'effet réel est proche de l'estimation.]
      Conclusion
      Actuellement, les patientes et leurs fournisseurs de soins n'ont pas suffisamment recours à la planification préconceptionnelle. Le dépistage génétique préconceptionnel n'est qu'un outil parmi toute une gamme d'interventions de conseil, d'éducation et de prise en charge de la santé qui pourraient réduire la morbidité et la mortalité maternelles et périnatales. Une revue de la littérature publiée portant sur les conseils génétiques avant la conception a cité principalement des études de cohortes en milieu clinique, des sondages et des opinions d'experts, mais aucun essai clinique randomisé. Le counselling préconceptionnel est fortement recommandé et appuyé par des données de qualité moyenne, considérant qu'une fois pris en compte les choix offerts, le moment de l'offre et la facilité d'accès, la plupart des patientes appuieraient le counselling préconceptionnel et y auraient recours.

      Key Words

      Abbreviations:

      ARR (adjusted risk ratio), ART (assisted reproduction technology), PGD (pre-implantation genetic diagnosis), RPL (recurrent pregnancy loss)
      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribe:

      Subscribe to Journal of Obstetrics and Gynaecology Canada
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      References

        • Health Canada
        Family-centred maternity and newborn care: national guidelines.
        Minister of Public Works and Government Services, Ottawa2000 (Available at)
        http://www.hc-sc.gc.ca
        Date accessed: April 1, 2016
        • Finer L.B.
        • Zolna M.R.
        Shifts in intended and unintended pregnancies in the United States, 2001–2008.
        Am J Public Health. 2014; 104: S43-S48
        • Mosher W.D.
        • Jones J.
        • Abma J.C.
        Intended and unintended births in the United States: 1982–2010.
        Natl Health Stat Report. 2012; 55: 1-28
        • Mazza D.
        • Chapman A.
        • Michie S.
        Barriers to the implementation of preconception care guidelines as perceived by general practitioners: a qualitative study.
        BMC Health Serv Res. 2013; 13: 36
        • Coffey K.
        • Shorten A.
        The challenge of preconception counselling: using reproductive life planning in primary care.
        J Am Assoc Nurse Pract. 2014; 26: 255-262
        • Chuang C.H.
        • Hwang S.W.
        • McCall-Hosenfeld J.S.
        • et al.
        Primary care physicians' perceptions of barriers to preventative reproductive health care in rural communities.
        Perspect Sex Reprod Health. 2012; 44: 78-83
        • Dirksen R.R.
        • Shulman B.
        • Teal S.B.
        • et al.
        Contraceptive counselling by general internal medicine faculty and residents.
        J Womens Health (Larchmt). 2014; 23: 707-713
        • Mitchell E.W.
        • Levis D.M.
        • Prue C.E.
        Preconception health: awareness, planning and communication among a sample of US men and women.
        Matern Child Health J. 2012; 16: 31-39
        • Moos M.K.
        • Cefalo R.C.
        Preconceptional health promotion: a focus for obstetric care.
        Am J Perinatol. 1987; 4: 63-67
        • Robbins J.M.
        • Tilford J.M.
        • Bird T.M.
        • et al.
        Hospitalizations of newborns with folate-sensitive birth defects before and after fortification of foods with folic acid.
        Pediatrics. 2006; 118: 906-915
        • Honein M.A.
        • Paulozzi L.J.
        • Mathews T.J.
        • et al.
        Impact of folic acid fortification of the US food supply on the occurrence of neural tube defects.
        JAMA. 2001; 284: 2981-2986
        • Freda M.C.
        • Moos M.K.
        • Curtis M.
        The history of preconception care: evolving guidelines and standards.
        Matern Child Health J. 2006; 10: S43-S52
      1. Recommendations for the use of folic acid to reduce the number of cases of spina bifida and other neural tube defects.
        MMWR Recomm Rep. 1992; 41: 1-7
        • Kitzmiller L.K.
        • Buchanan T.A.
        • Kjos S.
        • et al.
        Pre-conception care of diabetes, congenital malformations, and spontaneous abortions.
        Diabetes Care. 1996; 19: 514-541
        • Fuhrmann K.
        • Reiher H.
        • Semmler K.
        • et al.
        The effect of intensified conventional insulin therapy before and during pregnancy on the malformation rate in offspring of diabetic mothers.
        Exp Clin Endocrinol. 1984; 84: 173-177
        • Dunlop A.L.
        • Jack B.W.
        • Bottalica J.N.
        • et al.
        The clinical content of preconception care: women with chronic medical conditions.
        Am J Obstet Gynecol. 2008; 199: S310-S327
        • McElvy S.S.
        • Miodovnik M.
        • Rosenn B.
        • et al.
        A focused preconceptional and early pregnancy program in women with type I diabetes reduces perinatal mortality and malformation rates to general population levels.
        J Matern Fetal Med. 2000; 9: 14-20
      2. Committee Opinion No. 654: reproductive life planning to reduce unintended pregnancy.
        Obstet Gynecol. 2016; 127: e66-e69
      3. Committee Opinion No. 534: well-women visit.
        Obstet Gynecol. 2012; 120: 42104
        • American Congress of Obstetricians and Gynecologists
        Good health before pregnancy: preconception care.
        2017 (FAQ 056; Copyright ACOG March 2015)
        • American College of Obstetricians and Gynecologists
        ACOG Committee Opinion No. 313: the importance of preconception care in the continuum of women's health care.
        Obstet Gynecol. 2005; 106: 665-666
        • American College of Obstetricians and Gynecologists
        ACOG Committee Opinion No. 478: family history as a risk assessment tool.
        Obstet Gynecol. 2011; 117: 747-750
        • American College of Obstetricians and Gynecologists
        ACOG Committee Opinion No. 589: female age-related fertility decline.
        Obstet Gynecol. 2014; 123: 719-721
        • Schwartz D.
        • Mayaux M.J.
        Female fecundity as a function of age: results of artificial insemination in 2193 nulliparous women with azoospermic husbands. Federation CECOS.
        N Engl J Med. 1982; 306: 404-406
        • Centers for Disease Control and Prevention
        • American Society for Reproductive Medicine Society for Assisted Reproductive Technology
        2010 assisted reproductive technology. Fertility clinic success rates report.
        CDC, Atlanta (GA)2012 (Available at)
        • American College of Obstetricians and Gynecologists
        ACOG Committee Opinion No. 618: ovarian reserve testing.
        Obstet Gynecol. 2015; 125: 268-273
        • American College of Obstetricians and Gynecologists
        ACOG Committee Opinion No. 584: oocyte cryopreservation.
        Obstet Gynecol. 2014; 123: 221-222
        • Liu K.E.
        • Case A.
        No. 346 advanced reproductive age and fertility.
        J Obstet Gynaecol Can. 2017; 39: 685-695
        • Yu L.
        • Peterson B.
        • Inborn M.C.
        • et al.
        Knowledge, attitudes, and intentions toward fertility awareness and oocyte cryopreservation among obstetrics and gynecology resident physicians.
        Hum Reprod. 2016; 31: 403-411
        • Firth H.V.
        • Hurst J.A.
        • Hall J.G.
        Approach to the consultation with a child with dysmorphism, congenital malformation, or developmental delay.
        in: Firth H.V. Hurst J.A. Oxford desk reference clinical genetics. Oxford University Press, 2005: 4-5
        • Jones K.L.
        • Jones M.C.
        • Campo M.D.
        Genetics, genetic counseling, and prevention.
        in: Jones K.L. Jones M.C. Campo M.D. Smith's recognizable patterns of human malformation. 7th ed. Saunders Elsevier, 2013: 869-893 (Chapter 3)
        • Sanders R.C.
        • Blackmon L.R.
        • Hogge W.A.
        • et al.
        Structural fetal abnormalities the total picture.
        2nd ed. Mosby, St. Louis, MO2002: 17 (33, 67, 75, 78, 103, 143, 168, 178, 184, 209, 221, 225, 263)
        • Verma I.C.
        Global burden of genetic disease and the role of genetic screening.
        Semin Fetal Neonatal Med. 2015; 20: 354-363
        • Wilson R.D.
        • De Bie I.
        • Armour C.M.
        • et al.
        Opinion for Reproductive Genetic Carrier Screening: an update for all Canadian providers of maternity and reproductive healthcare in the era of direct consumer testing.
        J Obstet Gynaecol Can. 2016; 38: 742-762
      4. Committee Opinion No. 691: carrier screening for genetic conditions.
        Obstet Gynecol. 2017; 129: e41-e55
        • Crane J.
        • Mundle W.
        • Bouccoiran I.
        • et al.
        Parvovirus B19 infection in pregnancy.
        J Obstet Gynaecol Can. 2014; 36: 1107-1116
        • Money D.
        • Tulloch K.
        • Boucoiran I.
        • et al.
        Guidelines for the care of pregnant women living with HIV and interventions to reduce perinatal transmission.
        J Obstet Gynaecol Can. 2014; 36: S1-46
        • Gagnon A.
        • Davies G.
        • Wilson R.D.
        • et al.
        Prenatal invasive procedure in women with hepatitis B, hepatitis C, and/or human immunodeficiency virus infection.
        J Obstet Gynaecol Can. 2014; 36: 648-653
        • Money D.
        • Allen V.M.
        • Yudin M.H.
        • et al.
        The prevention of early-onset neonatal group B strepococcal disease.
        J Obstet Gynaecol Can. 2013; 35: e1-10
        • Paquet C.
        • Yudin M.H.
        • Allen V.M.
        • et al.
        Toxoplasmosis in pregnancy: prevention, screening, and treatment.
        J Obstet Gynaecol Can. 2013; 35: S1-S7
        • Loutfy M.R.
        • Margolese S.
        • Money D.M.
        • et al.
        Canadian HIV pregnancy planning guidelines.
        J Obstet Gynaecol Can. 2012; 34: 575-590
        • Shrim A.
        • Koren G.
        • Yudin M.H.
        • et al.
        Management of varicella infection (chicken pox) in pregnancy.
        J Obstet Gynaecol. 2012; 34: 287-292
        • Yinon Y.
        • Farine D.
        • Yudin M.H.
        • et al.
        Cytomegalovirous infection in pregnancy.
        J Obstet Gynaecol Can. 2010; 32: 355-362
        • Gruslin A.
        • Steben M.
        • Halperin S.
        • et al.
        Immunization in pregnancy.
        J Obstet Gynaecol Can. 2009; 31: 1085-1092
        • Rink D.B.
        • Lockwood C.J.
        Recurrent pregnancy loss.
        in: Creasy R.K. Resnik R. Iams J.D. Maternal-fetal medicine principles in practice. 7th ed. Elsevier Saunders, Philadelphia (PA)2014: 707-717
        • Page J.M.
        • Silver R.M.
        Genetic causes of recurrent pregnancy loss.
        Clin Obstet Gynecol. 2016; 59: 498-508
        • Krog M.C.
        • Mielsen H.S.
        • Christiansen O.B.
        • et al.
        Reproductive endocrinology in recurrent pregnancy loss.
        Clin Obstet Gynecol. 2016; 59: 474-486
        • Louis-Jacques A.F.
        • Maggio L.
        • Romero S.T.
        Prenatal Screening for thrombophilias: indications and controversies, an update.
        Clin Lab Med. 2016; 36: 421-432
        • Pritchard A.M.
        • Hendrix P.W.
        • Paides M.J.
        Hereditary thrombophilia and recurrent pregnancy loss.
        Clin Obstet Gynecol. 2016; 59: 487-497
        • Nahas R.
        • Saliba W.
        • Elias A.
        • et al.
        The prevalence of thrombophilia in women with recurrent fetal loss and outcome of anticoagulation therapy for the prevention of miscarriages.
        Clin Appl Thromb Hemost. 2016; (Epub ahead of print)https://doi.org/10.1177/10760029616675967
        • Russo M.
        • Suen M.
        • Bedaiwy M.
        • et al.
        Prevalence of uterine myomas among women with 2 or more recurrent pregnancy losses: a systematic review.
        J Minim Invasive Gynecol. 2016; 23: 702-706
        • Wang N.F.
        • Kolte A.M.
        • Larsen E.C.
        • et al.
        Immunologic abnormalities, treatments, and recurrent pregnancy loss: what is real and what is not?.
        Clin Obstet Gynecol. 2016; 59: 509-523
        • Chang J.
        • Boulet S.L.
        • Jeng G.
        • et al.
        Outcomes of in vitro fertilization with preimplantation genetic diagnosis: an analysis of the United States Assisted Reproductive Technology Surveillance Data, 2011–2012.
        Fertil Steril. 2016; 105: 394-400
        • Boulet S.L.
        • Kirby R.S.
        • Reefhuis J.
        • et al.
        Assisted reproductive technology and birth defects among liveborn infants in Florida, Massachusetts, and Michigan, 2000–2010.
        JAMA Pediatr. 2016; 170 (Epub ahead of print): e154934https://doi.org/10.1001/jamapediatrics.2015.4934
        • Dunietz G.L.
        • Holzman C.
        • McKane P.
        • et al.
        Assisted reproductive technology and the risk of preterm birth among primiparas.
        Fertil Steril. 2015; 103: 974-979
      5. Practice Bulletin No. 163. Screening for fetal aneuploidy.
        Obstet Gynecol. 2016; 127: 979-981
      6. Practice Bulletin No. 162. Prenatal diagnostic testing for genetic disorders.
        Obstet Gynecol. 2016; 127: 976-978
        • Wilson R.D.
        • Audibert F.
        • Brock J.
        • et al.
        Preconception folic acid and multivitamin supplementation for the primary and secondary prevention of neural tube defects and other folic acid-sensitive congenital anomalies.
        J Obstet Gynaecol Can. 2015; 37: 534-549
        • Dahdouh E.M.
        • Balayla J.
        • Audibert F.
        • et al.
        Pre-implantation genetic diagnosis and screening.
        J Obstet Gynaecol Can. 2015; 37: 451-463
        • Wilson R.D.
        • Audibert F.
        • Brock J.
        • et al.
        Prenatal screening, diagnosis, and pregnancy management of fetal neural tube defects.
        J Obstet Gynaecol Can. 2014; 36: 927-939
        • Gagnon A.
        • Davies G.
        • Wilson R.D.
        • et al.
        Prenatal invasive procedures in women with hepatitis C, and/or human immunodeficiency virus infections.
        J Obstet Gynaecol Can. 2014; 36: 648-653
        • Langlois S.
        • Brock J.
        • Wilson R.D.
        • et al.
        Current status in non-invasive prenatal detection of Down syndrome, trisomy 18, and trisomy 13 using cell-free DNA in maternal plasma.
        J Obstet Gynaecol Can. 2013; 35: 177-181
        • Cartier L.
        • Murphy-Kaulbeck L.
        • Wilson R.D.
        • et al.
        Counselling considerations for prenatal genetic screening.
        J Obstet Gynaecol Can. 2012; 34: 489-493
        • Johnson J.A.
        • Tough S.
        • Wilson R.D.
        • et al.
        Delayed child bearing.
        J Obstet Gynaecol Can. 2012; 34: 80-93
        • Duncan A.
        • Langlois S.
        • Wilson R.D.
        • et al.
        Use of array genomic hybridization technology in prenatal diagnosis in Canada.
        J Obstet Gynaecol Can. 2011; 33: 1256-1259
        • Langlois S.
        • Duncan A.
        • Wilson R.D.
        • et al.
        Use of DNA method, QF-PCR, in the prenatal diagnosis of fetal aneuploidies.
        J Obstet Gynaecol Can. 2011; 33: 955-960
        • Audibert F.
        • Gagnon A.
        • Wilson R.D.
        • et al.
        Prenatal screening for and diagnosis of aneuploidy in twin pregnancies.
        J Obstet Gynaecol Can. 2011; 33: 754-767
        • Chitayat D.
        • Langlois S.
        • Wilson R.D.
        • et al.
        Prenatal screening for fetal aneuploidy in singleton pregnancies.
        J Obstet Gynaecol Can. 2011; 33: 736-750
        • Wilson R.D.
        • Audibert F.
        • Brock J.
        • et al.
        Genetic considerations for a woman's pre-conception evaluation.
        J Obstet Gynaecol Can. 2011; 33: 57-64
        • Butt K.
        • Lim K.
        • Bly S.
        • et al.
        Determination of gestational age by ultrasound.
        J Obstet Gynaecol Can. 2014; 36: 171-181
        • Cargill Y.
        • Morin L.
        • Bly S.
        • et al.
        Content of a complete routine second trimester obstetrical examination and report.
        J Obstet Gynaecol Can. 2009; 31: 272-275
        • Lim K.
        • Butt K.
        • Crane J.M.
        • et al.
        Ultrasonographic cervical length assessment in predicting preterm birth in singleton pregnancies.
        J Obstet Gynaecol Can. 2011; 33: 486-499
        • Morin L.
        • Van den Hof M.C.
        • Bly S.
        • et al.
        Ultrasound evaluation of first trimester pregnancy complications.
        J Obstet Gynaecol Can. 2005; 27: 581-585
        • Le T.
        • Glede C.
        • Salem S.
        • et al.
        Initial evaluation and referral guidelines for management of pelvic/ovarian masses.
        J Obstet Gynaecol Can. 2009; 31: 668-673
        • Jemal A.
        • Siegel R.
        • Ward E.
        • et al.
        Life time probability of developing or dying from cancer.
        CA Cancer J Clin. 2007; 57: 43-66
        • Hook E.B.
        Rates of chromosomal abnormalities of different maternal ages.
        Obstet Gynecol. 1981; 58: 282-285
        • Morris J.K.
        • Wald N.J.
        • Mutton D.E.
        • et al.
        Comparison of models of maternal age-specific risk for Down syndrome live births.
        Prenat Diagn. 2003; 23: 252-258
        • Sharma R.
        • Agarwal A.
        • Rohra V.K.
        • et al.
        Effects of increased paternal age on sperm quality, reproductive outcome and associated epigenetic risks to offspring.
        Reprod Biol Endocrinol. 2015; 13: 35-55
        • Ramasamy R.
        • Chiba K.
        • Butler P.
        • et al.
        Male biological clock: a critical analysis of advanced paternal age.
        Fertil Steril. 2015; 103: 1402-1406
        • Zaragoza M.V.
        • Jacobs P.A.
        • James R.
        • et al.
        Nondisjunction of human acrocentric chromosomes: studies of 432 trisomic fetuses and liveborns.
        Hum Genet. 1994; 94: 411-417
        • Spano M.
        • Bondie J.P.
        • Hjollund H.I.
        • et al.
        Sperm chromatin damage impairs human fertility. The Danish First Pregnancy Planner Study Team.
        Fertil Steril. 2000; 73: 43-50
        • Cedars M.I.
        Introduction: childhood implications of parental aging.
        Fertil Steril. 2015; 103: 1379-1380
        • Choiriyyah I.
        • Sonenstein F.L.
        • Astone N.M.
        • et al.
        Men aged 15–44 in need of preconception care.
        Matern Child Health J. 2015; 19: 2358-2365
        • Benn P.A.
        Prenatal diagnosis of chromosomal disorders through amniocentesis.
        in: Milunsky A. Mulinsky J.M. Genetic disorders and the fetus. 6th ed. Wiley-Blackwell, Oxford2010: 194-272
        • Sachs A.
        • Blanchard L.
        • Buchanan A.
        • et al.
        Recommended pre-test counselling points for noninvasive prenatal testing using cell-free DNA: a 2015 perspective.
        Prenat Diagn. 2015; 35: 968-971
        • Neuman G.
        Counselling a patient with chronic illness before pregnancy.
        J Popul Ther Clin Pharmacol. 2014; 21: e520-e525
        • Buhimschi C.S.
        • Weiner C.P.
        Medications in pregnancy and lactation. Part 1. Teratology.
        Obstet Gynecol. 2009; 11: 166-188
        • Buhimschi C.S.
        • Weiner C.P.
        Medications in pregnancy and lactation. Part 2. Drugs with minimal or unknown human teratogeenic effect.
        Obstet Gynecol. 2009; 113: 417-432
        • Okun N.
        • Sierra S.
        • Wilson R.D.
        • et al.
        Pregnancy outcomes after assisted human reproduction.
        J Obstet Gynaecol Can. 2014; 36: 64-83
        • Black A.
        • Guilbert E.
        • Costescu D.
        • et al.
        Canadian contraception consensus. (Part 1 of 4) Chapters 1–3.
        J Obstet Gynaecol Can. 2015; 37: S1-28
        • Black A.
        • Guilbert E.
        • Costescu D.
        • et al.
        Canadian contraception consensus. (Part 2 of 4) Chapter 4–6.
        J Obstet Gynaecol Can. 2015; 37: S1-39
        • Black A.
        • Guilbert E.
        • Costescu D.
        • et al.
        Canadian contraception consensus (Part 3 of 4): chapter 7 – intrauterine contraception.
        J Obstet Gynaecol Can. 2016; 38: 182-222
        • Black A.
        • Guilbert E.
        • Costescu D.
        • et al.
        Canadian contraception consensus (Part 4 of 4).
        J Obstet Gynaecol Can. 2017; 39: 229-268
        • Stern J.
        • Joelsson L.S.
        • Tyden T.
        • et al.
        Is pregnancy planning associated with background characteristics and pregnancy-planning behaviour?.
        Acta Obstet Gynecol Scand. 2016; 95: 182-189
        • Upadhya K.K.
        • Jalazo E.R.
        • Connor K.
        • et al.
        Optimizing preconception health among young women: what are we missing?.
        J Pediatr Adolesc Gynecol. 2016; 29 (Epub ahead of print): 464-466
        • The Society of Obstetricians and Gynaecologists of Canada
        Sex & U.
        (Available at)
        http://www.sexualityandu.ca
        Date accessed: July 25, 2017
        • Alberta Health Services
        Ready or not Alberta.
        (Available at)
        https://readyornotalberta.ca
        Date accessed: July 25, 2017