1Dennis, CL, Falah-Hassani, K, Shiri, R. Prevalence of antenatal and postnatal anxiety: systematic review and meta-analysis. Br J Psychiatry 2017; 210: 315–23.
2Heron, J, O'Connor, TG, Evans, J, Golding, J, Glover, V. The course of anxiety and depression through pregnancy and the postpartum in a community sample. J Affect Disord 2004; 80: 65–73.
3Dunkel-Schetter, C, Lobel, M. Pregnancy and birth: a multilevel analysis of stress and birth weight. In Handbook of Health Psychology 2 (eds Revenson, T, Baum, A, Singer, J): 427–53. Lawrence Erlbaum, 2011.
4Stein, A, Pearson, RM, Goodman, SH, Rapa, E, Rahman, A, McCallum, M, et al. Effects of perinatal mental disorders on the fetus and child. Lancet 2014; 384: 1800–19.
5Rubertsson, C, Hellström, J, Cross, M, Sydsjö, G. Anxiety in early pregnancy: prevalence and contributing factors. Arch Womens Ment Health 2014; 17: 221–8.
6National Institute for Health and Care Excellence. Antenatal and Postnatal Mental Health: Clinical Management and Service Guidance (CG192). NICE, 2014.
7Milgrom, J, Gemmil, A, Bilszta, JL, Hayes, B, Barnett, B, Brooks, J, et al. Antenatal risk factors for postnatal depression: a large prospective study. J Affect Disord 2008; 108: 147–57.
8Grant, K, McMahon, C, Austin, MP. Maternal anxiety during the transition to parenthood: a prospective study. J Affect Disord 2008; 108: 101–11.
9Verreault, N, DaCosta, D, Marchand, A, Ireland, K, Dritsa, M, Khalife, S. Rates and risk factors associated with depressive symptoms during pregnancy and with postpartum onset. J Psychosom Obstet Gynaecol 2014; 35: 84–91.
10Sutter-Dallay, AL, Giaconne-Marcesche, V, Glatigry-Dallay, E, Verdoux, H. Women with anxiety disorders during pregnancy are at increased risk of intense postnatal depressive symptoms: a prospective survey of the MATQUID cohort. Eur Psychiatr 2004; 19: 459–63.
11Austin, MP, Tully, L, Parker, G. Examining the relationship between antenatal anxiety and postnatal depression. J Affect Disord 2007; 101: 169–74.
12Field, T, Diego, M, Hernandez-Reif, M, Figuereido, B, Deeds, O, Ascencio, A, et al. Comorbid depression and anxiety effects on pregnancy and neonatal outcome. Infant Behav Dev 2010; 33: 23–9.
13Diego, MA, Jones, NA, Field, T, Hernandez-Reif, M, Schanberg, S, Kuhn, C, et al. Maternal psychological distress, prenatal cortisol, and fetal weight. Psychosom Med 2006; 68: 747–53.
14Berle, JO, Mykletun, A, Daltveit, AK, Rasmussen, S, Holsten, F, Dahl, AA. Neonatal outcomes in offspring of women with anxiety and depression during pregnancy: a linkage study from The Nord-Trøndelag Health Study (HUNT) and Medical Birth Registry of Norway. Arch Womens Ment Health 2005; 8: 181–9.
15Ding, XX, Wu, YL, Xu, SJ, Zhu, RP, Jia, XM, Zhang, SF, et al. Maternal anxiety during pregnancy and adverse birth outcomes: a systematic review and meta-analysis of prospective cohort studies. J Affect Disord 2014; 159: 103–10.
16Talge, NM, Neal, C, Glover, V. Antenatal maternal stress and long-term effects on child neurodevelopment: how and why? J Child Psychol Psychiatry 2007; 48: 245–61.
17Van Der Bergh, BR, Mulder, EJ, Mennes, M, Glover, V. Antenatal maternal anxiety and stress and the neurobehavioural development of the fetus and child: links and possible mechanisms. A review. Neurosci Biobehav Rev 2005; 29: 237–58.
18Spitzer, RL, Kroenke, K, Williams, JB, Löwe, B. A brief measure for assessing generalized anxiety disorder: the GAD-7. Arch Intern Med 2006; 166: 1092–7.
19Scottish Intercollegiate Guidelines Network (SIGN). Management of Perinatal Mood Disorders (127). SIGN, 2012.
20National Institute for Health and Care Excellence. Common Mental Health Disorders: Identification and Pathways to Care (CG123). NICE, 2011.
21Austin, MP. Antenatal screening and early intervention for ‘perinatal’ distress, depression and anxiety: where to from here? Arch Womens Ment Health 2004; 7: 1–6.
22American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders (5th edn) (DSM-5). American Psychiatric Publishing, 2013.
23World Health Organization (WHO). The ICD-10 Classification of Mental and Behavioural Disorders: Clinical Descriptions and Diagnostic Guidelines. WHO, 1992.
24Goodman, JH, Chenausky, KL, Freeman, MP. Anxiety Disorders during pregnancy: a systematic review. J Clin Psychiatry 2014; 75: 1153–84.
25Evans, K, Spiby, H, Morrell, CJ. A psychometric systematic review of self-report instruments to identify anxiety in pregnancy. J Adv Nurs 2015; 71: 1986–2001.
26Swallow, BL, Lindow, SW, Masson, EA, Hay, DM. The use of the General Health Questionnaire (GHQ-28) to estimate prevalence of psychiatric disorder in early pregnancy. Psychol Health Med 2003; 8: 213–7.
27Marchesi, C, Ampollini, P, Paraggio, C, Giaracuni, G, Ossola, P, DePanfilis, C, et al. Risk factors for panic disorder in pregnancy: a cohort study. J Affect Disord 2014; 156: 134–8.
28Huizink, AC, Mulder, EJ, Robles De Medina, PG, Visser, GH, Buitelaar, JK. Is pregnancy anxiety a distinctive syndrome? Early Hum Dev 2004; 79: 81–91.
29Phillips, J, Sharpe, L, Matthey, S, Charles, M. Maternally focussed worry. Arch Womens Ment Health 2009; 12: 409–18.
30Poikkeus, P, Saisto, T, Unkila-Kallio, L, Punamaki, RL, Repokari, L, Vilska, S, et al. Fear of childbirth and pregnancy-related anxiety in women conceiving with assisted reproduction. Obstet Gynecol 2006; 108: 70–6.
31Huizink, AC, Delforterie, MJ, Scheinin, NM, Tolvanen, M, Karlsson, L, Karlsson, H. Adaption of pregnancy anxiety questionnaire–revised for all pregnant women regardless of parity: PRAQ-R2. Arch Womens Ment Health 2016; 19: 125–32.
32Dunkel Schetter, C, Tanner, L. Anxiety, depression and stress in pregnancy: implications for mothers, children, research, and practice. Curr Opin Psychiatry 2012; 25: 141–48.
33Westerneng, M, de Cock, P, Spelten, ER, Honig, A, Hutton, EK. Factorial invariance of pregnancy-specific anxiety dimensions across nulliparous and parous pregnant women. J Health Psychol 2015; 20: 164–72.
34Blackmore, ER, Gustafsson, H, Gilchrist, M, Wyman, C, O'Connor, TG. Pregnancy-related anxiety: evidence of distinct clinical significance from a prospective longitudinal study. J Affect Disord 2016; 197: 251–8.
35Meades, R, Ayers, S. Anxiety measures validated in perinatal populations: a systematic review. J Affect Disord 2011; 133: 1–15.
36Brunton, RJ, Dryer, R, Saliba, A, Kohlhoff, J. Pregnancy anxiety: a systematic review of current scales. J Affect Disord 2015; 176: 24–34.
37Centre for Reviews and Dissemination (CRD). Systematic Reviews: CRD's Guidance for Undertaking Reviews in Health Care. CRD, 2009.
38Terwee, CB. Protocol for Systematic Reviews of Measurement Properties. COSMIN, 2011.
39Moher, D, Liberati, A, Tetzlaff, J, Altman, DG, The PRISMA Group. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. Ann Intern Med 2009; 151: 264–70.
40Leeflang, MM, Scholten, RJ, Rutjes, AW, Reitsma, JB, Bossuyt, PM. Use of methodological search filters to identify diagnostic accuracy studies can lead to the omission of relevant studies. J Clin Epidemiol 2006; 59: 234–40.
41Whiting, P, Westwood, M, Beynon, R, Burke, M, Sterne, JA, Glanville, J. Inclusion of methodological filters in searches for diagnostic test accuracy studies misses relevant studies. J Clin Epidemiol 2011; 64: 602–7.
42McHugh, ML. Interrater reliability: the kappa statistic. Biochem Med 2012; 22: 276–82.
43Mokkink, LB, Terwee, CB, Patrick, DL, Alonso, J, Stratford, PW, Knol, DL, et al. The COSMIN study reached international consensus on taxonomy, terminology, and definitions of measurement properties for health-related patient-reported outcomes. J Clin Epidemiol 2010; 63: 737–45.
44Mokkink, LB, Terwee, CB, Knol, DL, Stratford, PW, Alonso, J, Patrick, DL, et al. The COSMIN checklist for evaluating the methodological quality of studies on measurement properties: a clarification of its content. BMC Med Res Methodol 2010; 10: 1–8.
45Terwee, CB, Mokkink, LB, Knol, DL, Ostelo, RW, Bouter, LM, de Vet, HC. Rating the methodological quality in systematic reviews of studies on measurement properties: a scoring system for the COSMIN checklist. Qual Life Res 2012; 21: 651–7.
46Terwee, CB, Bot, SD, de Boer, MR, van der Windt, DA, Knol, DL, Dekker, J, et al. Quality criteria were proposed for measurement properties of health status questionnaires. J Clin Epidemiol 2007; 60: 34–42.
47Streiner, DL, Norman, GR, Cairney, J. Health Measurement Scales: A Practical Guide to Their Development and Use (5th edn). Oxford University Press, 2014.
48DeVellis, RF. Scale Development, Theory and Applications (3rd edn). SAGE Publication, 2012.
49Bartholomew, D, Knotts, M, Moustaki, I. Latent Variable Models and Factor Analysis: A Unified Approach (3rd edn). John Wiley & Sons, 2011.
50Tabachnick, BG, Fidell, LS. Using Multivariate Statistics (5th edn). Pearson Education Inc., 2007.
51Bayrampour, H, McDonald, S, Fung, T, Tough, S. Reliability and validity of three shortened versions of the State Anxiety Inventory scale during the perinatal period. J Psychosom Obstet Gynecol 2014; 35: 101–7.
52Brouwers, EP, van Baar, AL, Pop, VJ. Does the Edinburgh Postnatal Depression Scale measure anxiety? J Psychosom Res 2001; 51: 659–63.
53Carmona Monge, FJ, Peñacoba-Puente, C, Marín Morales, D, Carretero Abellán, I. Factor structure, validity and reliability of the Spanish version of the Cambridge Worry Scale. Midwifery 2012; 28: 112–9.
54Coates, R, Ayers, S, Visser, R. Factor structure of the Edinburgh Postnatal Depression Scale in a population-based sample. Psychol Assess 2017; 29: 1016–27.
55Fenaroli, V, Saita, E. Fear of childbirth: a contribution to the validation of the Italian version of the Wijma Delivery Expectancy/Experience Questionnaire (WDEQ). TPM Test Psychom Methodol Appl Psychol 2013; 20: 131–54.
56Garthus-Niegel, S, Størksen, HT, Torgersen, L, Von Soest, T, Eberhard-Gran, M. The Wijma Delivery Expectancy/Experience Questionnaire - a factor analytic study. J Psychosom Obstet Gynaecol 2011; 32: 160–3.
57Gourounti, K, Lykeridou, K, Taskou, C, Kafetsios, K, Sandall, J. A survey of worries of pregnant women: reliability and validity of the Greek version of the Cambridge Worry Scale. Midwifery 2012; 28: 746–53.
58Green, JM, Kafetsios, K, Statham, HE, Snowdon, CM. Factor structure, validity and reliability of the Cambridge Worry Scale in a pregnant population. J Health Psychol 2003; 8: 753–64.
59Haines, HM, Pallant, JF, Fenwick, J, Gamble, J, Creedy, DK, Toohill, J, et al. Identifying women who are afraid of giving birth: a comparison of the fear of birth scale with the WDEQ-A in a large Australian cohort. Sex Reprod Healthc 2015; 6: 204–10.
60Johnson, R, Slade, P. Does fear of childbirth during pregnancy predict emergency caesarean section? BJOG An Int J Obstet Gynaecol 2002; 109: 1213–21.
61Jomeen, J, Martin, C. Is the hospital anxiety and depression scale (HADS) a reliable screening tool in early pregnancy? Psychol Health 2004; 19: 787–800.
62Jomeen, J, Martin, CR. The factor structure of the Cambridge Worry Scale in early pregnancy. J Prenat Perinat Psychol Heal 2005; 20: 25–48.
63Jomeen, J, Martin, CR. Confirmation of an occluded anxiety component within the Edinburgh Postnatal Depression Scale (EPDS) during early pregnancy. J Reprod Infant Psychol 2005; 23: 143–54.
64Karimova, G, Martin, C. A psychometric evaluation of the Hospital Anxiety and Depression Scale during pregnancy. Psychol Health Med 2003; 8: 89–103.
65Levin, JS. The factor structure of the pregnancy anxiety scale. J Health Soc Behav 1991; 32: 368–81.
66Marteau, TM, Bekker, H. The development of a six-item short-form of the state scale of the Spielberger State-Trait Anxiety Inventory (STAI). Br J Clin Psychol 1992; 31: 301–306.
67Matthey, S, Valenti, B, Souter, K, Ross-Hamid, C. Comparison of four self-report measures and a generic mood question to screen for anxiety during pregnancy in English-speaking women. J Affect Disord 2013; 148: 347–51.
68Öhman, SG, Grunewald, C, Waldenström, U. Women's worries during pregnancy: testing the Cambridge Worry Scale on 200 Swedish women. Scand J Caring Sci 2003; 17: 148–52.
69Petersen, JJ, Paulitsch, MA, Guethlin, C, Gensichen, J, Jahn, A. A survey on worries of pregnant women--testing the German version of the Cambridge worry scale. BMC Public Health 2009; 9: 490–98.
70Simpson, W, Glazer, M, Michalski, N, Steiner, M, Frey, BN. Comparative efficacy of the generalized anxiety disorder 7-item scale and the Edinburgh Postnatal Depression Scale as screening tools for generalized anxiety disorder in pregnancy and the postpartum period. Can J Psychiatry 2014; 59: 434–40.
71Swalm, D, Brooks, J, Doherty, D, Nathan, E, Jacques, A. Using the Edinburgh Postnatal Depression Scale to screen for perinatal anxiety. Arch Womens Ment Health 2010; 13: 515–22.
72Tendais, I, Costa, R, Conde, A, Figueiredo, B. Screening for depression and anxiety disorders from pregnancy to postpartum with the EPDS and STAI. Span J Psychol 2014; 17: 1–9.
73Wijma, K, Wijma, B, Zar, M. Psychometric aspects of the W-DEQ; a new questionnaire for the measurement of fear of childbirth. J Psychosom Obstet Gynecol 1998; 19: 84–97.
74Zhong, QY, Gelaye, B, Zaslavsky, AM, Fann, JR, Rondon, MB, Sanchez, SE, et al. Diagnostic validity of the generalized anxiety disorder-7 (GAD-7) among pregnant women. PLoS ONE 2015; 10: 1–17.
75Cox, J, Holden, J, Sagovsky, R. Detection of postnatal depression. Development of the 10-item Edinburgh Postnatal Depression Scale. Br J Psychiatry 1987; 150: 782–6.
76Murray, D, Cox, JL. Screening for depression during pregnancy with the Edinburgh Depression Scale (EDDS). J Reprod Infant Psychol 1990; 8: 99–107.
77Green, J, Murray, D. The use of the Edinburgh Postnatal Depression Scale in research to explore the relationship between antenatal and postnatal dysphoria. In Perinatal Psychiatry: Use and Misuse of the Edinburgh Postnatal Depression Scale (eds Cox, J and Holden, J): 180–98. Gaskell, 1994.
78Pop, VJ, Komproe, IH, van Son, MJ. Characteristics of the Edinburgh Post Natal Depression Scale in The Netherlands. J Affect Disord 1992; 26: 105–10.
79Ross, LE, Gilbert Evans, SE, Sellers, EM, Romach, MK. Measurement issues in postpartum depression, pt 1: anxiety as a feature of postpartum depression. Arch Womens Ment Health 2003; 6: 51–7.
80Matthey, S, Fisher, J, Rowe, H. Using the Edinburgh postnatal depression scale to screen for anxiety disorders: conceptual and methodological considerations. J Affect Disord 2013; 146: 224–30.
81Child, D. The Essentials of Factor Analysis (3rd edn). Continuum International Publishing Group, 2006.
82Zigmond, AS, Snaith, RP. The Hospital Anxiety and Depression Scale. Acta Psychiatr Scand 1983; 67: 361–70.
83Cosco, TD, Doyle, F, Ward, M, McGee, H. Latent structure of the Hospital Anxiety and Depression Scale: a 10-year systematic review. J Psychosom Res 2012; 72: 180–4.
84Owen, DJ, Wood, L, Tomenson, B, Creed, F, Neilson, JP. Social stress predicts preterm birth in twin pregnancies. J Psychosom Obstet Gynaecol 2017; 38: 63–72.
85Spielberger, CD, Gorsuch, RL, Lushene, R. Manual for the State-Trait Anxiety Inventory. Consulting Pyschologists Press, 1970.
86Spielberger, CD, Gorsuch, RL, Lushene, R, Vagge, PR, Jacobs, GA. Manual for the State-Trait Anxiety Inventory. Consulting Psychologists Press, 1983.
87Sheehan, DV, Lecrubier, Y, Harnett-Sheehan, K, Amorim, P, Janavs, J, Weiller, E, et al. The Mini International Neuropsychiatric Interview (M.I.N.I.): the development and validation of a structured diagnostic psychiatric interview. J Clin Psychiatry 1998; 59: 22–33.
88Kessler, RC, Üstün, TB. The World Mental Health (WMH) Survey Initiative version of the World Health Organization (WHO) Composite International Diagnostic Interview (CIDI). Int J Methods Psychiatr Res 2004; 13: 93–121.
89Li, Y, Baser, R. Using R and WinBUGS to fit a generalized partial credit model for developing and evaluating patient-reported outcomes assessments. Stat Med 2012; 31: 2010–26.
90Gladstone, GL, Parker, GB, Mitchell, PB, Malhi, GS, Wilhelm, KA, Austin, MP. A Brief Measure of Worry Severity (BMWS): personality and clinical correlates of severe worriers. J Anxiety Disord 2005; 19: 877–92.
91Cuijpers, P, Sijbrandij, M, Koole, S, Huibers, M, Berking, M, Andersson, G. Psychological treatment of generalized anxiety disorder: a meta-analysis. Clin Psychol Rev 2014; 34: 130–40.
92Derogatis, L. SCL-90-R. Administration, Scoring and Procedures Manual for the Revised Version of the SCL-90. John Hopkins University Press, 1977.
93Heimstad, R, Dahloe, R, Laache, I, Skogvoll, E, Schei, B. Fear of childbirth and history of abuse: implications for pregnancy and delivery. Acta Obstet Gynecol Scand 2006; 85: 435–40.
94Van den Bergh, B. The influence of maternal emotions during pregnancy on fetal and neonatal behavior. J Prenat Perinat Psychol Health 1991; 5: 119–30.
95Craske, M, Rauch, S, Ursano, R, Prenoveau, J, Pine, D, Zinbarg, R. What is an anxiety disorder? Depress Anxiety 2009; 26: 1066–85.
96Clark, LA, Watson, D. Tripartite model of anxiety and depression: psychometric evidence and taxonomic implications. J Abnorm Psychol 1991; 100: 316–36.
97Gunay, EY, Gul, A. Reliability and validity of the Cambridge Worry Scale in pregnant Turkish women. Midwifery 2015; 31: 359–64.
98Takegata, M, Haruna, M, Matsuzaki, M, Shiraishi, M, Murayama, R, Okano, T, et al. Translation and validation of the Japanese version of the Wijma Delivery Expectancy/Experience Questionnaire version A. Nurs Health Sci 2013; 15: 326–32.
99Gavin, N, Meltzer-Brody, S, Glover, V, Gaynes, BN. Is population-based identification of perinatal depression and anxiety desirable?: A public health perspective on the Perinatal Depression Care Continuum. In Identifying Perinatal Depression and Anxiety (eds Milgrom, J and Gemmill, AW): 11–31. John Wiley & Sons, 2015.
101Bauer, A, Parsonage, M, Knapp, M, Iemmi, V, Adelaya, B. Costs of Perinatal Mental Health Problems. London School of Economics and Political Science, 2014.
102Biaggi, A, Conroy, S, Pawlby, S, Pariante, CM. Identifying the women at risk of antenatal anxiety and depression: a systematic review. J Affect Disord 2016; 191: 62–77.
103Davis, EP, Sandman, CA. Prenatal psychobiological predictors of anxiety risk in preadolescent children. Psychoneuroendocrinology 2012; 37: 1224–33.
104Marchesi, C, Ossola, P, Amerio, A, Daniel, BD, Tonna, M, De Panfilis, C. Clinical management of perinatal anxiety disorders: a systematic review. J Affect Disord 2016; 190: 543–50.