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Background and Objective: H1N1 infection carries an increased risk in pregnancy. Our aim was to study the fetomaternal outcome and the effect of early initiation of therapy.
Methods: This is a retrospective descriptive study. Confirmed infected cases were included. Maternal age, parity, gestational age at diagnosis, presenting symptoms, time between presentation and starting therapy, ICU admission, and maternal and perinatal outcome were evaluated.
Results: Nineteen confirmed patients were included. Most patients are 31 years old or more. Multiparous patients were 73.68% and 57.89% were in the third trimester. Most of our patients presented with cough, fever, and chills. Two patients were admitted to the ICU. One of them was a case of maternal mortality. 42.10% of patients were started on therapy only one day after clinical onset of symptoms. 26.31% delivered before 37 completed weeks. 73.68% delivered beyond term. Around one third delivered vaginally. 45% of babies weighed more than 3 kg. Four babies weighed less than 2 kg. Ninety percent had APGAR scores more than 8 at 1 and 5 minutes after delivery. Twenty five percent were admitted to the NICU with no neonatal mortalities.
Conclusions: H1N1 influenza A infection in pregnancy is associated with adverse maternal and perinatal outcomes. Medical and public awareness, low threshold for testing suspected pregnant patients, very early initiation of antiviral therapy, and multidisciplinary approach in our series decreased the overall adverse effects of this infection.
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 Collignon P. Swine flu—lessons learnt in Australia; Med J Aust; 2010. pp. 364–5.
 Kelly HA. A pandemic response to a disease of predominantly seasonal intensity; Med J Aust; 2010. pp. 81–3
 Australian influenza surveillance summary report no. 26, 2009, reporting period: 31 October 2009–6 November 2009
 Jamieson DJ, Honein MA, Rasmussen SA, Williams JL, Swerdlow DL, Biggerstaff MS, Lindstrom S, Louie JK, Christ CM, Bohm SR, Fonseca VP, Ritger KA, Kuhles DJ, Eggers P, Bruce H, Davidson HA, Lutterloh E, Harris ML, Burke C, Cocoros N, Finelli L, MacFarlane KF, Shu B, Olsen SJ. Novel Influenza A (H1N1) Pregnancy Working Group. H1N1 2009 influenza virus infection during pregnancy in the USA. Lancet. 2009 Aug 8; 374(9688):451–8.
 New South Wales public health network Progression and impact of the first winter wave of the 2009 pandemic H1N1 influenza in New South Wales, Australia. Euro Surveill. 2009; 14(42):pii?=?19365
 Lindsay L, Jackson LA, Savitz DA. Community influenza activity and risk of acute influenza like illness episode among healthy unvaccinated pregnant and postpartum women. A J Epidemiol 2006;163:838-848
 Lim Boon H, Mahmood Tahir AJ. Influenza A H1N1 2009 (swine flu) and pregnancy. Obstet Gynecol India 2011; 61(4):386-393.
 Kumar A, Zarychanski R, Pinto R, Cook DJ, Marshall J, Lacroix J, et al. Critically ill patients with 2009 influenza A (H1N1) infection in Canada. JAMA 2009;302:1872-1879.
 Louie JK, Acosta M, Jamieson DJ, Honein MA. Severe 2009 H1N1 influenza in pregnant and postpartum women in California . N Engl J Med 2010; 262:27-35.
 Mertz, D., Kim, T. H., Johnstone, J., Lam, P. P., Science, M., Kuster, S. P., Fadel, S. A., Tran, D., Fernandez, E., Bhatnagar, N., Loeb, M. (2014). Populations at risk for severe or complicated Avian Influenza H5N1: a systematic review and meta-analysis. PloS one, 9(3), e89697. doi:10.1371/journal.pone.0089697
 Prabhu T.R. H1N1 influenza virus infection in pregnancy: A study of 32 cases. Journal of SAFOG 2014;6(2):93-97.
 Brabin B.J. Epidemiology of infection in pregnancy. Rev. Infect. Dis.1985;7:579-603
 Goodnight WH, Soper DE. Pneumonia in pregnancy. Crit Care Med. 2005; 33(10 Suppl):S390-7.
 Jamieson DJ, Theiler RN, Rasmussen SA. Emerging infections and pregnancy. Infect Dis. 2006 Nov; 12(11):1638-43.
 Hewagama S, Walker SP, Stuart RL, Gordon C, Johnson PDR, Friedman ND, O’ Reilly M, Cheng AC, Giles ML. 2009 H1N1 influenza A and pregnancy outcome in Victoria, Australia. Clin Infect. Diseases 2010; 50:686-690.
 Liu L, Zhang RF, Lu HZ, Lu SH, Huang Q, Xiong YY, Xi XH, Zhang ZY. Sixty-two severe and critical patients with 2009 influenza A (H1N1) in Shanghai, China. Chin Med J (Engl) 2011; 124(11):1662-1666
 Meijer WJ, van Noortwijk AG, Bruinse HW, Wensing AM. Influenza virus infection in pregnancy: a review. Acta Obstet Gynecol Scand 2015; 94(8):797-819.
 Hiba V, Chowers M, Levi-Vinograd I, Rubinovitch B, Leibovici L, Paul M. Benefit of early treatment with Oseltamivir in hospitalized patients with documented 2009 influenza A (H1N1): a retrospective cohort study. J Antimicrob Chemother 2011; 66(5):1150-1155
 Viasus D, Pano-Pardo JR, Pachon J, Riera M, Lopez-Medrano F, Paveras A, et al. Timing of Osetlamivir administration and outcomes in hospitalized adult patients with pandemic 2009 influenza A (H1N1) virus infection. Chest 2011; 140(4):1025-1032.
 Higuera Iglesias AL, Kudo K, Manabe T, Corcho Berdugo AE, Corrales Baeza A, Alfaro Ramos L, et al. Reducing recurrence and severity of pneumonia due to pandemic H1N1 2009 by early oseltamivir administration: a retrospective study in Mexico. PLoS One. 2011; 6(7):e21838. doi: 10.1371/journal.pone.0021838. Epub 2011 Jul 8.
 Mertz D, Geraci J, Winkup J, Gessner B D, Ortiz J R, Loeb M. Pregnancy as a risk factor for severe outcomes from influenza virus infection: A systematic review and meta-analysis of observational studies. Vaccine 2017; 35(4):421-428.
 Siston AM, Rasmussen SA, Honein MA, Fry AM, Seib K, Callaghan WM, et al. Pandemic 2009 influenza A (H1N1) virus illness among pregnant women in the United States. JAMA 2010; 303(15):1517-1527.
 Dawood FS, Luliano AD, Reed C, Meltzer MI, Shay DK, Cheng PY, et al. Estimated global mortality associated with the first 12 months of 2009 pandemic influenza A H1N1 virus circulation: a modelling study. Lancet Infect Dis.2012; 12(9):687-695
 ANZIC influenza Investigators., Webb SA, Pettila V, Seppelt I, Bellomo R, Bailey M, Cooper DJ, et al. Critical care services and 2009 H1N1 influenza in Australia and New Zealand Engl J Med. 2009; 361(20):1925-34.
 The ANZIC Influenza Investigators. Critical care services and the H1N1 (2009) influenza epidemic in Australia and New Zealand in 2010: the impact of the second winter epidemic. Crit care 2011; 15(3):R143.
 Viasus D, Paño-Pardo JR, Pachón J, Campins A, López-Medrano F, Villoslada A, Fariñas MC, Moreno A, Rodríguez-Baño J, Oteo JA, Martínez-Montauti J, Torre-Cisneros J, Segura F, Gudiol F, Carratalà J. Factors associated with severe disease in hospitalized adults with pandemic (H1N1) 2009 in Spain. Clin Microbiol Infect 2011; 17(5):738-746.
 Changchang Li Zhijiang Liang, Michael S Bloom, Qiong Wang, Xiaoting Shen, Huanhuan Zhang, Suhan Wang, Weigin Chen, Yan Lin, Qingguo Zhao, Cunrui Huang. Temporal trends of preterm birth in Shenzhen, China: a retrospective study. Reprod Health 2018; 15:47
 Pierce M, Kurinczuk JJ, Spark P, Brocklehurst P, Knight M; UKOSS. Perinatal outcomes after maternal 2009/H1N1 infection: national cohort study. BMJ 2011; 14:342:d3214. doi: 10.1136/bmj.d3214.
 Fell DB, Savitz DA, Kramer MS, Gessner BD, Katz MA, Knight M, Luteijn JM, Marshall H, Bhat N, Gravett MG, Skidmore B, Ortiz JR. maternal influenza and birth outcomes: systematic review of comparative studies. BJOG 2017; 124(1):48-59
 William L Callaghan, Andreea A Creanga, Denise Jamieson. Pregnancy-related mortality resulting from influenza in the United States during the 2009-2010 Pandemic. Obstet Gynecol 2015; 126(3):486-490.
 Maternal and infant outcomes among severely ill pregnant and postpartum women with 2009 pandemic influenza A (H1N1)--United States, April 2009-August 2010. MMWR Morb Mortal Wkly Rep. 2011; 60(35):1193-6(ISSN: 1545-861X)
 Doll Mk, Winters N, Boikos C, Kraicer-Melamed H, Gore G, Quach C. Safety and effectiveness of neuraminidase inhibitors for influenza treatment, prophylaxis, and outlook control: a systematic review of systematic reviews and/or meta-analysis. J Antimicrob Chemother 2017; 72(11):2990-3007
 Centres for Disease Control and Prevention. What pregnant women should know aboutH1N1 (formerly called swine flu) virus. http://www.cdc.gov/h1n1fl u/guidance/pregnant.htm (accessed May 27, 2009).
 Graner S et al. Neuraminidase inhibitors during pregnancy and risk of adverse neonatal outcomes and congenital malformations: Population based European register study. BMJ 2017 Feb 28; 356:j629.
 Tanaka T, Nakajima K, Murashima A, Garcia-Bournissen F, Koren G, Ito S. Safety of neuraminidase inhibitors against novel influenza A (H1N1) in pregnant and breastfeeding women. CMAJ?: Canadian Medical Association Journal. 2009; 181(1-2):55-58. doi:10.1503/cmaj.090866.
 Ehrenstein V, Kristensen NR, Monz BU, Clinch B, Kenwright A, Sorensen HT. Oseltamivir in pregnancy and birth outcomes. BMC Infect Dis. 2018; 18(1):519
 Svensson T, Granath F, Stephansson O, Kieler H. Birth outcomes among women exposed to neuraminidase inhibitors during pregnancy. Pharmacoepidemiol Drug Saf. 2011; 20(10):1030-4.
 Steinhoff M. C., Omer S. B. A review of fetal and infant protection associated with antenatal influenza immunization. AJOG 2012; S21-S27
 Steinhoff MC, Omer SB, Roy E, Arifeen SE, Raqib R, Dodd C, Breiman RF, Zaman K. “Neonatal outcomes after influenza immunization during pregnancy: a randomized controlled trial,” Canadian Medical Association Journal, vol. 184, no. 6, pp. 645–653, 2012.
 Zaman K, Roy E, Arifeen S. E, Rahman M, Raqib R, Wilson E, Omer SB, Shahid NS, Breiman RF, Steinhoff MC. Effectiveness of maternal influenza immunization in mothers and infants. N Engl J Med 2008; 359(15):1555-1564.
 Thompson MG, Kwong JC, Regan AK, Katz MA, Drews SJ, Azziz-Baumgartner E, et al. Influenza Vaccine Effectiveness in Preventing Influenza-associated Hospitalizations During Pregnancy: A Multi-country Retrospective Test Negative Design Study, 2010-2016.Clin Infect Dis. 2018 Oct 11. doi: 10.1093/cid/ciy737.42]
[43[ Soydinc HE, Celen MK, Yildiz B, Sak ME, Evsen MS, Gul T. Pregnancy and H1N1 infection in Southeast Turkey. J Infect Dev Ctries 2012; 6(8):644-649
 Bogers H, Bos D, Schoenmakers S, Duvekot JJ. Postpandemic Influenza A/H1N1pdm09 is still Causing Severe Perinatal Complications. Mediterr J Hematol Infect Dis. 2015;7(1):e2015007.