Gwinyai Masukume1,2, Sinéad M O'Neill2, Ali S Khashan3,2, Louise C Kenny2, Victor Grech4. 1. Gravida: National Centre for Growth & Development, University of Auckland, Auckland, New Zealand. 2. Irish Centre for Fetal and Neonatal Translational Research (INFANT), Department of Obstetrics and Gynaecology, University College Cork, Cork, Ireland. 3. Department of Epidemiology and Public Health, University College Cork, Cork, Ireland. 4. Academic Department of Paediatrics, Medical School, Mater Dei Hospital, Malta. victor.e.grech@gov.mt.
Abstract
AIM: The live birth sex ratio is defined as male/total births (M/F). Terrorist attacks have been associated with a transient decline in M/F 3-5 months later with an excess of male losses in ongoing pregnancies. The early 21st century is replete with religious/politically instigated attacks. This study estimated the pooled effect size between exposure to attacks and M/F. Registration number CRD42016041220. METHODS: PubMed and Scopus were searched for ecological studies that evaluated the relationship between terrorist attacks from 1/1/2000 to 16/6/2016 and M/F. An overall pooled odds ratio (OR) for the main outcome was generated using the generic inverse variance method. RESULTS: Five studies were included: 2011 Norway attacks; 2012 Sandy Hook Elementary School shooting; 2001 September 11 attacks; 2004 Madrid and 2005 London bombings. OR at 0.97 95% CI (0.94-1.00) (I2 = 63%) showed a small statistically significant 3% decline in the odds (p = 0.03) of having a male live birth 3-5 months later. For lone wolf attacks there was a 10% reduction, OR 0.90 95% CI (0.86-0.95) (p = 0.0001). CONCLUSION: Terrorist (especially lone wolf) attacks were significantly associated with reduced odds of having a live male birth. Pregnancy loss remains an important Public Health challenge. Systematic reviews and meta-analyses considering other calamities are warranted.
AIM: The live birth sex ratio is defined as male/total births (M/F). Terrorist attacks have been associated with a transient decline in M/F 3-5 months later with an excess of male losses in ongoing pregnancies. The early 21st century is replete with religious/politically instigated attacks. This study estimated the pooled effect size between exposure to attacks and M/F. Registration number CRD42016041220. METHODS: PubMed and Scopus were searched for ecological studies that evaluated the relationship between terrorist attacks from 1/1/2000 to 16/6/2016 and M/F. An overall pooled odds ratio (OR) for the main outcome was generated using the generic inverse variance method. RESULTS: Five studies were included: 2011 Norway attacks; 2012 Sandy Hook Elementary School shooting; 2001 September 11 attacks; 2004 Madrid and 2005 London bombings. OR at 0.97 95% CI (0.94-1.00) (I2 = 63%) showed a small statistically significant 3% decline in the odds (p = 0.03) of having a male live birth 3-5 months later. For lone wolf attacks there was a 10% reduction, OR 0.90 95% CI (0.86-0.95) (p = 0.0001). CONCLUSION: Terrorist (especially lone wolf) attacks were significantly associated with reduced odds of having a live male birth. Pregnancy loss remains an important Public Health challenge. Systematic reviews and meta-analyses considering other calamities are warranted.
Entities:
Keywords:
miscarriage; population stress; pregnancy; sex ratio; stillbirth