Titelaufnahme

Titel
Twin birth and maternal condition / Sonia Bhalotra (ISER, The University of Essex and IZA), Damian Clarke (Universidad de Santiago de Chile) ; IZA Institute of Labor Economics
VerfasserBhalotra, Sonia R. ; Clarke, Damian
KörperschaftForschungsinstitut zur Zukunft der Arbeit
ErschienenBonn, Germany : IZA Institute of Labor Economics, August 2018
Ausgabe
Elektronische Ressource
Umfang1 Online-Ressource (26, A26 Seiten) : Diagramme, Karten
SerieDiscussion paper ; no. 11742
URNurn:nbn:de:hbz:5:2-164193 
Zugriffsbeschränkung
 Das Dokument ist öffentlich zugänglich im Rahmen des deutschen Urheberrechts.
Volltexte
Twin birth and maternal condition [0.68 mb]
Links
Nachweis
Verfügbarkeit In meiner Bibliothek
Zusammenfassung

Twin births are often construed as a natural experiment in the social and natural sciences on the premise that the occurrence of twins is quasi-random. We present new populationlevel evidence that challenges this premise. Using individual data for 17 million births in 72 countries, we demonstrate that indicators of mother's health and health-related behaviours are systematically positively associated with the probability of a twin birth. The estimated associations are sizeable, evident in richer and poorer countries, evident even among women who do not use IVF, and hold for numerous different measures of health. We discuss potential mechanisms, showing evidence that favours selective miscarriage. Positive selection of women into twinning implies that estimates of impacts of fertility on parental investments and on womens labour supply that use twin births to instrument fertility will tend to be downward biased. This is pertinent given the emerging consensus that these relationships are weak. Our findings also potentially challenge the external validity of studies that rely upon twin differences.