Table 1.

Number of birth defects surveillance programs evaluated in this review and their main characteristics

Birth Defects surveillance networks	Number of surveillance programs	Microtia-Anotia reporting	Ascertainment	Years considered	Pregnancy outcome ascertained
EUROCAT	26	Anotia only registered	Population-based	Longest available period up to 2007	LB, SB, ETOPFA (b)
ICBDSR	39	Microtia and Anotia are differentiated (a)	Mostly population-based	Longest available period up to 2007	LB, SB, ETOPFA (c)
NBDPN	27	Microtia and Anotia are not differentiated	Population-based	2002–2006	LB, SB, ETOPFA (d)

LB = Livebirth, SB = Stillbirth, ETOPFA = Elective termination of pregnancy for fetal anomalies

^(a)Anotia and microtia are not differentiated in China CBDMN, Finland, Japan JAOG, and Mexico RYVEMCE

^(b)ETOPFA are not reported in Poland and Poland Wielkopolska

^(c)ETOPFA are not reported in Canada British Columbia, Canada National, China Beijing, China CBDMN, Italy Sicily, Japan JAOG, Spain ECEMC, and Ukraine

^(d)ETOPFA are not reported in Alaska, Arizona, Colorado, Florida, Illinois, Indiana, Kentucky, Massachusetts, Michigan, Mississippi, Nebraska, New Jersey, New York, Rhode Island, Tennessee, Virginia, and Wisconsin