Aspectos EpidemiológicosCongenital anomalies are a leading cause of perinatal mortality (according to EUROCAT’s data, it reaches
a prevalence of 9.4 per 10,000 births). Moreover, the most recent Global Burden of Disease Project estimated
that congenital anomalies in 2010 accounted for 732,000 Disability Adjusted Life Years Lost (DALYs) in
Western Europe, 274,000 in Central Europe and 898,000 in Eastern Europe. Thus, like other Rare Diseases,
congenital anomalies are individually rare but collectively a significant public health issue.
This report performed by ECEMC (the Spanish Collaborative Study of Congenital Malformations) is the
annual update of the congenital anomalies surveillance report, after having analysed data gathered by this
research programme between 1980 and 2011, although ECEMC was created in 1976. It is hospital-based and
has a case-control design. The report is based on data from 2,735,086 births surveyed, among which a total
of 40,329 presented with congenital anomalies detected during the first 3 days of life. Present coverage of the
program is 17.95% of total births in Spain. The time distribution, geographical distribution and spacialtemporal
distribution of the frequency of congenital anomalies in Spain were studied. The global frequency
of infants with congenital defects has significantly decreased along the time, from the basal frequency
registered in 1980-1985 (2.22%) to 1.03% in 2011 (Tables 1 and 3), mainly as a consequence of the impact of
terminations of pregnancy after the detection of foetal anomalies (ETOPFA), which has been legal in Spain
since the end of 1985. This tendency has also been statistically significant in 14 out of 17 Autonomous Regions
and in many participating hospitals (Table 3). Only in Extremadura (see Fig. 1) a significant increase was
detected, although the frequency registered in 2011 was not significantly different from ECEMC’s global
frequency in the same year. After applying the protocol specifically designed at ECEMC for the study of
clusters of birth defects, it was concluded that this increase was probably due to both methodological issues during the first years (with some under-registration of birth defects) and the high quality scrutiny and reporting
of newborn infants with congenital anomalies, especially in the province of Cáceres). After correcting the
frequency in the different hospitals and Autonomic regions by including ETOPFA cases and referrals to
tertiary care hospitals, little changes were observed, mainly due to the difficulties to report ETOPFA cases.
The time distribution of the frequency of 33 selected birth defects (Table 4) revealed a statistically
significant decrease for most of them, although significant increases were also detected for heart/great
vessels defects and unilateral renal agenesis, that were interpreted as a result of the availability of better
diagnostic procedures. Also, for the annual distribution of 16 selected birth defects (Graphs-1), significant
decreases were observed for all global frequencies except for anotia/microtia and gastroschisis.
Regarding the temporal-spatial analyses of the frequency of 18 selected defects (Tables 5-10), the global
decreases were also evident in many Autonomous Regions. Only an increase was detected for anencephaly
in Aragón, where no clue on a local cause for the increase was observed, and where only one case was
registered in 2011. Geographical heterogeneity could be detected in 2011 for several defects and was
attributable to the birth of a higher than expected number of cases of anencephaly in Aragón, of cleft lip in
Galicia, oesophageal atresia/stenosis in the Canary Islands, and hypospadias in Cantabria. All these clusters
were analysed and again no local cause was identified and it was concluded that possibly they are stochastic
events, although they will be maintained under close scrutiny until the next surveillance report.
Since immigration in Spain has been very remarkable in the last years, the ethnic origin of cases and
foreign extraction of their parents were analysed. A statistically significant increase along the time in the
percentage of foreign parents was detected (Graph 4), and this was more marked among cases than among
controls. Also an increase in all ethnic groups except the oriental one was observed (Graph 5). A higher risk
for congenital anomalies was observed for all the groups except the Indian group, with respect to the native
white group (Graph 6).
Some final comments are included regarding the importance of congenital anomalies registries as
infrastructure for the research on their causes and prevention, as well as on the exceptional characteristics
of ECEMC’s registry and network (including its international activities for birth defects surveillance), and the
need for more campaigns for their primary prevention and more research on their causes. In this sense, a
reference is made on Kirby and Browne’s 26 consideration of birth defects surveillance as “an essential public
health function for primary prevention and health promotion”.N
