Improving Information on Maternal Medication Use by Linking Prescription Data to Congenital Anomaly Registers: A EUROmediCAT Study

Introduction Research on associations between medication
use during pregnancy and congenital anomalies is
significative for assessing the safe use of a medicine in
pregnancy. Congenital anomaly (CA) registries do not have
optimal information on medicine exposure, in contrast to
prescription databases. Linkage of prescription databases to
the CA registries is a potentially effective method of
obtaining accurate information on medicine use in pregnancies
and the risk of congenital anomalies.
Methods We linked data from primary care and prescription
databases to five European Surveillance of Congenital
Anomalies (EUROCAT) CA registries. The linkage
was evaluated by looking at linkage rate, characteristics of
linked and non-linked cases, first trimester exposure rates
for six groups of medicines according to the prescription
data and information on medication use registered in the
CA databases, and agreement of exposure.
Results Of the 52,619 cases registered in the CA databases,
26,552 could be linked. The linkage rate varied
between registries over time and by type of birth. The first
trimester exposure rates and the agreements between the
databases varied for the different medicine groups. Information
on anti-epileptic drugs and insulins and analogue
medicine use recorded by CA registries was of good
quality. For selective serotonin reuptake inhibitors, antiasthmatics,
antibacterials for systemic use, and gonadotropins
and other ovulation stimulants, the recorded information
was less complete.
Conclusion Linkage of primary care or prescription
databases to CA registries improved the quality of information
on maternal use of medicines in pregnancy, especially
for medicine groups that are less fully registered in
CA registries.