TY  - JOUR
T1  - RIsk of birth defects after use of acyclovir, valacyclovir, and famciclovir in the first trimester—reply
AU  - Pasternak B, Hviid A
Y1  - 2010/11/24
N1  - 10.1001/jama.2010.1702
JO  - JAMA
SP  - 2242
EP  - 2243
VL  - 304
IS  - 20
N2  - 
In view of the difficulties in performing studies of drug safety in pregnancy because of the relative rarity of both exposure and outcome, the use of nationwide registry data allows the identification of a sufficient number of exposed pregnancies to reach adequate power, at least for birth defects in aggregate. Furthermore, antivirals are prescribed for acute infections, and women who filled prescriptions for these drugs are therefore more likely to have used the drugs compared with (as an example) those who filled prescriptions for drugs prescribed for prophylactic indications. Moreover, people who fill prescriptions for drugs seem very likely to have used them since they have traveled to a pharmacy and purchased the drugs.

SN  - 0098-7484
M3  - doi: 10.1001/jama.2010.1702
UR  - http://dx.doi.org/10.1001/jama.2010.1702
ER  -