TY  - JOUR
A1  - Ventura, S.
A1  - Abma, J.C.
A1  - Mosher, W.D.
A1  - Henshaw, S.
T1  - Estimated pregnancy rates for the United States, 1990-2000: An update
Y1  - 2004
JF  - National Vital Statistics Reports
VL  - 52
IS  - 23
SP  - 1
EP  - -9

ER  -