TY - STAND AU - H. Jick AU - J. Kaye AU - C. Vasilakis-Scaramozza AU - S. Jick BT - Bmj M1 - 7270 PY - 2000 SP - 1190 EP - 5 T2 - Bmj TI - Risk of venous thromboembolism among users of third generation oral contraceptives compared with users of oral contraceptives with levonorgestrel before and after 1995: cohort and case-control analysis VL - 321 SN - 0959-8138 (Print) 0959-8138 ER -