共 70 条
[1]
ABITBOL MM, 1991, J REPROD MED, V36, P369
[2]
*AM COLL OBST GYN, 1995, VAG DEL PREV CES BIR
[3]
BEALL M, 1984, J REPROD MED, V29, P31
[8]
Cragin E, 1916, NY STATE J MED, V104, P1
[9]
*CTR DIS CONTR PRE, 1993, MMWR-MORBID MORTAL W, V42, P285
[10]
CURTIN SC, 1997, MONTHLY VITAL STAT R, V45