PT - JOURNAL ARTICLE AU - , AU - , AU - , TI - Number of births to maintain competence. DP - 2002 Apr 01 TA - Canadian Family Physician PG - 751--751 VI - 48 IP - 4 4099 - http://www.cfp.ca/content/48/4/751.short 4100 - http://www.cfp.ca/content/48/4/751.full SO - Can Fam Physician2002 Apr 01; 48