<s>[INST] Hi I am 21years old and have been on depo provera for 4years, I have not gone back for my next injection due to wanting to concieve. I havnt had a period since I ve been on this birth control , can I still get pregnant without a period? Also my endometrium lining is 4mm thick is this bad? I ve heard bad things about this drug because of my age do I have a good chance of concieving? [/INST] Hi, Depo provera is unique injectable longacting contraceptive which usually act for 3 months duration, but in many women on depo provera menstruation may stop during and after injection, usually after use for more than 1 year. peroids usually returns to normal after stopage. menstruation depends on ovulation which is stoped during depo provera contraceptive, and pregnancy is depends on ovulation so if you continue to have amenorrhea or lack of peroids consult your gynecologist, and as your age is just 21 years dont worry and hurry for pregnancy. take care </s>