Hello, and I hope I can help you today.
Errin is actually a pill that contains only
progesterone. You need to take a pill every day of the month for it to work. Alone, the Errin pill is about 90 percent effective in preventing
pregnancy, so if you always use a condom you are very safe from pregnancy.
If you started the pills over a month ago, you need not to worry about an error in taking the pill from last month. As long as you use condoms too, you are very well protected against pregnancy. Progesterone-only pills are generally not recommended as a primary form of birth control (alone with no backup method) unless you are
breastfeeding, where the breastfeeding hormone also provides some protection.
If you decide to have unprotected sex, a combined (both
estrogen and progesterone) pill is more effective (over 99%) than the "mini" pill.
I hope I answered your question adequately today and that this information was reassuring.
Best wishes, Dr. Brown