If you're breastfeeding and taking combination pills, a small amount of the hormones will be in your breastmilk, but it's unlikely these hormones will have any effect on your baby. (plannedparenthood.tumblr.com)
If you start combination pills within 5 days of when your period starts, you'll be protected from pregnancy right away. (plannedparenthood.org)
They work the same way as combination pills, causing cervical mucus to thicken and the lining of the uterus to thin, thus keeping sperm from reaching an egg. (momtricks.com)