Plan B is considered safe for use during breastfeeding. While estrogen and progestin do pass through breast milk, the amount is not significant enough to cause any harm. Plan B should not cause any change in the quality or quantity of your breast milk supply.
If you are breastfeeding every 2-4 hours, it is unlikely, but not impossible, that you would ovulate. You may want to discuss this further with your ob/gyn doctor and consider starting a long term method of birth control.
29. January 2012
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