nanogram means 1 billionth of a gram, and they probably mean per ml. This
is level of 13 ng/ml is much higher than what we would expect given the
pharmacology and other data we have available on breastfeeding and
sertraline. Maternal levels would be higher than this by a factor of 2 or 3
or more.
Perhaps this is one where you should email Tom Hale directly, to see what it
means. I'm sure he would be very interested.
Jack Newman, MD, FRCPC