The first occurrence.
To the woman He said: I will greatly multiply your pain and your travail; in pain you shall bring forth children; and your desire shall be to your husband, and he shall rule over you. Gen 3:16
The primitive root.
Strong’s H6093, itstsabon, a concrete noun meaning, “painful toil;” i.e., to be in pain from grief or heavy toil; pain, labor, hardship, sorrow, toil. It is from Strong’s H6087 עצב atsab, a primitive root meaning, “to labor.” The ancient pictographs are ayin + tsadey + bet.
ayin ע = the eye, thus to see, watch, look, know, understand
tsadey צ = trail, thus a man concealed, journey, chase, hunt
bet ב = house, thus house, household, family, in, within
The story: Looking ahead (ayin) at a lifelong journey (tsadey) to maintain the house and family (bet). The sense I am getting, in its association to pain from grief or heavy toil, is of endless work: a job that is never completed. Housework, cooking, laundry, home repairs, raising crops, tending livestock, going to a job: it is the same work over and over again constantly repeating, which continues until the man and the woman return to the dust from which they were taken.
An alternate meaning of atsav according to Gesenius’ Hebrew Lexicon, is “to worry or be vexed,” and I think that is a very common side effect of the responsibility men and women have in caring for their family.