The narrator claims that she owes her life to her mother three times. More precisely, she says she owes her "existence" to her mother based on three events. The first is during the trapeze accident. Her mother has a chance to grab her husband's ankle as they are falling but decides, in mid air, to protect herself and her unborn child. This child was the narrator's sister who was eventually stillborn. By saving herself, rather than risking her and her unborn daughter's deaths, she stays alive. Therefore, she will be alive in order to eventually have another daughter: the narrator.
The second time the narrator credits her mother for her existence is the fact that her mother met her (the narrator's) father in the hospital. So, the two events are linked. The mother saves herself, the first husband is killed, and the mother meets her next husband in the hospital. This second husband is to be the narrator's father.
The final time is when the mother directly saves her daughter. The house catches on fire and no one can reach her daughter upstairs. Being a seasoned acrobat and trapeze artist, the mother climbs a ladder, then up the tree, and makes the "leap" to the window. As they fall toward the firemen's net, the narrator has an experience like being in the womb again:
I felt the brush of her lips and heard the beat of her heart in my ears, loud as thunder, long as the roll of drums.