Please see the official leave of absence policy here: https://catalog.upenn.edu/pennbook/phdstudentleaveofabsence/
For family leave (FMLA), please see here: https://catalog.upenn.edu/pennbook/family-friendly-policies-phd-students/ Note that students must submit a form before any action can be taken.
For information regarding the Penn Student Insurance Plan (PSIP) while on leave, see: https://provost.upenn.edu/covering-psip-phd-students-medical-or-family-leave