Garudapurana 1.107.13

1.107.13

janmanā ca vipattau ca bhavetteṣāṃ ca sūtakam /
caturthe daśarātraṃ syātṣaṇṇiśāḥ puṃsi pañcame //

incur impurity both at birth and at death. / For the fourth [generation] it is ten nights; for the fifth, six nights for a man;