Inauspicious body-making (Karma)- A subtype of Nāma (body-making) Karma,
the Udaya (rise) of which is responsible for getting the body with inauspicious (i.e., ugly and weak) lower portion (i.e., below the navel).
yadudayavaśāt nābheradhastanā pādādayo'vayavā aśubhā bhavanti tadaśubhanāma.
(Prajñā 23.38 Vṛ Pa 474)