IBOP, chotchinga chamkati chapamwamba chapamwamba, chimatchedwanso tambala wapamwamba kwambiri. Pobowola mafuta ndi gasi, kuphulitsa ndi ngozi yomwe anthu safuna kuwona pachobowola chilichonse. Chifukwa zimayika pachiwopsezo chitetezo chaumwini ndi katundu wa ogwira ntchito kubowola ndikubweretsa kuwonongeka kwa chilengedwe. Nthawi zambiri, madzi othamanga kwambiri (zamadzimadzi kapena gasi), makamaka gasi wokhala ndi matope ndi miyala, amatulutsidwa pachitsime pamadzi othamanga kwambiri, zomwe zimapangitsa kuti pakhale phokoso lowopsa la zowombera moto. Chiyambi cha ngoziyi chimachokera ku madzi omwe ali pakati pa miyala ya pansi pa nthaka,