1. An ergonomic baby carrier has a wide waist belt, that distributes baby's weight between parent's shoulders and hips. Kangaroos don't have such a waist belt, all baby weight goes to mother's shoulders and causes backache.
2. An Ergonomic baby carrier has long wide thick shoulder straps that evenly distribute baby weight. Kangaroos' shoulder straps are narrow and dig into mother's shoulders.
3. The back of the ergonomic baby carrier is wide in the area where it joins the waist belt. The wide carrier back allows the baby to sit physiologically, with widely spread legs and good under-knee support. Position of baby's legs in the kangaroo carrier is NOT physiological. Kangaroos have narrow carrier backs (usually not more than 20 - 22 cm) and look like “tough underpants”. Baby's legs in kangaroo carrier hang down, knees are below the bottom or at the same line as the bottom (like symbols Λ or П). Being in kangaroo, baby "hangs" on a perineum, like a paratrooper in "underpants", all baby’s weight lies on its bottom, perineum and lower spine – that is extremely harmful and unacceptable for babies!
4. Ergonomic baby carrier has a soft back, baby is tight to mother evenly across all spinal cord. Kangaroos have a tough back construction, baby "dangles" apart from mom, similar to wearing of a heavy bag on straps.
5. A kangaroo carries a baby in a front-outward position. This is one of its major distinguishing features from ergonomic baby carriers. There is reasoned doctors' opinion that carrying a baby in this position is harmful for baby's hip joints and also for baby's psyche. Sitting in a front-outward position the baby is unable to curve his back naturally, the back is constantly in a tense position, and baby’s head has no support. During a sleep, neck muscles are relaxed; being in Kangaroo in a front-outward position baby's head just hangs down! Carrying baby with face towards world is considered harmful from psychological point of view also. Baby cannot hide from strangers' eyes, unnecessary emotions, discomfort, etc. Baby absorbs too much informational and negative emotions, this could lead to hysterics and crying before falling asleep, as baby need to relieve all his/her emotions. On the other hand, carrying baby in an ergonomic baby carrier develops baby's nervous system. Baby has eye-to-eye contact with his mother; it gives him/her better psycho-emotional development as from mothers' eyes baby learns reactions and emotions from the world around him. This gives him emotional comfort as baby feels mother's heartbeat, mother's natural body smell, look, mother's voice and breath.