Causes of Dystocia

The causes of dystocia spring from many management choices ranging from breeding genetics and nutrition to management of the cow or heifer during delivery.

• Breeding - genetics can play a role in dystocia through birth weight and heifer development.
• Over conditioned dam - too much fat around the pelvis can lead to a small birth canal.
• Malformation of the calf or the dam.
• Shortened or lengthened gestation.
• Heifers often have dystocia because the birth canal (mainly the vagina and vulva) does not stretch enough for the calf to be delivered.
• Fetal-maternal incompatibility (the fetus is too large or the cow's pelvis is too small) - most frequent cause of dystocia in beef cows/heifers.
• Malposition - infrequent cause of dystocia; occurs in less that 4% of all calvings in beef animals, but may be more frequent in dairy animals.
  
• Other diseases - i.e. Milk Fever where there is a decrease in calcium which will decrease muscle tone causing the cow to become too weak to push out the calf, or uterine torsion where the cervix is twisted.

There are many things a producer can do prior to calving that will help decrease the amount of dystocia that he/she encounters during calving. Please see Preventive Measures