The polar bear reproduction process is complicated, involving delayed implantation
, meaning that the embryo takes four to eight months to implant.
As a result of this delayed implantation
, the female is technically pregnant for at least 6 months.
is a special reproductive strategy of the giant panda (Zhang et al.
Penile prosthesis insertion in patients with refractory ischaemic priapism: early vs delayed implantation
. BJU Int 2014; 114: 576-81.
This is an example of delayed implantation
. That means the fertilized egg divided only a few times and then the growth is put on hold for quite some time.
Methods: The pregnant mice were ovariectomized on the evening on the third day of pregnancy with a single injection of medroxyprogesterone acetate to induce delayed implantation
Female polar bears only release an egg after mating and they practise delayed implantation
, where the egg does not implant into the uterine wall until some months later.
(7) When considering the right timing for implants placement, there are two reasons in favor of the delayed implantation
. The first is in the fact that the successful osseointegration depends on osteoblasts capable for osteogenesis, and another reason is that the simultaneous implantation is proportionally more demanding and rarely meets prosthetic requirements.
The reproductive cycle of the river otter involves embryonic diapause or delayed implantation
of embryos (Renfree and Shaw, 2000; Melquist et al., 2003).
Bats have evolved various reproductive strategies such as delayed sperm maturation sperm storage delayed fertilization delayed implantation
and delayed development.
The gestation period for a panda ranges from 95 to 160 days and successfully predicting the due date is further complicated by a phenomenon known as delayed implantation