The baby sloth after delivery. (Sam Trull)

Last week, a team of vets in Costa Rica performed what may be the first ever Caesarean operation on a sloth in an attempt to save an injured mother and her pre-term baby. Unfortunately, both mother and baby have since died.

The pregnant sloth was brought to the Kids Saving The Rainforest wildlife rescue clinic after falling from a tree at a local hotel. According to Sam Trull, wildlife manager of the clinic, the animal suffered from seizures — indicating she'd injured her brain — but didn't have a fractured skull, giving Trull hope for her recovery.

Unfortunately, the sloth was also pregnant. Soon she started having contractions, but showed no signs that she'd be able to give birth.


An ultrasound was performed on the mother to check the baby sloth's status. (Sam Trull)

Trull took the sloth to a veterinarian in Herradura, but the news was bad: The baby was coming feet first, and the mother had a full bladder. A full bladder might not sound like a major issue, but sloths can hold as much as a third of their body weight in urine and feces. They empty that cache rarely, in a slow process that involves something resembling a dance (see below).

So with a full bladder that was unlikely to empty on its own, the vets knew that the baby would never have the room it needed to turn into position for the birth. From the BBC:

The operation was performed on 1 October. After consulting a senior colleague by phone, the vet gave the sloth a general anaesthetic and called in two assistants to help. First the vet drained the swollen bladder, then cut into the womb. After a procedure of around 30 minutes, the baby's head emerged.

To warm the cold preemie, Trull held the infant against her chest — a method used to warm up hypothermic human babies.

While the delivery itself was a success, the baby showed heart, lung and feeding problems and died a week later. The mother died the next day of a stroke. You can read more (and see more amazing photos of the surgery) on Trull's blog.


Doctors locate the uterus and lift the baby out. (Sam Trull)

Baby tries to breathe. (Sam Trull)

Doctors work quickly to remove any fetal fluids restricting the baby’s airway. (Sam Trull)

Troll holds baby immediately after surgery to increase sloth's body temperature. This method is called “skin to skin” and is used in human babies as a quick and effective way to reverse hypothermia which is a common complication in c-section births.

Mother and child two days after surgery. Both died within a week. (Sam Trull)