Women who opt to eat their own placenta after giving birth are being warned that there are no proven health benefits linked with this, and there may even be unknown risks.

Some claim that the consumption of the placenta, known as placentophagy, helps to prevent postnatal depression and offers other health benefits, such as pain relief, increased energy and help with breastfeeding.

The placenta can be consumed raw, cooked or in capsule form.

US researchers decided to asses the potential health benefits of placentophagy. They analysed 10 reviews on this topic, which included both human and animal data.

They found no scientific evidence that consuming the placenta offered protection against postnatal depression. They also found no evidence that it offered other health benefits, such as pain relief, or that it enhanced bonding between the mother and baby.

The researchers from Northwestern University also expressed concern that there have been no studies carried out to investigate any potential risks associated with eating the placenta.

"Our sense is that women choosing placentophagy, who may otherwise be very careful about what they are putting into their bodies during pregnancy and nursing, are willing to ingest something without evidence of its benefits and, more importantly, of its potential risks to themselves and their nursing infants," said the study's lead author, Dr Cynthia Coyle.

She pointed out that there are no regulations governing how a placenta should be stored and prepared and the dosing is ‘inconsistent'.

"Women really don't know that they are ingesting," she said.

The researchers noted that while almost all mammals, aside from humans, consume their placenta after giving birth, the first documented accounts among women were in the US in the 1970s.

In recent years, it has become more popular, particularly when celebrities such as Kourtney Kardashian have done it.

"The popularity has spiked in the last few years. Our sense is that people aren't making this decision based on science or talking with physicians. Some women are making this based on media reports, blogs and websites," the researchers commented.

They called for more research on this topic.

Details of these findings are published in the journal, Archives of Women's Mental Health.

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