China Baby
The baby that was recently rescued from a sewage pipe in China (above) is not this year's only sewer baby (Reuters)

A Japanese woman gave birth in an open toilet last week, and called firefighters after her child slipped 1.5m down the toilet. The incident happened in the country's Okayama Prefecture.

The 22-year-old mother was reportedly unaware of her pregnancy and was astonished to give birth when she went to use the squat-type toilet on Thursday morning, 6am local time. According to Japan Today, firefighters had to break through the floor in the toilet and the entire rescue operation took 90 minutes.

Fortunately, the baby was recovered unharmed. The mother suffered heavy bleeding and was taken to a hospital, where she made a full recovery.

"I felt something uncomfortable in my body. I didn't know I was pregnant," she said later.

An identical case was reported in eastern China last month when an infant boy got stuck in a sewage pipe directly beneath a toilet, which was where his mother gave birth.

Meanwhile, a 2002 study published in the British Medical Journal (BMJ) suggests the phenomenon of unknown pregnancies and deliveries is known as "denial of pregnancy" and is not uncommon.

"The common view that denied pregnancies are exotic and rare events is not valid. Deliveries in which the woman has not been aware of her pregnancy until going into labour occur about three times more often than triplets," a comment by the author, Ulrich Buscher from the University of Berlin, reads.

Japan Today's report describes denial of pregnancy as a mental condition whereby a pregnant woman, despite changes occurring to her body, convinces herself she is not pregnant. The psychological condition, in some cases, can also cause the pregnant woman to have regular menstrual-like bleeding, with no pregnancy-associated weight gain.

In 1995, a study by Anna M Spielvogel and Heidi C Hohener, from the Department of Psychiatry at the University of California, associated denial of pregnancy with psychological conflicts, claiming "... possible contribution of painful reactivation of memories concerning childhood or adult trauma and the effect of dissociative states on the development of denial of pregnancy".