The boy believed to have fathered a baby with a 12-year-old Perth girl is understood to be just 14.

Police were still investigating yesterday whether charges should be laid against either of the young parents but have said their focus was to ensure the family had appropriate support.

The child parents could be charged for engaging in sexual activity, because the law says that anyone under 16 cannot consent, but police have the discretion not to prosecute.

The Department of Communities has refused to say what will happen to the baby or whether relatives of the young parents will care for it.

In the wake of the case, a health promotion researcher has questioned whether schools should start teaching about puberty and conception from a younger age.

Sharyn Burns, from Curtin University’s school of public health, said a 12-year-old giving birth was rare.

There had been a downward trend in teenage pregnancies in recent years and young people were waiting longer, on average, before having sexual intercourse.

“It is a one-off case, we need to recognise that,” she said.

“But I think having good relationship and sexuality education in schools is always going to be a positive, because some kids may not get that experience from their parents.”

Associate Professor Burns said schools could decide when to introduce the topic of puberty, which included body changes and conception, but most WA schools did so in Year 6.

“We think it actually should be coming a little bit earlier because kids are starting to go through puberty earlier these days than they did in the past,” she said. “So probably around Year 5 is ideal.”

The average age girls started menstruation had fallen in the past 20 years, from 13 to about 11.

Associate Professor Burns said many teachers tended to “gloss over” some aspects of the relationships and sexuality curriculum because they lacked the confidence or the skills to teach it, prompting Curtin to set up a sex education training program for teachers four years ago.

“One of the issues with sex education is that in the WA curriculum there are a lot of learning outcomes that link to relationships and sexuality education, but not all schools take it up,” she said.

“And some schools will try to avoid it because teachers are not confident. It is a fairly tricky thing to teach.”

“Not all universities offer it to pre-service teachers, so a lot of teachers come out and they don’t have the skills to deliver relationship and sexuality education.”

The 12-year-old girl gave birth at home and it is understood she said she had been unaware of her pregnancy.

Associate Professor Burns said the 12-year-old girl might not have been aware of the pregnancy because at that age menstruation could be irregular.

“Not everyone is sick or feels unwell during their pregnancy,” she said. “It’s hard to speculate, there may have been some denial or it may just be ignorance of not knowing what’s happening.”

“I think the thing to come out of this is the more kids are aware of what actually happens, and that you can get pregnant the first time you have sex, they are really important messages to give kids.”