In 2007, 4955 women under 20 fell pregnant. But last year there were just 2865 births to under 20-year-olds and a large majority of those were to 18- and 19-year-olds. Photo / iStock
Teen pregnancies are at their lowest in eight years and some experts think social media could be partly responsible.
Data from Statistics New Zealand has revealed the number of teenage pregnancies in New Zealand among women under 20 years old has almost halved since 2007 - the year that social media became a global phenomenon.
In 2007, 4955 women under 20 fell pregnant. But last year there were just 2865 births to under 20-year-olds and a large majority of those were to 18- and 19-year-olds.
Some researchers have credited the stark drop to better access to contraception, better sex education and better parenting.
Others, however, have suggested social media may have played a part.
A leading paediatrics expert, University of Auckland Associate Professor Simon Denny, said it was possible social media had contributed to a reduction in "risk behaviours" including teenagers having unprotected sex.
"What we have seen is this reduction and at the same time we have had this explosion in social media," Dr Denny said.
"There are some suggestions that young people are spending more time inside rather than going outside and engaging in risk behaviours but there is no hard evidence on this at this point.
"The context is that it is not just [risky sexual behaviour] that is reducing, it is all of the ... risk behaviours that you have to engage in outside of the home."
The stark reduction in teenagers using alcohol could be another factor behind the decrease in pregnancies because alcohol encouraged other risk behaviours such as unprotected sex, Dr Denny said.
"The interesting thing is that this is a global phenomenon. Everywhere you look, Australia, Ireland, the UK - all the equivalent OECD countries are seeing the same drop in youth risk behaviours."
Everywhere you look, Australia, Ireland, the UK - all the equivalent OECD countries are seeing the same drop in youth risk behaviours.
According to Britain's Telegraph newspaper, researchers have recorded similar trends in countries such as England and Wales, where the number of teenage pregnancies among girls under 18 had almost halved since social media became a global phenomenon in 2007.
They reported teenage pregnancies in England and Wales had dropped by 46 per cent since 2007 and were now at the lowest level since records began almost 50 years ago.
An economist at Nottingham University Business School, Professor David Paton, who was among the first to suggest social media had an effect on pregnancies, told the Telegraph the timing was fitting.
"People [appear to be] spending time at home - rather than sitting at bus stops with a bottle of vodka they are doing it remotely with their friends," he said.
But, "nobody really knows why we've got this sudden change around about 2007 to 2008".
Before 2007, teen pregnancies in New Zealand were decreasing.
However, the number spiked in 2008 before rapidly decreasing to record low numbers in 2015.
Rates of teenage pregnancy in New Zealand (18.7 per 1000 population) is far lower than the United States (24.2) and United Kingdom (23.3), but higher than Australia (13).