Mobile phones and behavioural problems
This article found an association between mobile phone use in pregnancy and behavioural problems in childhood, with an additional association with the child using a mobile phone before they were 7. I was not the only one reported as being sceptical, but the study is predictably getting a lot of coverage particularly in pregnancy advisory websites.
The authors did their best with a large survey, but they admit that mobile phone use in pregnancy is associated with being poorer, younger, more stressed, smoking, and doubtless many other factors that are known to increase the risk of behavioural problems. It is difficult to tease out the effect of a single factor even using statistical adjustment methods. They also find an association between mobile phone use in children under 7, even without use by their mothers were pregnant, and behavioural problems. Such an association is unsurprising, but I am not convinced that it's the phone use that causes the problems.