Figures out today from the children's charity, the ISPCC, show that three in every five calls to Childline went unanswered last year because of a shortage of people staffing the service.
In total, more than 240,000 calls were answered in 2006, representing a 16% increase on the previous year.
These annual statistics show that a total of 640,000 calls were made to Childline last year, of which 40% were answered.
16% of calls were about sexual issues, 4% concerned pregnancy, and another 4% were about sexual abuse.
The service also received over 10,000 text messages. The majority of these queries were to do with issues concerning pregnancy.
The Childline website received over 11,000 hits, according to the figures.
The Chief Executive of the ISPCC, Paul Gilligan, said awareness of child welfare has never been greater and that Childline, which has expanded its services in recent years, was reliant primarily on the work of volunteers.