How effective are contraceptives?
In the chart you can see the failure rates of various contraceptives when they are used for one year. So if couples use only condoms 12 out of 100 will be pregnant after a year.
The further down the list the more reliable the method.
As you can see ‘Double Dutch’ is very safe. Not only are you very well protected against unwanted pregnancy, but also against STD’s.

                                                           Lowest expected     Typical

No contraception                                            85%                85%
Calendar Method                                              9%                40%
Withdrawal Method                                                                20%
Diaphragm                                                        5%                18%
Condom                                                           2%                12%
Birth Control Pills                                            0,1%                 3%
Nuvaring                                                         0,4%                  ?
IUD                                                                0,6%               0,8%
Hormonal implant                                            0,2%               0,2%
Female sterilisation                                          0,2%               0,4%
Double Dutch                                                  <0,1%             0,4%
Depo-Provera                                                 0,3%               0,3%
Mirena                                                            <0,2%             <0,2%
Vasectomy                                                      0,1%               0,15%
No sex                                                              0%                  0%

< means 'less than'

NB.: ONLY CONDOMS PROTECT YOU AGAINST STD’S