Abstract: In Belgium, pertussis vaccination is recommended for all pregnant women in every pregnancy. Adults in close contact with young infants are equally advised to receive a pertussis containing booster dose. Maternal influenza vaccination is likewise recommended in Belgium in the second or third trimester of pregnancy, within the influenza season. A quantitative multicenter survey study has been performed between October 2014 and May 2015 in both postpartum women (N = 823, response rate = 89.2%) and health care workers (HCWs) (N = 261) to assess the coverage of both vaccines during pregnancy along with the coverage of the pertussis cocoon strategy, and to evaluate the knowledge and recommending attitude of HCWs towards the maternal vaccination strategies and the cocoon strategy among surveyed women and HCWs. Overall coverage of pertussis vaccination during pregnancy was 64.0%. Most women were vaccinated by their general practitioner (GP) (82.4%), and most often in the third trimester (74.0%) of pregnancy. Overall coverage of influenza vaccination during pregnancy was 45.0%. Again the GP administered most vaccines (67.6%); vaccines were equally administered in the second or third trimester of pregnancy. Educational level had a significant influence on both the pertussis and influenza vaccination coverage during pregnancy while working situation and parity had only an influence on the maternal pertussis vaccination coverage and country of birth only on the maternal influenza vaccination coverage. Overall, 78.4% of gynecologists and GPs recommends both maternal pertussis and influenza vaccination and 67.0% recommends both maternal vaccination strategies and the cocoon strategy. Within the group of the midwives, only 23.7% recommends both maternal pertussis and influenza vaccination and 10.5% recommends both maternal vaccination strategies and the cocoon strategy. High coverage is reached among pregnant women for pertussis and influenza vaccination. Several underserved populations of pregnant women regarding ...