Many vaccines require more than one dose to give long lasting protection. Vaccines such as whooping cough (pertussis) are given as early as possible to protect babies at a time when they are very vulnerable. By the time your child is 4 years old they will have had 4 doses of this vaccine given at 8, 12 and 16 weeks and at 3 years 4 months.
Rydym yn croesawu gohebiaeth a galwadau ffôn yn y Gymraeg neu'r Saesneg. Atebir gohebiaeth Gymraeg yn y Gymraeg, ac ni fydd hyn yn arwain at oedi. Mae’r dudalen hon ar gael yn Gymraeg drwy bwyso’r botwm ar y dde ar frig y dudalen.
We welcome correspondence and telephone calls in Welsh or English. Welsh language correspondence will be replied to in Welsh, and this will not lead to a delay. This page is available in Welsh by clicking ‘Cymraeg’ at the top right of this page.