Hi Chloe, It is recommended to sterilise once per day (at least) for newborn to 6 months. Once baby start solid food, you can reduce the frequency to alternate days. When they gets older about 1 yo, sterilisation do not need anymore. For my case, I still sterilise bottles everyday (once) because I am so used to doing it. LOL. My lo is already 35 months old. Hehe
Typically, hot water, soap and some scrubbing is sufficient to help clean the bottles. If you have a sterilizer, it is quite convenient and most of my friends use those after each feed. According to one of my friends, her doctor recommended that the most important time to sterilizer a bottle is when it is newly bought, before the first use.
It is recommended to sterilise the bottles once a day and rinse with hot water thereafter. You can gradually reduce sterilising once baby starts solid food as the bowls and spoons can't be sterilised. I stopped sterilising altogether now, baby is 7 months.
thanks