Introduced a bottle in the evening to try and reduce the cluster feeding, on advice of HV, and try to increase weight gain. Using aptamil formula. First few days were fine but last night and again tonight DD has thrown it all up. sounds like she's choking and then, once we've cleaned it all up, really nasally (sp?) and seems to struggle to breathe. Any ideas why she's started to do this and what we can do to prevent it? Still BF rest of the time.