I'm a first year student at mcmaster and I want to switch from social sciences to midwifery. I was wondering if there was anything I could do during the summer and next year to help me make the switch. And am I even able to make this kind of switch? There are some courses that I cannot take because I am not registered in the midwifery program. Can anyone give me some advice?

You should speak with an academic advisor, and/or someone who works in admissions for midwifery.