I was told they were making my role part time due to my sickness, I had taken 5 days sick leave

I was working for an HIV charity when I was pregnant. The hours were long and physical work was needed but no risk Assessment was done. I went on to miscarry. I took one day off to recover and was not paid for that day without prior warning despite having 20 paid sick days a year in my contract, none of which I’d used.
I became pregnant again 3 months later. I had terrible morning sickness but still rarely took a day off. Again no risk Assessment was performed. I was brought into a meeting at 8 weeks pregnant and told my performance was not up to par. I had been given a pay rise due to excellent performance before the first pregnancy. About a week later I was told they were making my role part time due to my sickness – at this time I had taken maybe 5 days off sick. When I questioned this I was told they might decide there isn’t a job for me at all. I found a new job at that point starting at 20 weeks pregnant. But I’m still there now 2 years later.