My dr wrote me certificates, so I could work short days (max 4 hours) & then take personal/sick leave for the remainder of each day. This was important because if I had reduced my contract hours it would have altered the amount of mat leave & super that I was paid each week. It did get progressively worse though so I ended up taking mat leave from 32 weeks. This was in a fairly sedentary office role but I was having trouble even just walking.

The most important thing with SPD: do not push through the pain!! I saw a physio regularly & wore a tubigrip thing, had stretches to do regularly, which helped notch the pain level down from extreme to moderate.