I'd be interested in hearing your thoughts on this topic, mama/midwife. How would you handle this if the client was not you? And then...what do you feel intuitively about your platelet count? Are you worried, or is your academic midwifery background telling you to worry? There is no judgement at all in these questions. I have simply always been interested in platelet count during pregnancy because there is so little literature out there on the topic.
As a student, I have worked with two mamas with very low platelets. At term, one mama was in the 120's (and had dropped from the 200's) and the other mama's count was 82 (had dropped from 145 in the beginning of her pregnancy). Both were concurrently seeing a hematologist who was "not worried". He put them on multiple B-12 injections in the last trimester, and both mamas' platelet counts continued to drop during their pregnancy. Increased folic acid through both diet and supplements were recommended, both clients attested to supplementing, and still both clients' platelets continued to drop.
The midwives prepared for hemorrhage with pit, methergine, and cytotec. One mama had a birth center birth, the other mama birthed at home. I believe the homebirthing mama received prophylactic pit, but I do not remember for sure. Neither hemorrhaged, so it is difficult to say whether or not the hypothetical hemorrhage would have been devastating due to the low platelet count.
So basically, in my limited experience, in mamas with falling platelet counts, nothing works to bring the numbers back up or to stall the dropping count but this may not necessarily lead to adverse birth outcomes.
I hope more midwives with more experience join in this topic! And good luck with your research, mama! 
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