How to increase iron levels easily?

I am 24 1/2 weeks pregnant and just got a call from my doctor saying that my iron levels are dangerously low. I have problems with most prenatal vitamins because of the iron in them so I am now taking one without it. They told me that I needed to be taking iron pills twice a day but my body has not processed iron pills well throughout my life. This is an ongoing issue. I was told that if I took liquid chlorophyll that it would raise my iron levels but I am not sure. Any help would be appreciated.