You OB sounds like a moron. Weight gain often slows during the last months of pregnancy due to reduces stomach size/appetite. 25-35lbs is considered a normal weight gain for a women who starts pregnancy at an average weight for her size.
I also suspect that your OB is not up on the latest research which clearly shows that LOWER iron levels are normal and are in fact healthier for mom and baby. Excess iron during pregnancy negatively effects mom's immune system and can retard fetal growth. In the case of true, non-preexisting anemia often the cause is either a) too little vitamin c or b) too little protein. However of real concern is that elevated lead levels can cause anemia and lead levels should ALWAYS be checked when anemia is found. It is too simple and cheap a test, and too serious a problem to be ignored. Also excessive quantities of dairy can lower iron levels.
http://www.gentlebirth.org/archives/nutrition.html#Anemia
“One of the great unresolved issues of pregnancy is the significance of a low hematocrit/hemoglobin.
Actually, the studies are clear that lower levels are better, and the unresolved issue is why practitioners continue to encourage iron supplementation and chide women for low levels.
"Normal" values of hematocrit/hemoglobin are determined by studying non-pregnant people. However, a pregnant woman's blood volume expands around 40-60%; this blood volume expansion reduces the concentration of red blood cells and iron in her blood, which is what's measured by hematocrit and hemoglobin.
The best pregnancy outcomes are associated with the lowest hematocrit/hemoglobin. It turns out that 9.5 is optimal. This isn't because pregnant women don't need iron; it's because healthy pregnant women have large increases in blood volume that lower the hematocrit/hemoglobin.
So, in fact, a woman who's having problems with her pregnancy and doesn't have an increasing blood volume will have higher h/h levels than a healthy woman.
There are better ways of assessing anemia in pregnancy; fatigue is a clue, but the best way to assess how well your blood is carrying oxygen is to look for pallor in the gums and under eyelids and to assess capillary refill when you apply pressure to the nailbed. .
http://www.hindawi.com/GetArticle.aspx?doi=10.1155/S156536330300013X
“Despite significantly elevated hepatic iron stores after iron supplementation in pregnant rats this had no significant effect upon blood haemoglobin or transferring saturation levels. However the mean weight of the foetuses at Day 20-21 was significantly lower than that of the non-supplemented pregnant rats. Iron supplements significantly increased the activity of NADPH oxidase in the maternal alveolar macrophages, the primary event in the formation of the phagolysosome to combat invading organisms. However inducible nitric oxide synthase activity was significantly reduced in these macrophages as shown by decreases in LPSinduced and LPS+IFN,-induced NOS activation. Iron supplementation to rats of normal iron status at the commencement of pregnancy did not show any beneficial effects to either the foetus or the mother.”
Iron suppleme.ntation of pregnant individuals with adequate iron status may aggravate oxidative stress [Lachili et al., 2001], with the potential for oxidation of lipids and DNA [Schill and Reilly
2000], a factor which could contribute to preterm delivery,
Iron supplements to rats which have normal iron status at the commencement of pregnancy appear to induce toxicity in both the mother- a reduced immune function as well as to the offspring- reduced birth weight.