Guidelines indicate that as soon as you get diagnosed with pregnancy, you need to get a thyroid profile done. This is because, eltroxin requirements may need an increase during pregnancy because of increased demand. The requirements may vary for different individuals. So you need to determine your levels as soon as you get pregnant. The further management is as follows: 1.If the test indicates you need to increase the dosage of eltroxin, your doctor will increase it. Then you need to get a thyroid profile done after 4 weeks. If you don t require further dosage adjustments, the thyroid profile can be done once every 6 to 8 weeks till the end of pregnancy. 2.If the test indicates you don t need to increase the dosage of eltroxin, your doctor won t increase it. Then you need to get a thyroid profile every 6 to 8 weeks till the end of pregnancy. After delivery your eltroxin dosage can come back to the pre-pregnancy level. One important thing to take care of is the prenatal vitamins you are given contains iron. Iron decreases the eltroxin absorption from your gut. So you should wait for 2 to 3 hours to take eltroxin after you take your pre natal vitamins. That s all about it.