I want to know if I should be worried. My doctor says I'm 29weeks but I'm measuring 34weeks I'm scared and I don't want to have a big baby

Fundal height measurements are the least accurate way of determining size of baby so try not to worry. Your measurement can be effected by a number of reasons besides baby's possible size: length of your torso, number of pregnancies, amount of amniotic fluid at the time they measure, baby's position, location of placenta, baby's growth pattern. Sometimes it will be determined that the pregnancy is actually a bit further along than first thought.

Some women will naturally measure a bit ahead, some behind without it being an issue. Cause for further investigation comes when there is a progressively large range between number of weeks gestation and fundal height measurement. If measurement is very behind, or much farther ahead repeatedly, they will look into it with ultrasound to better determine baby's size and development.

What did your doctor say about it? Will they just wait and see how things are next visit... are they going to do an ultrasound or wait and see?