Baby still measuring small!!!

So I have to go get an ultrasound 2 days out the week....they monitor blood flow through the umbilical cord...the fluids surround her and the placenta...they said everything looks well....measuring small....I'm 34 weeks and she only weigh 3 pounds...but she's measuring at 29 weeks and they said her belly is measuring small as well....at my obgyn appointment she said they will be inducing me at 39 weeks...that they don't want to let me go full term with her because the placenta isn't giving her enough nutrients for her to grow well and there's a chance that she could have a birth defect if I go to 40 weeks...I don't know what could have went wrong...I don't smoke and took my prenatal vitamins the whole time...have anyone else went through this or going through this??is there anything I could do to get baby to gain more weight???I'm trying not to stress but it's making me sad because I wanted to be able to bring her home with me wasn't looking forward to her being in nicu..