Amniocentesis

Hi ladies, I was wondering pros and cons on amnio. I am pregnant with twins. Past few ultrasounds Baby B has been measuring behind and at each appt for the past month the difference in measurement has increased. Now he’s about 3 weeks behind. I just met with the MFM and she said she’s concerned because of slow growth and mentioned amnio. I really am hesitant to do it. We did NIPT and AFP testing and it came back negative. I really don’t want to do it bc of the risks. I don’t know what to do besides pray. Thoughts on amnio?