if your baby’s growth has been fine for the gestational age then it would suggest that baby has been doing pretty well. if a hand/hands of your baby are open on an ultrasound it is a great indication that it is not trisomy18. babies with trisomy18 cannot open their hands normally. if worried you may consider getting another ultrasound scan done to thoroughly look for other features or markers suggestive of chromosomal abnormalities. getting amniocentesis done would also help to confirm or rule out genetic problems in baby. discuss with your treating doctor/gynecologist or genetic specialist for further clarification and assistance. take care.
im currently 18. 4 weeks pregnant. afp results came back 1:41 chance of trisomy 18. at the 12 week ultrasound baby had grown on time from the 9 week ultrasound and had a wide open hand and at the 16 week ultrasound baby was in time head normal size compared to body and hands wide open with that does it seem to have it? also my mom had spina bifida so is it possible i carry the gene and it will always be positive?