Question: Hi. I've just got back my 13 weeks ultrasound scan and reports (fraternal twins). The ultrasounds were just 5 quick images, were not detailed ultrasounds as at 11.3 weeks. But the results came back saying the following (please see results below). I am very worried about the BPD of 19 and 16.7 (very, as I've been told by some people it may be a marker of spina bifida). Some of the other results are also developing somewhat slower than should be the case at 13 weeks maybe (?) One fo the twins has had a gestational sac in a banana shape since the beginning - it has now expanded somewhat but is still like a kidney bean now. We had NIPT blood test done at 11.5 weeks and that came back all clear (we are having girls). Can you please tell me if I should be worried with the BPD especially and if there are any specific questions I should be asking my doctor when I next see him.
(1) BPD 19, OFP 25, HC 70, AC 54, FL 8, CRL 65
(2) BPD 16.7, OFP 25, HC 70, AC 62, FL 9, CRL 65
Weight 60g and 64g
Heart beat 148 and 154
All other checked and normal
Nose bones 2mm and 2.3mm

Is the kidney bean shaped gestational sac okay?