<s>[INST] Hello Do the following if the child has microcephaly. And a few percent chance mental retardation. bpd:43mm ofd:53mm hc:150.8mm cm:4.7mm tcd:17mm ventriculum atrium:5.6mm tad:48mm apad:46mm ac:147.7mm fl:32mm humerus:32mm age of fetus:21week+5days estimated fetal weight hadlock(bpd-hc-ac-fl):313g 11oz also amniotic synthesis the QF-PCRmethod for chromosomes 21,13,18,x and y is normal [/INST] Hi, Regarding your concern, I would explain that this is a complication related to the fetal development. Genetic mutations can lead to this malformation. Other possible causes to consider are the deficiency of folic acid in the first trimester, Chat Doctor.  Unfortunately as the brain is small and not well-developed retardation and seizures occur commonly. You should consult with a pediatrician on these issues. Hope to have been helpful. Let me know if I can assist you further. Kind regards,  </s>