My only "experience" is with my sister's monochorionic di-amniotic (ie. identical) twins. In her case there was a problem with the placenta (called twin-to-twin transfusion) which is a rare complication that occurs only in identical twins sharing a placenta. She had to have emergency experimental surgery to deal with the problem. One twin was much smaller than the other. Due to the complications, they had to be delivered by emergency caesarian section at 30 weeks. Both survived. Both are developing normally, although one is about 6 months "delayed" in physical development, but all IQ tests and other mental development tests have been normal.
A friend of mine delivered healthy non-identical twin boys with no complications. One was 3.6 kg at birth, the other 2.5kg. Both within normal limits for a newborn. Both thriving. One significantly smaller than the other.
Downs Syndrome 2997taylormadeinjaxfl The overwhelming majority of people who get a positive triple- or quad-screen have perfectly healthy babies. That is the...
Talk to your doctor if you have any concerns. However, if the U-S was normal and all doctors are saying their growth is within normal limits, there is probably no need to worry. As you said yourself - they are fraternal twins so there is no reason for them to be the same, like you would expect of identical twins. Also, one was always smaller, so there is no sudden drop-off in growth that would indicate a major problem. The heart beat is good, the ultrasound was good... Only a doctor will be able to tell you if there is any risk buttociated with the slower growth of one of them.
