Medical science has documented that pregnancies grow at a certain rate. Although there are some differences in the sizes of babies throughout pregnancy, a concern can develop when the stage of pregnancy and the expected size do not correspond.
Evaluation includes performing an ultrasound to look for abnormalities of the baby and for the amount of amniotic fluid present. A finding of a fetus having fetal growth restriction may mean that the placenta is not functioning adequately. In this situation, close follow up of the pregnancy is necessary, including fetal testing and dopplers.
What would cause my baby to be larger than expected?
Several conditions make a baby seem larger than expected, including diabetes, excess amniotic fluid and more unusual conditions, such as blood incompatibility problems. There are cases in which some babies are just larger than normal.
What would cause my baby to be smaller than expected?
Occasionally, there is an inadequate amount of amniotic fluid that may be a symptom of a fetus's poor kidney function. Another cause is inadequate blood supply to the placenta, which may be related to hypertension during pregnancy.