See your MD. Consult your OB physician who can arrange for further analysis and tests. In particular, the underlying cause of the hydrocephalus and potential treatment may need to be explored. You may also need the consultation with a pediatric neurosurgeon who may need to be available for interventions after the delivery.
Consult you MD. If hydrocephalus is diagnosed, normally a patient will have a consultation with a perinatologist ( high risk specialist) she/he will discuss the severity of the problem and will outline a plan of following the problem. They may offer an amniocentesis to check for genetic problems. They may arrange a meeting with the neonatologist to make plans for after the birth, .
Learn as much as you. Can about the cause & treatment of your baby's hydrocephalus prior to delivery. Your OB may consult the fetal-maternal medicine team at lucille b. Packard hospital: http://www.Lpch.Org/clinicalspecialtiesservices/coe/mothersbabies/fetal-health/overview.Html. Great pediatric neurosurgeons at lbp, like dr. Michael edwards, will review the fetal ultrasounds. Also, see http://www.Hydroassoc.Org.