What should you know about anencephaly brain?

It begins very early in pregnancy when the upper end of the neural tube does not close as expected. The missing skull covering leaves developing brain tissue exposed and prevents normal brain development. Sadly, the condition cannot be repaired and is not compatible with long-term survival after birth.

The neural tube is the early structure that later forms the brain and spinal cord. In anencephaly, its upper portion remains open, so the forebrain, much of the cerebrum, the skull vault and the skin that should cover them are absent or severely underdeveloped. Some lower brain structures may be present, but they cannot support normal awareness, movement or other brain functions.

Anencephaly differs from conditions in which the skull is absent but more brain tissue is initially present. A fetal medicine specialist interprets the full pattern rather than relying on one image or one term in a report.

Ask for a detailed ultrasound with a maternal-fetal medicine specialist to confirm the findings and check the rest of the fetus. Your team can explain available pregnancy options, what to expect with each option, and which services are available locally. You may also be offered genetic counselling or testing when the scan shows other differences.

Bring a support person if you wish, request written information, and take time to repeat questions. Perinatal palliative care, bereavement support and mental-health care can help whether the pregnancy continues or ends.

Contact your maternity team promptly if a scan report mentions absent skull bones, abnormal brain development or a suspected neural tube defect so that specialist assessment can be arranged. Seek urgent maternity care for heavy bleeding, severe abdominal pain, leaking fluid, fainting, fever, or a marked change in fetal movement after movements have become established. These symptoms need assessment regardless of the fetal diagnosis.

You might ask which brain and skull structures were seen, whether another specialist should review the images, and whether any additional differences were found. Other useful questions cover the expected course of the pregnancy, choices available to you, comfort care after birth, testing that may clarify recurrence considerations, and emotional support for you and your family.