Types and patterns of anencephaly

A report may describe how much cranial tissue is affected or whether the defect extends into the spine. The wording can vary between specialists, so the anatomical description is often more useful than a subtype label.

Anencephaly belongs to the group called neural tube defects. Clinicians may describe a more limited cranial defect, extensive absence involving the skull and brain, or craniorachischisis when an open defect continues from the head into the spine. These descriptions identify anatomy; they do not represent mild versions with normal brain development.

Other neural tube defects, including encephalocele and spina bifida, are separate diagnoses. Their appearance, counselling, and possible outcomes differ, which is why specialist review of the ultrasound matters when the first scan is uncertain.

Request a written explanation of the structures seen on ultrasound and whether the spine is also involved. A detailed scan by a fetal-medicine specialist can distinguish anencephaly from another cranial or spinal condition and can check the rest of the baby's anatomy.

Once the diagnosis is clear, the team should explain expected outcomes and pregnancy options in language you understand. You may wish to include a partner, relative, counsellor, or faith adviser in those discussions.

Contact urgent maternity care for heavy bleeding, leaking fluid, severe or persistent abdominal pain, fainting, breathing difficulty, a seizure, or a severe headache accompanied by visual disturbance. A change in the baby's usual movements later in pregnancy also needs prompt assessment. These symptoms are triaged for the pregnant person's safety, not according to the subtype written on an ultrasound report.

Ask whether the label describes anencephaly alone or a defect involving the spine, and whether any finding remains uncertain. Also ask what follow-up is planned, who can provide emotional support, and what preconception measures should be considered if you later plan another pregnancy.