Tests for<unk> s include ultrasound examination and measurement of maternal serum alpha-fetoprotein (MSAFP). Second trimester ultrasound is recommended as the primary screening tool for<unk> s, and MSAFP as a secondary screening tool. This is due to increased safety, increased sensitivity and decreased false positive rate of ultrasound as compared to MSAFP. Amniotic fluid alpha-fetoprotein (AFAFP) and amniotic fluid acetylcholinesterase (AFAChE) tests are also used to confirming if ultrasound screening indicates a positive risk. Often, these<unk> s are apparent at birth, but acute<unk> s may not be diagnosed until much later in life. An elevated MSAFP measured at 16–18 weeks gestation is a good predictor of open<unk> s, however the test has a very high false positive rate, (2% of all women tested in Ontario, Canada between 1993 and 2000 tested positive without having an open<unk> , although 5% is the commonly quoted result worldwide) and only a portion of<unk> s are<unk> ed by this screen test (73% in the same Ontario study). MSAFP screening combined with routine ultrasonography has the best<unk> ion rate although<unk> ion by ultrasonography is dependent on operator training and the quality of the equipment.
Neural tube defect
Birth defect
Congenital limb deformities
Craniofacial abnormality
Vocal cord dysfunction
Neonatal sepsis
Perinatal asphyxia
Renal hypoplasia