Articles on Medical Diseases and Conditions

Entries for the ‘Tests in Obstetrics’ Category

Biochemical Tests for Congenital Anomalies

Besides giving information on fetal well-being, amniocentesis makes it possible to test for various congenital anomalies via biochemical analysis of amniotic fluid and tissue culture chromosome studies of fetal cells (see Chapter 34). In addition, certain substances of fetal origin may appear in maternal serum. In some cases it is possible to detect certain fetal […]

Fetal Maturity Tests

Tests for monitoring fetal maturity via amniocentesis are also available. Bilirubin levels in erythroblastosis are discussed in chapter 11. Amniotic creatinine assay, amniotic epithelial cell stain with Nile blue sulfate, fat droplet evaluation, osmolality, and the Clemens shake test, alone or in combination, have been tried with varying and not entirely satisfactory results. Most current […]

Fetal or Placental Function

Urine estriol or total estrogens. Estriol is an estrogenic compound produced by the placenta from precursors derived from fetal adrenal cortex and fetal liver. Newly synthesized estriol is unconjugated; therefore, unconjugated estriol represents a product of the entire fetoplacental unit. The unconjugated estriol reaches maternal serum (where it has a half-life of about 20 minutes) […]

Pregnancy Tests

Most pregnancy tests are based on the fact that the placenta secretes human chorionic gonadotropin (hCG), a hormone that has a luteinizing action on ovarian follicles and probably has other functions that are not completely known. Serum hCG levels of about 25 milli-international units (mIU)/ ml (IU/L) are reached about 8-10 days after conception. The […]