Schedule of Prenatal Care. Specific schedules of prenatal care vary from provider to provider, but a general schedule follows below, as well as some of the screening tests or activities you might expect at various visits.
radioisotope. a radioactive form of an element, consisting of atoms with unstable nuclei, which undergo radioactive decay to stable forms, emitting characteristic alpha, beta, or gamma radiation. These may occur naturally, as in the cases of radium and uranium, or may be created artificially.
Hydrogen has three naturally occurring isotopes: H (protium), H (deuterium), and H (tritium). Other highly unstable nuclei (H to H) have been synthesized in the laboratory, but do not occur in nature. The most stable radioisotope of hydrogen is tritium, with a half-life of 12.32 years. All heavier isotopes are synthetic and have a half-life less than a zeptosecond (10sec). Of these, H is the most stable, and the least stable isotope is H .