Ob- : A prefix signifying to, toward, before, against, reversely, etc.; also, as a simple intensive; as in oblige, to bind to; obstacle, something standing before; object, lit., to throw against; obovate, reversely, ovate. Ob- is commonly assimilated before c, f, g, and p, to oc-, of-, og-, and op-.

Example:
When does the OB start seeing you every 2 weeks?

Taxonomy
pregnancy, fetus, risk, placenta, Obstetrics, obstetrician, mother, Induction, women, first trimester, patients, risk factors, uterus, birth, ultrasound, amniocentesis, second trimester, gestational age.

Defination from the web:
obstetrician or midwife sees a pregnant woman on a regular basis to check the progress of the pregnancy, to verify the ... Maternal health · Obstetrics · Prenatal care · Pregnant patients' rights · Unintended pregnancy · Pregnancy options counseling ...