A positive pregnancy test in the post-menopausal psychiatric patient-: what to think?

Assaying the serum β-hCG is the pregnancy test employed to verify an early pregnancy. It becomes positive at approximately 10 days after conception. Knowing whether or not a patient is pregnant is critical to avoid exposure to medications or procedures that might be teratogenic. Psychiatric patients are sometimes suboptimal historians, so such β-hCG testing is especially worthwhile to assure recognition of an active, early-stage pregnancy.In normal pregnancy, the serum β-hCG level doubles every 2 to 3 days for the first eight weeks or so. Minimally raised, non-escalating β-hCG concentrations are documented in non-pregnant, post-menopausal women. Repeating the assay in 12 to 36 hours would help to clarify a non-pregnant status, because there is no rapid escalation in the post-menopausal β-hCG level. In normal pregnancy, expect at least a 30-percent increase in β-hCG concentration over this time period. Ectopic pregnancies, some neoplasia, and other conditions may also elevate the β-hCG, but again, not in the escalating patterns of normal pregnancy. In those cases, further workup may be needed. The very rapid, accurate detection of an early pregnancy is an important part of safe medical practice and better patient care.