biochemical pregnancy
A very early pregnancy loss detected only by blood hormone levels without clinical or ultrasound evidence of pregnancy.
Full Definition
A biochemical pregnancy, also called a chemical pregnancy, is a very early pregnancy loss that occurs shortly after implantation, typically before the fifth week of gestation. This condition is characterized by positive pregnancy tests (elevated beta-hCG levels) followed by declining hormone levels without any clinical evidence of pregnancy such as gestational sac visualization on ultrasound. Biochemical pregnancies are relatively common in both natural conception and assisted reproductive technology cycles, accounting for a significant proportion of early pregnancy losses. While emotionally difficult for patients, biochemical pregnancies are generally considered a positive prognostic sign as they indicate that fertilization, implantation, and initial hormone production occurred. These events are often related to chromosomal abnormalities in the embryo and typically resolve without medical intervention.
Usage
Usage note: Synonym with chemical pregnancy; distinguish from clinical pregnancy in documentation.
In Context
- "The patient experienced a biochemical pregnancy with beta-hCG levels peaking at 45 mIU/mL." — Pregnancy monitoring record
- "Biochemical pregnancy was diagnosed when hormone levels declined before ultrasound confirmation." — Clinical documentation