A prospective study of early pregnancy loss in humans

Abstract

Objective: To test two hypotheses: In spontaneous conceptions, early pregnancy loss (EPL) is associated with [1] inadequate luteal (ovarian) P, and/or [2] elevated follicular (adrenal) P. Design: A population-based prospective study. Setting: Thirty rural Bolivian communities. Patient(s): Women volunteers (n = 191), 19–40 years old, in stable sexual unions and not using contraception. Intervention(s): Collection of serial saliva samples throughout sequential ovarian cycles and urine samples during late luteal phases. Collections continued throughout pregnancy for each detected conception. Main Outcome Measure(s): Occurrence of spontaneous conceptions and subsequent outcomes. Salivary concen trations of P. Test for elevated urinary human chorionic gonadotropin (hCG). Result(s): Luteal (through implantation) P levels were similar in pregnancies lost within 5 weeks after conception (EPL; n = 8) and those pregnancies that were maintained longer (sustained conceptions, SC; n = 32). Follicular P was significantly higher in EPL than in SC. Conclusion(s): [1] Elevated follicular P was associated with EPL in natural conceptions in healthy women. [2] Early pregnancy loss exhibits absolute luteal P levels comparable to SC, but lower luteal/follicular P ratios. (Fertil Steril 2006;86:373–9. ©2006 by American Society for Reproductive Medicine.)