THE ROLE OF A SINGLE PROGESTERONE MEASUREMENT IN THE DIAGNOSIS OF EARLY-PREGNANCY FAILURE AND THE PROGNOSIS OF FETAL VIABILITY

Objective To assess the role of a single maternal serum progesterone m easurement in the immediate diagnosis of early pregnancy failure and i n the long term prognosis of fetal viability. Design A prospective com parative study of women presenting with vaginal bleeding and abdominal pain in early pregnancy. The comparison group was defined retrospecti vely as women who presented with abdominal pain without history of, or the subsequent occurrence of, vaginal bleeding and whose pregnancies continued to viability. The study groups were defined retrospectively as threatened-continuing, non-continuing (including blighted ovum, mis sed abortion, incomplete and complete abortion) and tubal pregnancy gr oups, according to the outcome of the pregnancies. Setting The emergen cy room at the gynaecology department of a teaching hospital. Subjects Four hundred and eighty-nine women presenting with singleton pregnanc y, vaginal bleeding and/or abdominal pain in the first 18 weeks of pre gnancy. The comparison group comprised 131 women without vaginal bleed ing whose pregnancies continued to viability. The study group comprise d 358 women with 148 threatened-continuing pregnancies, 175 non-contin uing and 35 tubal pregnancies. Interventions A 10 ml blood sample was taken and pelvic ultrasonography was performed at presentation. Otherw ise, conventional management was used. Main outcome measures Progester one levels were interpreted in accordance with the outcome of the preg nancy: comparison, threatened-continuing, non-continuing or tubal. Via bility was defined as 28 weeks or more weeks of gestation. Results Pro gesterone levels were significantly lower in the non-continuing and tu bal pregnancy groups than in the comparison and threatened-continuing groups (P < 0.001 in all cases). A cut-off level at 45 nmol/l was foun d to differentiate between the viable (comparison and threatened-conti nuing) pregnancies and the abnormal (non-continuing and tubal) pregnan cies with 87.6% sensitivity and 87.5% specificity. Conclusions A singl e serum progesterone measurement taken in early pregnancy is valuable in the immediate diagnosis of early pregnancy failure and the long ter m prognosis of viability.