Evaluation of serum inhibin A as a surveillance marker after conservative management of tubal pregnancy.
Tubal pregnancy is now commonly managed by laparoscopic salpingostomy or systemic methotrexate. A disadvantage of such conservative management is the need for appropriate follow-up, with serial measurement of serum concentrations of human chorionic gonadotrophin (HCG), to exclude persistent ectopic pregnancy (PEP). Concentrations of inhibin A, also a placental product, are significantly increased during pregnancy and the half-life of inhibin A is significantly shorter than that of HCG. To assess the suitability of inhibin A as a marker of PEP, we studied 16 women who had undergone surgery for a tubal pregnancy, measuring HCG and inhibin during follow-up. The mean +/- SEM time taken to achieve non-pregnant concentrations of inhibin A was significantly shorter than for HCG (4.2 +/- 0.8 days versus 21.6 +/- 4.4 days respectively; P < 0.001 Wilcoxon signed rank test). However, in all women the inhibin A concentration increased rapidly after reaching a nadir, reflecting the return of ovarian function, complicating the interpretation of results. In four women inhibin A was almost undetectable preoperatively, while the corresponding HCG concentration was high. These data suggest that inhibin A will not be a useful marker for PEP but that it may provide a more accurate preoperative assessment of trophoblast viability than HCG, thereby improving management.
Department of Obstetrics and Gynaecology, Monash University, Monash Medical Centre, Clayton, Victoria, Australia.
D
D
D'Antona
P M
PM
Mamers
P J
PJ
Lowe
N
N
Balazs
N P
NP
Groome
E M
EM
Wallace
D000328:Adult; D015415:Biomarkers / Q000097:blood; D006063:Chorionic Gonadotropin / Q000097:blood; D005260:Female; D013509:Gynecologic Surgical Procedures; D006801:Humans; D007265:Inhibins / Q000097:blood*; D010535:Laparoscopy; D011247:Pregnancy; D011274:Pregnancy, Tubal / Q000097:blood* / Q000601:surgery*; D012489:Salpingostomy; D013997:Time Factors
D015415:Biomarkers; D006063:Chorionic Gonadotropin; D007265:Inhibins