Circulating levels of inhibin A, activin A and follistatin in missed and recurrent miscarriages.
BACKGROUND
The aim of this study was to investigate the changes in circulating levels and the clinical use of inhibin A, activin A and follistatin as endocrine markers of early pregnancy loss.


METHODS
Blood samples were collected from women presenting with a sporadic missed miscarriage (n = 10), and controls having pregnancy termination at 8-12 weeks (n = 15) and from women with a history of unexplained recurrent miscarriages (n = 12) at 6-12 weeks gestation. All samples were assayed for inhibin A, inhibin B, activin A, follistatin, hCG, estradiol and progesterone.


RESULTS
Serum inhibin A, hCG, estradiol and progesterone levels were significantly ( approximately 2-3 fold) decreased in sporadic miscarriages compared with controls. In the recurrent miscarriage group, time dependent changes in plasma inhibin A and hCG levels were significantly (P < 0.05) altered in the group that had a subsequent miscarriage compared with those who had a live birth. At 6-7 weeks gestation, plasma inhibin A ( approximately 4 fold, P < 0.01), hCG ( approximately 4 fold, P < 0.01) and estradiol ( approximately 2 fold, P < 0.001) levels were significantly lower in women who went on to have another miscarriage than those with a live birth. Inhibin B levels were near the detection limit of the assay.


CONCLUSIONS
Our findings suggest that inhibin A is a specific marker of early pregnancy loss before the onset of the clinical symptoms of recurrent miscarriage. There is a high degree of association between levels of inhibin A and hCG in cases of miscarriage, indicating that these two proteins could be used in combination to predict future pregnancy outcome.
Muttukrishna
S
S
Department of Obstetrics and Gynaecology, Royal Free-UCL Medical School, 86-96 Chenies Mews, London WC1E 6HX, UK. s.muttukrishna@ucl.ac.uk
Jauniaux
E
E
Greenwold
N
N
McGarrigle
H
H
Jivraj
S
S
Carter
S
S
Elgaddal
S
S
Groome
N
N
Regan
L
L
D000026:Abortion, Habitual / Q000097:blood*; D000030:Abortion, Missed / Q000097:blood*; D028341:Activins / Q000097:blood*; D000328:Adult; D015415:Biomarkers / Q000097:blood; D006063:Chorionic Gonadotropin / Q000097:blood; D004958:Estradiol / Q000097:blood; D005260:Female; D038681:Follistatin / Q000097:blood*; D005865:Gestational Age; D006801:Humans; D028322:Inhibin-beta Subunits / Q000097:blood*; D007265:Inhibins / Q000097:blood*; D008137:Longitudinal Studies; D011247:Pregnancy; D011374:Progesterone / Q000097:blood
D015415:Biomarkers; D006063:Chorionic Gonadotropin; D038681:Follistatin; C422405:activin A; C422362:inhibin A; D028341:Activins; D011374:Progesterone; D004958:Estradiol; D007265:Inhibins; D028322:Inhibin-beta Subunits