Cervical ripening after treatment with prostaglandin E2 or antiprogestin (RU486). Possible mechanisms in relation to gonadal steroids.
OBJECTIVE
To compare the mechanisms for cervical ripening after treatment with prostaglandin E2 or antiprogestin (RU486) to spontaneous cervical ripening, with focus on gonadal steroid receptors.


METHODS
Cervical biopsies were obtained from postpartal women after treatment with prostaglandin E2 (n=10), or antiprogestin (n=5). Postpartal women after spontaneous cervical ripening (n=10) served as controls. Levels of estrogen and progesterone receptors, their mRNAs, insulin-like growth factor I mRNA and serum estradiol and progesterone were quantitated. The collagen concentration and solubility by pepsin were determined. Statistical tests used were Kruskal-Wallis and Mann-Whitney U test.


RESULTS
After prostaglandin E2 treatment the collagen concentration was higher (P<0.05) as compared to spontaneous ripening. After antiprogestin treatment the estrogen receptor concentration was higher (P<0.05) in comparison to spontaneous ripening.


CONCLUSIONS
The elevated estrogen receptor concentration after antiprogestin treatment, in contrast to spontaneous ripening, and prostaglandin E2 treatment, indicates a that a receptor-mediated progesterone withdrawal does not explain the events behind spontaneous cervical ripening at parturition.
Stjernholm
Y M
YM
Department of Woman and Child Health, Karolinska Hospital, Stockholm, Sweden.
Sahlin
L
L
Eriksson
H A
HA
Byström
B E
BE
Stenlund
P M
PM
Ekman
G E
GE
D000328:Adult; D001706:Biopsy; D020070:Cervical Ripening / Q000187:drug effects*; D002584:Cervix Uteri / Q000502:physiology* / Q000601:surgery; D003094:Collagen / Q000032:analysis; D015232:Dinoprostone / Q000627:therapeutic use*; D004958:Estradiol / Q000097:blood; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007124:Immunoenzyme Techniques; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D015735:Mifepristone / Q000627:therapeutic use*; D010865:Pilot Projects; D011374:Progesterone / Q000097:blood; D015347:RNA Probes / Q000737:chemistry; D012333:RNA, Messenger / Q000737:chemistry; D011960:Receptors, Estrogen / Q000032:analysis / Q000502:physiology*; D011980:Receptors, Progesterone / Q000032:analysis / Q000502:physiology*
D015347:RNA Probes; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D015735:Mifepristone; D011374:Progesterone; D004958:Estradiol; D007334:Insulin-Like Growth Factor I; D003094:Collagen; D015232:Dinoprostone