Suppression of concentration of endometrial prostaglandin in early intra-uterine and ectopic pregnancy in women

J Endocrinol. 1980 Jun;85(3):379-86. doi: 10.1677/joe.0.0850379.

Abstract

Concentrations of prostaglandin F2 alpha (PGF2 alpha) and prostaglandin E (PGE) were measured in endometrium from 18 women with ectopic pregnancies. In the nine pregnancies not associated with vaginal bleeding or an intra-uterine contraceptive device (IUCD; intact ectopics), concentrations of PGF2 alpha (12.8 +/- 7.4 (S.E.M.) ng/g) and PGE (4.7 +/- 3.0 ng/g) were similar to those in decidua from nine intra-uterine pregnancies of comparable gestational age (14.4 +/- 4.4 and 8.2 +/- 2.2 ng/g respectively). In both ectopic and intra-uterine pregnancies concentrations of prostaglandins were significantly lower than those found in endometrium throughout the normal menstrual cycle (P < 0.01). In nine ectopic pregnancies with associated vaginal bleeding and/or an IUCD, concentrations of PGF2 alpha and PGE were significantly higher than in the intact group (P < 0.05), although the concentration of PGF2 alpha remained significantly lower than levels in normal secretory endometrium (P < 0.05). These results suggested that suppression of endometrial synsthesis of prostaglandin during early pregnancy may be mediated systemically rather than through a local action of the conceptus.

PIP: Decidua obtained by curettage from 18 women with ectopic pregnancies were studied to determine if suppression of prostaglandin production by the endometrium is a secondary effect due to continued secretion of progesterone by the corpus luteum or whether it results from a direct action of the conceptus on production and/or metabolism of prostaglandin within the endometrium. Endometrial concentrations of prostaglandin F2alpha (PGF2a) and prostaglandin E (PGE) were measured. Gestational age ranged from 31 to 100 days. Endometrial samples were also collected from 11 women undergoing therapeutic termination of a normal intra-uterine pregnancy ranging from 42 to 75 days gestation, and from 21 women with normal menstrual cycles. In 9 pregnancies not associated with vaginal bleeding or an IUD, levels of PGF2a (12.8 + or - 7.4 ng/g) and PGE (4.7 + or - 3.0 ng/g) were similar to those in decidua from 9 intrauterine pregnancies of comparable gestational ages (14.4 + or - 4.4 and 8.2 + or - 2.2 ng/g respectively.) In both ectopic and intrauterine pregnancies, PG levels were significantly lower than those observed in endometrium throughout the normal menstrual cycle (P 0.01). 9 ectopic pregnancies with associated vaginal bleeding and/or an IUD had PG levels significantly higher than those in the intact group (P 0.05), although PG levels were significantly lower than levels in normal secretory endometrium (P 0.05). Suppression of endometrial synthesis of PGs during early pregnancy may be mediated systemically rather than through a local action of the conceptus.

MeSH terms

  • Chorionic Gonadotropin / blood
  • Endometrium / metabolism*
  • Estradiol / blood
  • Female
  • Humans
  • Menstruation
  • Pregnancy*
  • Pregnancy, Ectopic / metabolism*
  • Progesterone / blood
  • Prostaglandins E / metabolism*
  • Prostaglandins F / metabolism*

Substances

  • Chorionic Gonadotropin
  • Prostaglandins E
  • Prostaglandins F
  • Progesterone
  • Estradiol