Production, chemical composition and prostaglandin F-2α content of uterine fluid in pregnant sheep

A uterine pouch was prepared surgically in ewes before mating to study the production and chemical composition of uterine secretions during pregnancy. Pregnancy was established in 6 sheep and in the first 55 days uterine fluid was present in small amounts (less than 5 ml), whereas between 109 days post coitum and 3 days post partum the volume ranged from 90 to 775 ml. The chemical composition of uterine fluid in pregnancy differed from that of plasma especially in respect of its high concentration of total calcium (up to 83.5 mM) and prostaglandin (PG) F-2a (up to 1500 ng/ml). Progesterone was implicated as an important endocrine factor since uterine fluid (188 ml) with a high concentration of total calcium (53-5 mM) and PGF-2a(235ng/ml) was recovered from a non-pregnant sheep treated with progesterone for 115 days.