Fetal and Maternal Plasma Thyroid Hormone’s Levelsin the Guinea Pigs

Abstract

Background: All available data indicate that the thyroid of the guinea pig fetus is capable of functioning
independently of that of the mother . Therefor fetal thyroid function is necessary for normal growth in utero.
Intrauterine adaptation to the outside environment is important mechanism via which fetus increases the
chance to thrive after birth. Aim and Objective of this work to assess the plasma level of thyroxin (T4) and
Triiodothyronine (T3) through most period of pregnancy in fetal and maternal guinea pigs. Materials and
Methods: Blood samples collected from 51pregnant guinea pigsand their fetuses(93), by the Cobase 411
device produced by, Roche com. and it works with technology Electro, Plasma T4 and T3 were measured by
ChemiLuminescence immune-assay. Results: Fetal plasma Thyroxin (T4) concentration was greater than
that of the mother between Results 50 and 62 days of gestation while fetal plasma T3 concentration was less
than that of the mother throughout gestation. In fetalguinea pig the reciprocal relationship between pituitary
and thyroid is established at approximately day 34-35 of gestation. Conclusion: Theresults indicated that
the fetal pituitary–thyroid system (PTS) is functioning at a relatively high level than that of the maternal,
starting few days beforethe second half of pregnancy .Thyroid hormones are important for fetal growth and
maturation event.