الفهرس 
ANATOMY OF THE OVARYOnly 14 pages are availabe for public view
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Abstract
The purpose of this research was to study the normal pre- and postnatal development of albino rat ovary, to investigate the effect of induced hypothyroidism during the pre- and postnatal periods of life on fetal and developing rat ovaries and to evaluate the role of thyroid replacement therapy.
In this study twenty pregnant female rats and seventy female pups were used and divided into three groups;
• Control group,
• Hypothyroid group, where 0.01% PTU (propyl thiouracil) was given to the mothers in the drinking water via oral tube from 8th day of gestation and during lactation period and to the pups after weaning to the time of scarification. And
• Replacement group which received intraperitoneal injections of )10 µg/ 100 gm body weight( thyroxine every two days starting from the day of birth (day zero) to the time of scarification at 35th and 60th postnatal days. Mothers of this group received PTU as hypothyroid group.
Groups were subdivided according to the time of sacrification into:
• Prenatal (control / hypothyroid) subgroups in which the specimens were obtained at 15th and 20th intrauterine day.
• Postnatal (control / hypothyroid) subgroups in which the specimens were obtained at 1st, 15th, 35th, and 60th days after birth.
• Some rats of hypothyroid subgroup received thyroxine from birth (replacement group) and scarified at 35th and 60th day after birth.
The ovaries of these groups were removed quickly and were prepared for light and transmission electron microscopic examinations. The specimens for light microscopic examination were stained with Haematoxylin and Eosin. Other sections were stained with Masson’s Trichrome.
Ovary of hypothyroid group revealed delayed development in the prenatal period and delayed development and maturity in the postnatal period which were represented by the formation of abnormal, bi-ovular, follicles and cysts in addition to decrease in all types of normal follicles and absence of mature Graafian and other postovulatory follicles at the age of 60th postnatal day. There was also great increase in degenerated follicles on expense of normal ones with existance of hemorrhage inside and between follicles. The results of replacement group were nearly similar to that in control group where the follicular development was improved and the maturation occurred in time.
In conclusion, this study can support the hypothesis that normal thyroid function and euthyroid state is essential to normal pre and postnatal ovarian development. Hypothyroidism delayed the development and maturity of the rat ovary. It was suggested that replacement by thyroxine in early life can produce reversibility of damaged hypothyroid ovary.
Further studies are recommended to explain the occurrence of polycystic ovary syndrome with hypothyroidism and its relation with infertility and to evaluate the role of thyroid replacement therapy in such cases.