الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Major hormonal changes emerge during pregnancy and it is
important to know what ’normal’ parameters of physiological changes
during pregnancy in order to diagnose and manage common medical
problems of pregnancy, such as hypertension, gestational diabetes,
anaemia and hyperthyroidism.
The pituitary gland is one of the most affected organs with altered
anatomy and physiology. Due to physiological changes in the pituitary
and target hormone levels, binding globulins, and placental hormones,
hormonal evaluation becomes more complex in pregnant women. As a
consequence of physiological hormonal changes, the evaluation of
pituitary functions in pregnant women is quite different from that done in
the prepregnant state. Pituitary adenomas may cause problems by their
hormone secretion that affects the mother and the fetus besides causing
an increased risk of tumor growth. Furthermore, diagnosis, course, and
treatment of pituitary diseases point out differences.
Pregnancy has profound effects on the regulation of thyroid
function in healthy women and patients with thyroid disorders. These
effects need to be recognized, precisely assessed, clearly interpreted, and
correctly managed. For healthy pregnant women who reside in areas with
a restricted iodine intake, relative hypothyroxinemia & goitrogenesis
occur frequently, indicating that pregnancy constitutes a challenge for the
thyroidal economy Overt thyroid dysfunction occurs in 2-3% of
pregnancies, but subclinical thyroid dysfunction (both hyper- &
hypothyroidism) is probably more prevalent and frequently remains
undiagnosed, unless specific screening programs are initiated to disclose
thyroid function abnormalities in early gestation. Maternal alterations of
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thyroid function due to iodine deficiency, hypothyroidism and
hyperthyroidism have important implications on fetal/neonatal outcome.
In recent years, particular attention has been focused on potential
developmental risks for the fetuses of women with hypothyroxinemia
during early gestation Pregnancy increases the metabolic rate, blood flow,
heart rate, and cardiac output, and various subjective sensations such as
fatigue and heat intolerance that may suggest the possibility of coexistent
thyrotoxicosis. It must be kept in mind when treating thyrotoxic patients,
since all ATD cross the placenta and may affect fetal thyroid function.
Fetal and neonatal hyperthyroidism is due to the transplacental transfer of
maternal stimulating TSH-receptor antibodies (TRAb). It may occur in
infants born to women with active Graves’ disease, but also to women
who have had prior definitive cure of their disease by surgery or
radioactive iodine, but maintain high titers of TRAb. The proper
management of pregnant patients with Graves’ disease remains a difficult
challenge in clinical endocrinology. Thyroid nodules discovered during
pregnancy should be aspirated for cytological diagnosis. If a malignancy
is diagnosed, surgery should be performed during pregnancy or shortly
thereafter. Pregnancy by itself does not adversely affect the natural
history of differentiated thyroid carcinoma. During the postpartum period,
particular attention should be given to women with thyroid autoimmunity,
since hypothyroidism and hyperthyroidism are frequently exacerbated in
the months following the delivery.
During pregnancy and lactation, novel regulatory systems specific
to these settings complement the usual regulators of calcium homeostasis.
Intestinal calcium absorption doubles from early in pregnancy in order to
meet the fetal demand for calcium. In comparison, skeletal calcium
resorption is a dominant mechanism by which calcium is supplied to the
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breast milk, while renal calcium conservation is also apparent. While
calcium supplementation during pregnancy will enable the mother to
absorb more calcium, it is clear from clinical trials and observational
studies that calcium supplements have little or no impact on the amount
of bone lost during lactation. The skeleton recovers promptly from
lactation to achieve the pre-pregnancy bone mass through mechanisms
that remain unclear. The transient loss of bone mass during lactation can
compromise skeletal strength and lead to fragility fractures in some
women. But the vast majority of women can be assured that the changes
in calcium and bone metabolism during pregnancy and lactation are
normal, healthy, and without adverse consequences in the long-term.
The outlook for pregnancy in women with pre-existing diabetes has
potential to improve as rapid advances in diabetes management, fetal
surveillance, and neonatal care emerge. However, the greatest challenge
to face is the growing number of women developing GDM and Type 2
DM as the obesity epidemic increases and obesity-related complications
exert a further deleterious effect. The development of Type 2 DM in the
mother of GDM women as well as obesity and glucose intolerance in the
offspring of women with preexisting DM or GDM set the stage for a
perpetuating cycle that must be aggressively addressed with effective
primary prevention strategies that begin in-utero Pregnancy is clearly a
unique opportunity to implement strategies to improve the mother’s
lifetime risk for cardiovascular disease in addition to that of her offspring.
The relative hypercortisolism and hyperaldosteronism of normal
pregnancy are not generally clinically apparent. Adrenal disorders
occurring in pregnancy cause significant maternal and fetal morbidity.