Book chapters will be unavailable on Saturday 24th August between 8am-12pm BST. This is for essential maintenance which will provide improved performance going forwards. Please accept our apologies for any inconvenience caused.
To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
This chapter reviews the major physiological adaptations during pregnancy and also highlights changes in the reference ranges of common laboratory values encountered in pregnancy. Pregnancy induces a myriad of changes involving the cardiovascular system, respiratory system, gastrointestinal and hepatobiliary systems and genitourinary system. Pregnancy is associated with an overall increase in the serum concentrations of total cortisol, free cortisol, aldosterone, deoxycorticosterone, corticosteroid binding globulin, and adrenocorticotropic hormone. Pituitary enlargement occurs in pregnancy by estrogen mediated proliferation of prolactin-producing cells. During the first trimester of pregnancy, total thyroxine and total tri iodothyronine concentrations begin to increase and peak at mid-gestation, primarily as a result of increased production of thyroid-binding globulin. The immunological adaptations of pregnancy, particularly at the maternal-fetal interface, comprise complex mechanisms that enable the fetus to grow while preventing the mother from rejecting the fetus.