Published online by Cambridge University Press: 16 April 2025
Thyroid hormones are essential for metabolism and growth in almost all tissues. In reproduction, thyroid hormones affect steroidogenesis, ovulation, implantation, placental vascularisation and the maintenance of pregnancy and neurocognitive development of the child. The thyroid and reproductive axis are closely intertwined. Prior to describing early-pregnant thyroid physiology, non-pregnant thyroid physiology and its environmental influences, the interaction of the hypothalamic-pituitary-thyroid- and -ovarian axis and the action of thyroid hormones on the reproductive organs are described. In the foetus, the thyroid is the first endocrine gland to develop from 5 weeks of gestation, with a functional pituitary axis around week 20, but only fully mature at birth. For the rapid neuronal proliferation and growth, thyroid hormone receptors are present in the fetal brain from around 8-9 weeks of gestation. The foetus depends on the mothers thyroid hormone supply until 20 weeks of gestation.
To save this book to your Kindle, first ensure [email protected] 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 saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved 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.
Find out more about the Kindle Personal Document Service.
To save 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 saving content to Dropbox.
To save 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 saving content to Google Drive.