oestrogen
/glossary/glossary/oestrogen/
a type of sex steroid hormone found in men and women responsible for secondary sexual characteristics. There are three oestrogens – oestrone, oestradiol and oestriol – the most potent of which is oestradiol.

Oestrone
/hormones/oestrone/
Oestrone is a hormone produced by the ovaries, adrenal glands and fat. It is one of the major oestrogens in postmenopausal women.

Androstenedione
/hormones/androstenedione/
Androstenedione is a steroid hormone that has weak, androgenic actions on the body itself. However, it mainly acts as a stepping stone in the manufacture of testosterone and oestrogen within the body.

What is HRT?
/explore/discover/what-is-hrt/
Hormone replacement therapy (or HRT) (also known as menopausal hormone therapy; MHT) is the replacement of female sex hormones oestrogen and progesterone in women to control symptoms of the menopause.

Ovaries
/glands/ovaries/
The ovaries produce and release eggs (oocytes) into the female reproductive tract at the mid-point of each menstrual cycle. They also produce the female hormones oestrogen and progesterone and androgens.

Is my soya latte messing with my hormones?
/explore/resources/podcasts/is-my-soya-latte-messing-with-my-hormones/
Should I be concerned about growth hormones in a cow's milk cappuccino? Are the plant oestrogens in a soya latte affecting my risk of cancer? Will almond milk damage my thyroid? 

corpus luteum
/glossary/glossary/corpus-luteum/
a temporary endocrine gland formed from the ruptured ovarian follicle (which enclosed the egg) after an egg is released at ovulation. The corpus luteum produces the hormones progesterone and oestradiol (an oestrogen).

Oestradiol
/hormones/oestradiol/
Oestradiol is an important reproductive hormone that has a wide range of actions in both men and women.

Menstrual cycle: KS4 article
/explore/discover/menstrual-cycle-ks4-article/
The menstrual cycle is a repeated pattern of changes in the female body. Its purpose is to prepare the body for the possibility of pregnancy . The menstrual cycle takes about a month to complete and is driven by a variety of hormones. The hormones are used to signal when the different stages of the cycle should happen.

Sheehan's syndrome
/endocrine-conditions/sheehans-syndrome/
Sheehan's syndrome is a rare condition affecting the pituitary gland that occurs as a result of heavy bleeding during or after childbirth.

Treatment for menopause
/endocrine-conditions/treatment-for-menopause/
Lifestyle factors such as exercise, dietary factors, smoking cessation and reducing alcohol intake can improve menopause-related symptoms as well as improve heart and bone health.

Menopause
/endocrine-conditions/menopause/
The menopause is the time when menstruation stops because the ovaries stop producing hormones and releasing eggs each month. This usually marks the end of a woman's reproductive years.

Hormones of pregnancy and labour
/explore/discover/hormones-of-pregnancy-and-labour/
This article describes hormones that play an important role in pregnancy and labour.

Delayed puberty
/endocrine-conditions/delayed-puberty/
Delayed puberty is defined as no secondary sexual maturation or any sign of puberty by the age of 13 years in girls and 14 years in boys.

Dehydroepiandrosterone
/hormones/dehydroepiandrosterone/
Dehydroepiandrosterone is an important precursor hormone, and is the most abundant circulating steroid present in the human body. It has little biological effect on its own but has powerful effects when converted into other hormones such as sex steroids.

Oestriol
/hormones/oestriol/
Oestriol is a hormone made during pregnancy that can be used to measure foetal health and predict when birth may happen.

Endometrial cancer
/endocrine-conditions/endometrial-cancer/
Endometrial cancer is a form of cancer that originates from the tissue that lines the womb. This tissue is called the endometrium.

Menopause Collection
/explore/discover/menopause-collection/
Menopause affects half of the global population. Here you can explore our collection of resources about perimenopause and the menopause.

Osteoporosis
/endocrine-conditions/osteoporosis/
Osteoporosis is a bone disorder caused by loss of bone mass, resulting in abnormal bone structure and an increased risk of fracture.

Hormones in pregnancy and labour
/explore/discover/hormones-in-pregnancy-and-labour/
Hormones play an important role in pregnancy and labour. They help make sure everything happens at the right time and in the right order.

Menopause vs. manopause – are they equivalent?
/explore/resources/podcasts/menopause-vs-manopause-are-they-equivalent/
The menopause marks one of the biggest natural shifts in hormones for women and can bring with it a number of unpleasant symptoms. But is there a testosterone-based equivalent in men?

Prolactin
/hormones/prolactin/
Prolactin is a hormone produced in the pituitary gland, named because of its role in lactation. It also has other wide-ranging functions in the body, from acting on the reproductive system to influencing behaviour and regulating the immune system.

Hormones in human reproduction
/explore/discover/hormones-in-human-reproduction/
Hormones are key players in human reproduction. They ensure everything happens at the right time, from puberty to menstruation and child birth. 

Premature ovarian insufficiency
/endocrine-conditions/premature-ovarian-insufficiency/
Menopause usually happens in women over the age of 45 years, but if the ovaries stop working prematurely (i.e. before the age of 40 years), this is called ‘Premature Ovarian Insufficiency’ (POI).

Hormones in puberty
/explore/discover/hormones-in-puberty/
Puberty is when a child experiences physical and emotional changes that occur as their body begins to develop and change, transitioning into adulthood. These changes happen gradually over time.

Follicle stimulating hormone
/hormones/follicle-stimulating-hormone/
Follicle stimulating hormone is produced by the pituitary gland. It regulates the functions of both the ovaries and testes. Lack or low levels of it can cause subfertility in both men and women.

Amenorrhoea
/endocrine-conditions/amenorrhoea/
Amenorrhoea is the term used to describe a lack of 'periods' (menstrual cycles) in women. The management of amenorrhoea depends on the underlying cause.

Gonadotrophin-releasing hormone
/hormones/gonadotrophin-releasing-hormone/
Gonadotrophin-releasing hormone is released from the hypothalamus in the brain. It controls the production of luteinising hormone and follicle stimulating hormone from the pituitary gland.

Turner syndrome
/endocrine-conditions/turner-syndrome/
Turner syndrome is a chromosomal disorder affecting the equivalent of one in 2,500 girls, which may lead to a number of features including short stature, failure to enter puberty and infertility.

Placenta
/glands/placenta/
The placenta is a temporary endocrine organ formed during pregnancy, which produces hormones important in the maintenance of a healthy pregnancy and in preparation for labour and breastfeeding.

Hormones and conservation
/explore/discover/hormones-and-conservation/
The study of animal reproductive systems and regular monitoring of reproductive and stress hormones is important for conservation.

Luteinising hormone
/hormones/luteinising-hormone/
Luteinising hormone is produced by the pituitary gland and is one of the main hormones that control the reproductive system.

Angiotensin
/hormones/angiotensin/
Angiotensin is a protein hormone that causes blood vessels to become narrower. It helps to maintain blood pressure and fluid balance in the body.

Menstrual cycle
/explore/discover/menstrual-cycle/
The menstrual cycle is an important process that prepares the body for the possibility of pregnancy. Each stage is driven by reproductive hormones that are regulated by the pituitary gland.

Growth and height
/explore/discover/growth-and-height/
Ever wondered why some people are very tall and others are shorter? Or why some people grow fast and others much slower? Behind everyone’s height is a mix of genetics, hormones, nutrition, the environment and sometimes, medical conditions.

Gender identity disorder
/endocrine-conditions/gender-identity-disorder/
Gender identity disorder is where a person is dissatisfied with their biological sex, because they feel that it is different from the gender they feel they should be. This often leads to a desire to change their appearance with hormones or surgery and live in their preferred gender.

Precocious puberty
/endocrine-conditions/precocious-puberty/
Precocious puberty is the abnormally early development of any secondary sexual characteristics: before the age of nine years in a boy and eight years of age in a girl.

Premenstrual syndrome
/endocrine-conditions/premenstrual-syndrome/
Premenstrual syndrome (PMS) is a condition that affects women during the days leading up to her monthly period; it can cause distressing physical and emotional symptoms.

Endometriosis
/endocrine-conditions/endometriosis/
Endometriosis is a condition in women where the lining of the womb grows outside of the womb causing scar tissue and painful monthly periods.

Progesterone
/hormones/progesterone/
Progesterone is a hormone released by the corpus luteum in the ovary. It plays important roles in the menstrual cycle and in maintaining the early stages of pregnancy.

Hirsutism
/endocrine-conditions/hirsutism/
Hirsutism is the presence of excess male-pattern hair growth in women and is commonly caused by an imbalance of hormones.

Nelson's syndrome
/endocrine-conditions/nelsons-syndrome/
Nelson's syndrome is the name given to the enlargement of a pituitary gland tumour associated with excess secretion of adrenocorticotropic hormone following the surgical removal of both adrenal glands, usually to treat Cushing's disease.

Animal research in science
/explore/discover/animal-research-in-science/
The controlled and regulated use of laboratory animals in medical research has helped to extend our understanding of the healthy and diseased lifecourse, as well as the development of novel and effective therapeutic interventions.

Female contraceptives
/explore/resources/female-contraceptives/
Contraceptives are medications and devices that are designed to prevent unintended pregnancies.

In Vitro Fertilisation (IVF): KS4 article
/explore/discover/in-vitro-fertilisation-ivf-ks4-article/
IVF is used by couples experiencing infertility. It can overcome a number of different barriers to pregnancy. It can also be used with donor sperm and eggs, or when using a surrogate.

Mass Spectrometry Core Manager
/students/careers/mass-spectrometry-core-manager/
Natalie Homer, Mass Spectrometry Core Manager: The mass spectrometry core facility I manage has six instruments and a team of four technical specialists.

Are my hormones making me horny?
/explore/resources/podcasts/are-my-hormones-making-me-horny/
What’s the difference between sexual desire and arousal? How does the contraceptive pill affect your sex drive? Which hormone has recently been found to boost sexual arousal in both men and women?

Are everyday chemicals harming my health?
/explore/resources/podcasts/are-everyday-chemicals-harming-my-health/
There are chemicals all around us, but can they interfere with our hormones? Endocrine disruptors have been linked with a number of health problems, so for the final episode in the series we look at where these chemicals are found and whether we should be worried.

Gigantism
/endocrine-conditions/gigantism/
Gigantism is a rare condition due to abnormal, accelerated growth caused by excessive amounts of growth hormone secretion during childhood or adolescence. It is almost always the result of a growth hormone-secreting pituitary tumour.

Hypopituitarism
/endocrine-conditions/hypopituitarism/
Hypopituitarism is the failure of production of one or more hormones from the pituitary gland.

Prolactinoma
/endocrine-conditions/prolactinoma/
A prolactinoma is a benign tumour of the pituitary gland that produces excess amounts of the hormone prolactin. It responds well to medication and surgery is avoidable in the majority of cases.

Eating disorders - KS4 article
/endocrine-conditions/eating-disorders-ks4-article/
Eating disorders refer to unhealthy eating habits, which cause psychological and physical damage but can be treated in many cases.

In vitro fertilisation treatment (IVF)
/explore/discover/in-vitro-fertilisation-treatment-ivf/
In vitro fertilisation is a fertility treatment which stimulates the ovaries to produce multiple eggs which are collected and fertilised by sperm outside of the body in the laboratory to create embryos. One or two of which are then selected and transferred back to the womb in order to result in pregnancy.

Eating disorders - symptoms and causes
/explore/discover/eating-disorders-symptoms-and-causes/
Eating disorders refer to unhealthy eating habits, which cause psychological and physical damage but can be treated in many cases.

Klinefelter's syndrome
/endocrine-conditions/klinefelters-syndrome/
Klinefelter syndrome is a genetic condition that can only affect boys / men and occurs due to the presence of one (or more) extra X chromosomes. The condition is typically characterised by tall stature, reduced fertility and development of breast tissue (gynaecomastia), although in some men there may be no clinical features other than reduced or absent sperm count.

Prader-Willi syndrome
/endocrine-conditions/prader-willi-syndrome/
Prader-Willi syndrome is a genetic disorder leading to excess hunger and obesity, lack of some hormones, developmental delay, learning difficulties and behavioural problems.

Why do we need hormones?
/explore/discover/why-do-we-need-hormones/
Over 50 hormones have been identified in the human body, but there are likely more to be discovered.

What is a hormone?
/explore/discover/what-is-a-hormone/
Hormones are chemical messengers. They are nearly always made by endocrine glands, and they travel in the blood. Their signals can affect different organs and tissues in different ways. Hormones are especially important for growth, metabolism, appetite, puberty, and sexual reproduction.

Have I got a thyroid problem?
/explore/resources/podcasts/have-i-got-a-thyroid-problem/
Do you ever feel tired and sluggish, and find yourself putting on a few pounds? Or perhaps you’re anxious, irritable, and no matter how much you eat, you're just not gaining weight? Does Dr Google think your thyroid is to blame for all your woes?

Multiple endocrine neoplasia type 1
/endocrine-conditions/multiple-endocrine-neoplasia-type-1/
Multiple endocrine neoplasia type 1 is a rare inherited disease, which can result in tumours in the pituitary and parathyroid glands, and pancreas.

Will taking hormones make me taller?
/explore/resources/podcasts/will-taking-hormones-make-me-taller/
Ever wished that you could change your height? We investigate how hormones affect our height destinies, and what they have to do with the legend of the Irish giants.