Blood Test: Luteinizing Hormone (LH)enparentshttps://kidshealth.org/EN/images/headers/P-testLH-enHD-AR1.gifA luteinizing hormone (LH) test measures the level of this hormone in the bloodstream. LH plays an important role in sexual development.luteinizing hormones, fsh, LH, hormones, blood tests, diagnostic tests, puberty, precocious puberty, early puberty, hormone tests, estrogen, testosterone, sexual development, testes, ovaries, pituitary gland, hypothalamus, assays, needles, medical tests, glands, pituitary gland, lutinize, leteinize, lewtinize, loutinize, lutinizing, luteinizing, bloodstream, gonadotropin-releasing hormone, GnRH, gnrh, gonads, gonadotropin, follicle stimulating hormones, follicles, late puberty, delayed puberty, development10/06/200811/22/201911/22/20198b1291d2-4e1d-485c-b485-97ef7f005723https://kidshealth.org/ws/RadyChildrens/en/parents/blood-test-lh.html/<h3>What It Is</h3> <p>Luteinizing hormone (LH) plays an important role in sexual development and is produced by the pea-sized pituitary gland in the brain. An LH test measures the level of this hormone in the bloodstream.</p> <p>In kids, LH levels are high right after birth, but then fall, remaining low until puberty approaches (usually between ages 10 and 14). At this time the hypothalamus, an almond-sized area of the brain that links the nervous system with the hormone-producing endocrine system, releases gonadotropin-releasing hormone (GnRH) that starts the changes of puberty. GnRH signals the pituitary gland to release two puberty hormones into the bloodstream: LH and follicle stimulating hormone (FSH).</p> <p>In boys, LH and FSH work together to get the testes to begin producing testosterone, the hormone responsible for the physical changes of puberty and the production of sperm.</p> <p>In girls, LH and FSH prompt the ovaries to begin producing the hormone estrogen, which causes a girl's body to mature and prepares her for menstruation.</p> <p>Because LH and FSH work so closely with each other, doctors often perform these tests together, as well as tests for testosterone (the major male sex hormone) and estradiol (a form of estrogen, the major female sex hormone). Taken together, the results can often provide a more complete picture of a child's sexual maturation, and the well-being of the glands that produce these hormones.</p> <h3>Why It's Done</h3> <p>Doctors may order an LH test if a boy or girl appears to be entering puberty much earlier or much later than expected. High levels are associated with precocious (early) puberty, while low levels may indicate a delay in sexual development.</p> <p>The test may also be used to check for damage or disease of the testes or ovaries, pituitary gland, or hypothalamus.</p> <p>In adults and teens, LH levels can also help doctors evaluate fertility issues and menstrual problems.</p> <h3>Preparation</h3> <p>No special preparations are needed for this test. On the day of the test, having your child wear a T-shirt or short-sleeved shirt can make things easier for the technician drawing the blood.</p> <h3>The Procedure</h3> <p>A health professional will clean the skin surface with antiseptic, and place an elastic band (tourniquet) around the upper arm to apply pressure and cause the veins to swell with blood. Then a needle is inserted into a vein (usually in the arm inside of the elbow or on the back of the hand) and blood is withdrawn and collected in a vial or syringe.</p> <p>After the procedure, the elastic band is removed. Once the blood has been collected, the needle is removed and the area is covered with cotton or a bandage to stop the bleeding. Collecting the blood for the test will only take a few minutes.</p> <p><img class="left" src="https://kidshealth.org/EN/images/illustrations/bloodTest-400x760-rd1-enIL.gif" alt="Blood draw showing tourniquet, syringe, and butterfly needle, as described in the article text." name="974-031609_BLOODTEST_RD7.GIF" /></p> <h3>What to Expect</h3> <p>Collecting a sample of blood is only temporarily uncomfortable and can feel like a quick pinprick. Afterward, there may be some mild bruising, which should go away in a few days.</p> <h3>Getting the Results</h3> <p>The blood sample will be processed by a machine, and results are usually available in a couple of days.</p> <h3>Risks</h3> <p>The LH test is considered a safe procedure. However, as with many medical tests, some problems can occur with having blood drawn, like:</p> <ul> <li>fainting or feeling lightheaded</li> <li>hematoma (blood accumulating under the skin causing a lump or bruise)</li> <li>pain associated with multiple punctures to locate a vein</li> </ul> <h3>Helping Your Child</h3> <p>Having a blood test is relatively painless. Still, many kids are afraid of needles. Explaining the test in terms your child can understand might help ease some of the fear.</p> <p>Allow your child to ask the technician any questions he or she might have. Tell your child to try to relax and stay still during the procedure, as tensing muscles and moving can make it harder and more painful to draw blood. It also may help if your child looks away when the needle is being inserted into the skin.</p> <h3>If You Have Questions</h3> <p>If you have questions about the LH test, speak with your doctor.</p>Análisis de sangre: lutropinaEs posible que los médicos soliciten un análisis de lutropina si un niño parece estar ingresando en la pubertad mucho antes o mucho después de lo esperado.https://kidshealth.org/ws/RadyChildrens/es/parents/blood-test-lh-esp.html/4628e82d-e42a-4fab-ac49-47d8fa939eb5
Blood Test (Video)These videos show what's involved in getting a blood test and what it's like to be the person taking the blood sample.https://kidshealth.org/ws/RadyChildrens/en/teens/video-bldtest.html/267eef2d-8579-44db-adcb-641db49d0ec0
Blood Test: EstradiolEstradiol is the most important form of the hormone estrogen. Doctors may order an estradiol test if a girl appears to be entering puberty earlier or later than expected, or to evaluate menstrual problems.https://kidshealth.org/ws/RadyChildrens/en/parents/blood-test-estradiol.html/3ef3d518-8bd4-41ee-9548-91c623bfb2f0
Blood Test: Follicle Stimulating Hormone (FSH)Follicle stimulating hormone (FSH) plays an important role in sexual development. An FSH test to measure the level of FSH in the bloodstream may be done if a boy or girl appears to be entering puberty earlier or later than expected.https://kidshealth.org/ws/RadyChildrens/en/parents/blood-test-fsh.html/abfb1d2c-e891-4cc6-b0d9-6b30b8ca2f37
Blood Test: ProlactinA prolactin test can help diagnose prolactinoma, a usually benign tumor of the pituitary gland, irregular menstrual periods, thyroid or adrenal gland dysfunction, and other problems.https://kidshealth.org/ws/RadyChildrens/en/parents/test-prolactin.html/4645e473-e052-447c-87e9-3b8a15094164
Blood Test: TestosteroneA testosterone blood test may be done if a boy appears to be entering puberty earlier or later than expected, or to check for damage or disease of the testes or ovaries, adrenal glands, or pituitary glands.https://kidshealth.org/ws/RadyChildrens/en/parents/test-testosterone.html/07fd8cfb-73df-4d2c-84f8-a4218911f98f
Delayed PubertyConcerned about your growth or development? Puberty can be delayed for several reasons. Luckily, doctors usually can help teens with delayed puberty to develop more normally.https://kidshealth.org/ws/RadyChildrens/en/teens/delayed-puberty.html/26226dd1-992c-4cb8-aeb0-cb8b61d4fa84
Endocrine SystemThe endocrine system influences almost every cell, organ, and function of our bodies. It is instrumental in regulating mood, growth and development, metabolism, and sexual function, among other things.https://kidshealth.org/ws/RadyChildrens/en/teens/endocrine.html/7572f55a-2090-4b77-b6d1-74740e26934d
Getting a Blood Test (Video)A blood test might sound scary, but it usually takes less than a minute. Watch what happens in this video for kids.https://kidshealth.org/ws/RadyChildrens/en/kids/video-bldtest.html/13ac3212-6f5c-4741-8827-24b1c5a9549e
Precocious PubertyPrecocious puberty - when signs of puberty start before age 7 or 8 in girls and age 9 for boys - can be tough for kids. But it can be treated.https://kidshealth.org/ws/RadyChildrens/en/parents/precocious.html/c7e061da-52f4-406d-9a3f-c012dff0e981
Sexual DevelopmentBig physical and emotional changes happen during puberty and the teen years. These articles can help you become a source of information, comfort, and support for your kids.https://kidshealth.org/ws/RadyChildrens/en/parents/development-foyer.html/6d961459-9968-4bc2-bf56-c25790e065e4
Understanding PubertyPuberty was awkward enough when you were the one going through it. So how can you help your kids through all the changes?https://kidshealth.org/ws/RadyChildrens/en/parents/understanding-puberty.html/527eb4ba-e207-497b-b5a9-0a57e6624675
Word! PubertyEveryone goes through puberty, even though it sometimes feels like you're the only one!https://kidshealth.org/ws/RadyChildrens/en/kids/word-puberty.html/b343e4cb-c661-4f50-955d-ccd2b9a4a736
Your Endocrine SystemThe endocrine system produces hormones, which are needed for proper body function and growth. Find out more in this article for kids.https://kidshealth.org/ws/RadyChildrens/en/kids/endocrine.html/e74a807b-43a3-42cf-971a-fcb15443e5e5
kh:age-allAgesOrAgeAgnostickh:clinicalDesignation-pathologykh:genre-articlekh:primaryClinicalDesignation-pathologyMedical Tests & Examshttps://kidshealth.org/ws/RadyChildrens/en/parents/system/medical/b5327501-2bda-444b-8df1-a1af15af79cbhttps://kidshealth.org/EN/images/illustrations/bloodTest-400x760-rd1-enIL.gif