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Tips Jun 04, 2024

The who's who of hormones: Here are the key players in puberty

Leah Farley, MD, Pediatrician 5 minute read

If you've spent time with a teenager, you've probably witnessed the hormonal mood swings that come with puberty. But, as it turns out, hormones aren't just responsible for changes in mood during puberty. Hormones are the ones running the show. 

Hormones are what trigger physical developments in a child that prepare them for adulthood as they age. The way these hormones work in the body can be quite different for boys (which we will use to refer to those who are born genetically male) than it can for girls (which we will use to refer to those who are born genetically female). 

Certain hormones work closely together — some trigger others and some work together with others. So, understanding their roles can be confusing. Here's a brief, high-level summary of what hormones are surfacing during your child's development and what they're responsible for. 

Gonadotrophins kick things off

When a child begins puberty, the child's brain begins to function more like an adult's brain. To do this, it starts to produce more of what's called a gonadotrophin-releasing hormone (GnRH). This hormone triggers the release of multiple other hormones that are responsible for the bulk of an adolescent's development. 

As the body produces more GnRH, it also starts to produce more follicle stimulating hormone (FSH) and luteinizing hormone (LH). These hormones are what drive the development of reproductive organs in a child. In girls, these hormones are what will eventually control and regulate menstruation. In boys, these hormones increase the size of the sexual organs and begin to aid in the development of sperm. 

FSH and LH also trigger additional hormones — like testosterone and estrogen — that help with other parts of the development. Boys will rely more heavily on testosterone for their development, and girls will rely more heavily on estrogen and progesterone. 

Testosterone drives male development

Testosterone causes a lot of physical changes in boys during puberty. Testosterone leads to the growth of hair in boys in the pubic area, in the armpits and on the legs and arms. Thanks to testosterone, boys also grow taller, put on weight and add muscle mass. Changes in testosterone levels can also result in stronger body odors and increases in acne during this time. Testosterone plays a role in girls' development, too, but not as big of a role as it does in boys' development.

Estrogen and progesterone cause most physical changes in females

Estrogen and progesterone work together to develop a girl's body and transition it into a woman's body, doing things like changing a girl's body composition by redistributing fat to the hips and breasts. Increased levels of these hormones also cause a girl's uterus to change shape and grow in length and thickness, preparing it for childbirth. Boys will also make estrogen, as this is the hormone necessary to cause bones to grow and therefore responsible for the growth spurt that adolescents go through during puberty. Due to the estrogen needed to grow tall, some boys will have breast development during their growth spurt, but don’t worry, that is generally mild and almost always resolves once they finish puberty.

Look out for hormonal issues

When hormones are doing their job, your child progresses in their development. However, if your child's body doesn’t produce hormones properly, you may see some negative effects for your child like hair loss, dry skin, fatigue, or emotional symptoms like irritability, anxiety or excessive nervousness.

Hormones can also activate at the wrong time, causing abnormal pubertal development. If your female child starts to experience signs of puberty before the age of 8 or your male child starts to show pubertal changes before the age of 9, you should discuss with your doctor if any further evaluation is needed. 

There are also conditions that can delay puberty. If your female child is over the age of 13 and has not started to have breast development or your male child is over the age of 14 without any indication of puberty, you may want to discuss this with your child’s doctor. If you think your child is experiencing a hormonal issue, consult your child's doctor. They can help determine if this is an issue and determine if any further evaluation or treatment is necessary.

Hormones can wreak havoc on emotions

Hormone levels can fluctuate quite drastically as the body learns to regulate these new changes. This fluctuation is what can cause mood swings for a child experiencing puberty. While increased intensity of emotions like sadness, loneliness or irritability can be normal for a period of time, if you're noticing drastic, prolonged changes in your adolescent's mood, it may be worth looking into a bit more. It's possible that a more serious mental health condition is being masked by the emotional distress of puberty. The best way to know for sure is to talk more to your child and seek help if needed. 

Body changes associated with puberty can also be very challenging for some children. For children who feel that their genetic sex does not match their gender identity, puberty can be a time of distress. For children with developmental differences who struggle with hygiene or understanding body changes, it can be difficult for parents to help the child understand and properly care for their changing body. When there are concerns, it is always best to talk with your doctor to see if there are options for hormonal regulation that might be beneficial to the child. 

Puberty is not always an easy time in a child's development, but it's a critical one. It's important to reassure your child that what they're going through is normal and everyone experiences it. But, if you have any worries or concerns about your child, you can always reach out to their doctor for support and guidance. 

Children's Wisconsin Resources

Children’s Wisconsin has more than 20 primary care offices conveniently located throughout the Milwaukee area and southeast Wisconsin. Find a pediatrician near you. View more articles from Leah Farley, MD

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