Is delayed puberty inherited? Could I speed it up in some way?

Last updated on September 25, 2020



I am almost 20 years old and I have several questions about pubertal development in boys. I am currently at the beginning of Tanner stage 4 and I officially started puberty at the age of 17 and 9 months (first testicular and scrotal enlargement, growth spurt, penile growth, secondary sex characteristics, etc.). I was wondering whether there could be any link between the fact that my father went through puberty between the ages 18-22, my aunt (his sister) had her first period at 21 and one of my mum’s first degree cousins got hers at 19 (all these relatives became normal adults eventually, but several years later than what it is considered average) and my delayed maturation.

I want to ask this because I’ve spent most of my teen years in great nervousness, thinking that my penis would end up on the small side.  I have been masturbating since the age of 12.5, hoping this would help me mature, but, of course, it didn’t help me look more like adults, grow facial and body hair, deep voice, penile growth until a late age.

My question is why do some people deserve to live such a nightmare, finally maturing sexually and physically in their old age, while others look at 15 the same as I do at 20? Should I have behaved in a particular way during my teen years in order to have altered my disgraceful pace of maturation? Should I have had sex from an early age or misbehaved?

I am also, by definition, in the stage when considering becoming sexually active, and I have some questions about penis size. The first one is about where you do inherit this size from? Is it from the father’s side (father, paternal grandfather, great grandfather, etc.) of the maternal grandfather or other men from the mother’s side? I heard that some women only consider a 10-12 inch penis as being attractive (and lots of boys and men brag about being this size), while I am just a shy of 6.9 inches (measured along the top of the shaft, with a tape measure, non bone-pressed). I honestly doubt anyone in my family is 10-12 inches, supposedly correctly measured as I have described before, not even my paternal great grandfather and grandfather, who are considered “the donkeys of my family”.

Another question would be whether your penis size is linked to your ego or to having sex from an early age. I mean the more you misbehave and brag during your teen years and the earlier you start having sex, the bigger it will be as an adult. I am rather a shy and calm person and I have always thought that I was doomed to have a small penis due to this fact. What should I do to make it bigger?

I don’t understand why some girls demand such things, since I care very little about their bra size or weight. I could also shout that for me a girl is not attractive unless she wears at least D cup in her bra (since women in my family are D and C cups, with my mum being large D, so I wouldn’t spoil my genes with a flat chest) but for me, it matters more to be the right person.

I was also brought up in a religious environment and respected God’s law to wait for sex until you get married, so I refrained from this during my teen years. The only “reward” I get is having a smaller penis, looking several years younger than boys around me, and living in constant fear that I will no longer develop since everybody nowadays tells you that you stop developing by the time you are 17 (fortunately not in my case).

I grew up with the idea that boys are not fully mature until their mid-twenties and not 16-17. Are you fully developed when you grow a full beard and a thick coat of body hair (men on my mother’s side are quite hairy) and I started having belly and chest hair (although still pretty fine), a goatee and sideburns, visible arm and leg hair, thick hair in the pubic region and under the arms? I worry that I will never become a normal adult and I won’t be able to lead a normal sex life a few years from now when I will start a family, due to my impaired development. What should I do in order to become fully physically mature? I would be grateful for any help with answering these life-long questions that have severely damaged my self-esteem during my teen years.

Thank you for your time and assistance.


It appears that you had been given some incorrect information that caused most of your worries. Most growth and development information available discusses the average or typical teenager. You are a classic late bloomer; in fact, you are on the far end of the scale for late bloomers. Therefore, most of the typical information and rules of thumb don’t apply to you.

Since penis size has been a big concern to you, the typical range for the length of an erect penis is 3 to 8 inches. The average size is 5.2 inches long []. Most women report preferring a smaller penis because it is more comfortable. Therefore, the information you were told about the penis size was bogus.

Growth of the body is determined by your genes, not by what you do. About the only way a person can impact their growth is to not eat properly which will reduce their growth to less than its potential. You can’t make your nose, ears, or penis grow bigger than its potential by doing things to it or by eating certain things.

Masturbation doesn’t impact your maturation. Sexually sinning doesn’t impact your maturation. You have a “chicken and egg” problem where you are not considering which came first. People who mature sooner will naturally masturbate sooner because they are producing semen earlier in life than you. You are assuming the effect is the cause instead of the other way around. Boys who mature sooner are tempted with sexual sin sooner and since they are younger are more likely not to think of the consequences of their actions. Again, sinning didn’t make them mature faster. You following God’s laws did not make you mature later. I know many boys who matured at a typical rate and did not have sex until their wedding night.

There is strong evidence that delayed puberty is inherited from your parents. The likelihood of a male inheriting delayed puberty is stronger than females, but not by much [NIH]. It doesn’t appear that inheriting delayed puberty is more prevalent from a father or mother. Having both parents having delayed puberty makes it more likely that a child will have delayed puberty. What makes studying delayed puberty complicated is that there are multiple causes. Only about half of delayed puberty cases are inherited. Others are caused by diseases.

Depending on the cause, there are some hormones an endocrinologist can given a boy who is delayed in his puberty to start the sequence of change earlier, but generally, most doctors are reluctant to interfere when the delay is natural and not caused by a disease for fear of causing additional problems.

In males, the stages of development are about two years long for each stage. You hit stage 2 (the start of puberty) at the age of 17 and are now at stage 4 (the last phase of development) at age 20 — about 1.5 years for stages 2 and 3. Thus, you will probably be done growing in height by age 22. However, some secondary characteristics, such as body and facial hair continue into stage 5. You might not get a full beard or lots of body hair until after you are 25.


Dear Mr Hamilton,

Thank you so much for your email. It has really made a difference for me. I think that it is tough to watch most people around you growing and developing, while your body is not cooperating until others have finished developing.

I have recently learned that my paternal grandmother also menstruated for the first time when she was 21 (and I was unwittingly bragging at school that at 63 her hair was still almost entirely black), so no wonder why I got a bad deal in the timing of puberty. However, my mother went through puberty between 8-13, her brother started at 11 and my maternal grandmother also started at 11 and it seems I got the short end of this genetic lottery.

I am glad to hear that you do not have to sin sexually or misbehave in order to become a normal man or have I don’t know what sort of good luck (which I usually don’t have). It seems that I am going through the same sequence of changes as it states in theory, but 5 years later than average. I estimate that I should be fully developed between ages 23-25, as my father was (he stopped growing taller at age 22.5, but continued to mature sexually for a couple more years).

I am extremely grateful for the help I received, and I hope that my situation may serve as an example for other people who encounter the same condition as I do. Thank you for your time and assistance.