Wait — What Is Minipuberty & Why Is It Important For Reproductive Health? 

According to environmental and reproductive epidemiologist Shanna Swan, Ph.D., we would do well to maintain ongoing conversations about fertility. That's because, as it turns out, even experiences you have growing up can affect your reproductive health later on. 

Specifically, your body goes through a few developmental periods that can have downstream effects as you age: "Sensitive periods are important—those are the periods when the body is rapidly dividing or growing," she says on the mindbodygreen podcast. "Obviously prenatal is very important, and then soon after birth [there's what's called] the minipuberty." Wait, what?

Here, Swan breaks down this developmental stage and why it's so important for reproductive health.

We did some more digging: Apparently, minipuberty occurs between birth and 6 months of age for boys and 2 years of age for girls, and it marks the development of various characteristics1 including the genital organs and fertility, body composition and growth, cognitive abilities related to speech, and potentially behavior—like perhaps emotional regulation in males.

A little sex ed. for you: Adolescent puberty happens when the hypothalamic-pituitary-gonadal (or HPG) axis becomes activated, which causes an increase in sex steroid hormones (which causes changes in body shape, an increase in body hair, et al.).

However, this activation actually occurs twice before that: once in utero and once in the first months of life. These first two activations do not bring about an increase in sex hormones, so they're categorized more generally as "endocrine puberties." They're just as important for reproductive health, but you don't necessarily see any changes to the body.

This minipuberty stage is important because it may allow for the early observance of and medical intervention in reproductive or sexual development disorders, if needed. As one study recounts, it forms a "platform for future fertility2," as it essentially sets the groundwork for your sex organs to mature and functions as a "window of opportunity" to evaluate the HPG axis—since that "window" is closed until you start puberty once again around 10 years later. More research is needed on the specific ways minipuberty affects future fertility, but it sure is a neat concept, no?

As of now, specific exposures and interventions that affect minipuberty is unknown. "I personally have not studied the effect of childhood exposures [to chemicals], and few people have studied the effect of childhood exposures on child health," notes Swan. But if she had to give marching orders, she would recommend teaching the young child good habits for reproductive health early on. "Eat healthy foods, avoid [phthalates], put their shoes at the door, and so on and so forth," she says. By doing so, "You're teaching them to protect their overall health and hopefully their reproductive health as well."

Aside from the riveting science lesson, Swan's mention of minipuberty is an important reminder that reproductive health isn't only relevant if you're thinking about having a baby. In fact, some fertility markers are relevant to health and longevity as a whole.