We’ve all become accustomed to a frequent label pinned on Maine — the oldest state in the country. We know the conversations that follow; we may have had them ourselves. Maine has a bad business climate; young people are fleeing, going to out-of-state schools and not coming back, there’s no future here for them. No wonder we’re so old.

Charles Colgan (former professor of public policy and management, USM’s Muskie School of Public Service) captured Maine’s problem succinctly: “It’s not that we are disproportionately old, it’s that we are disproportionately not young.”

A 2012 census estimate about Maine noted that no other state had a lower percentage of people between the ages of 15 and 44 (people born between 1968 and 1997).

What happened between 1968 and 1997 that led us to this national ranking? There are always two sides to a story, and the two sides to this one are birth rates and migration patterns.

In the 1970s and 1980s, Maine had one of the highest teen pregnancy rates in the country (ranked sixth). Alarmed at the potential for child abuse and neglect as well as dependency on government programs, legislators and state officials passed laws and dedicated state funds toward family life education in schools and improved access to preventive reproductive health care for teens. At the time, Maine was on the cutting edge of teen pregnancy prevention.

What followed in the next two decades, was the steepest decline in teen births in the country. Moreover, by the early 2000s, Maine’s teen abortion rates were about half the national average. Overall birth rates in Maine mirrored the declines among teens over those decades.

My husband certainly saw that in his medical practice. He began his family practice in 1980 in Coopers Mills, offering a full range of medical services, including deliveries. While very busy in the early years, he and his partners have seen a dramatic decline in births among their patient population during the past 35 years. The health center clinicians finally have stopped delivering babies and refer their patients’ pregnancies to the obstetricians in Augusta.

Another indicator of plummeting birth rates is the decline in Maine’s school-age population. Since the heyday of 1975 — Maine’s highest school enrollment ever — the number of schoolchildren has declined from 253,000 to 183,000 this year.

It’s abundantly clear that Maine’s dubious distinction of having the fewest 15- to 44-year-olds is not because that age cohort is fleeing the state in droves. What then is the impact of in- and out-of-state migration on the populations of young people living in our cities and towns?

In-migration in the 1970s, with back-to-the-landers, and 1980s, with young professionals, more than made up for declining birth rates in those decades. The trend slowed in the 1990s but picked up again dramatically in the early 2000s, when Maine’s in-migration rate ranked fifth in the country behind some very popular Sunbelt and Rocky Mountain states.

Contrary to what we’ve been grumbling about all these years, more people kept moving into Maine than moved out. Only in very recent years has that trend finally turned: Between 2007 and 2010 about 70,000 people moved into Maine and 75,000 moved out. That trend also was true for all other New England states except Massachusetts.

Unfortunately, it looks like this perfect storm of low birth rates and net out-migration will continue. Amanda Rector, Maine’s state economist, predicts no growth for Maine until at least 2030.

What must we do to see more young people holding up the bottom of our population pyramid? Short of instituting some bizarre governmental policy to encourage fertility — such as Denmark’s ad campaign, “Do It for Denmark,” or Russia’s, “Day of Conception” — we will have to accept that we cannot “birth” our way out of our predicament.

That’s where migration comes in. James Tierney, former attorney general of Maine, speaks pragmatically about the state’s need to welcome new residents, including immigrants, into this state if we are to have an adequate future workforce. Rep. Jared Golden, D-Lewiston, eloquently echoed this concern in a June 13 Bangor Daily News op-ed. This imperative flies in the face of shortsighted anti-immigrant policies enforced by the LePage administration.

While out-migration may not be our major demographic problem, it also must be addressed. We clearly need more jobs to keep and attract young people. But we also need affordable college education, student loan repayment programs, affordable housing, statewide high-speed Internet and accessible day care.

Birth rates got us into our “oldest state” dilemma, and in-migration will have to get us out.

Lisa Miller, of Somerville, is a former legislator who served on the Health and Human Services and Appropriations and Financial Affairs committees.