BOSTON — Nationwide, the number of pregnant women using heroin, prescription opioids or medications used to treat opioid addiction has increased more than five times and it’s expected to keep rising.

With increased opioid and heroin use, the number of babies born with severe opioid withdrawal symptoms has also spiraled, leaving hospitals scrambling to find better ways to care for the burgeoning population of mothers and newborns.

Among the most important principles is that expectant mothers who are addicts should not try to quit drugs cold turkey because doing so could cause a miscarriage. Trying to quit opioids without the help of medications also presents a high risk of relapse and fatal overdose.

Until the opioid-abuse epidemic took hold about eight years ago, most hospitals saw only one or two cases a year of what is known as neonatal abstinence syndrome. Now, a baby is born suffering from opioid withdrawal every 25 minutes in the U.S., according to the National Institute on Drug Abuse.

When a pregnant woman uses drugs or alcohol during pregnancy, some of the substances travel through the placenta to the baby. In many, but not all, cases, exposure to opioids during pregnancy can cause the fetus to develop drug dependence. When the umbilical cord is cut at birth, the newborn is abruptly disconnected from its supply of opioids and can suffer withdrawal symptoms.

At Boston Medical Center in the city’s South End, heroin addiction during pregnancy is not new. A specialized team of obstetricians, addiction medicine providers and counselors known as Project Respect has been treating pregnant drug users here for more than 30 years.

Now, dozens of hospitals and health clinics are gearing up to provide the same kind of specialized treatment for a rapidly rising number of pregnant drug users and their newborns.

Although painful, newborn withdrawal symptoms, which include muscle cramps, tremors, diarrhea, vomiting, sleep problems and sometimes seizures, are not life-threatening and have not been shown to cause health problems or developmental deficiencies later in life. The condition can be treated with small doses of morphine and subsides within three weeks.

Last year, a federal law was enacted — the Protecting Our Infants Act — authorizing the U.S. Centers for Disease Control and Prevention to work with states to collect data on the prevalence of babies born with opioids in their bloodstream. It also calls on the U.S. Department of Health and Human Services to develop recommendations for the best way to prevent and treat drug use during pregnancy.

For now, here’s what major medical organizations — including the American College of Obstetricians and Gynecologists, the American Society of Addiction Medicine and the American Academy of Pediatrics — agree on:

The standard of care for pregnant women using prescription painkillers or heroin is maintenance treatment with opioid addiction medications methadone or buprenorphine. Abstaining from drugs without medication is not recommended because of the high risk to the mother of relapse and overdose.

Although methadone and buprenorphine expose the fetus to low doses of opioids, the risk to the newborn of withdrawal symptoms is far outweighed by the risk of a fatal overdose when pregnant women receive no treatment or attempt to abstain from drugs without medication.

Abruptly quitting opioids in the first and third trimesters of pregnancy can cause harm to the fetus, including miscarriage and stillbirth, and is not recommended. Even in the second trimester, specialists agree that the risk of relapse outweighs any potential benefit to the fetus of lowering the dose of addiction maintenance medications or discontinuing their use.

Advocates for newborns, including the March of Dimes, agree with major medical organizations on the use of opioid treatment medication. But they argue more data and better research are needed to determine the best approach to treating opioid addiction during pregnancy.

“With pregnant moms, we’re weighing the high risk of death from overdose against the risk to the newborn of treating pregnant women with low dose opioid maintenance,” said Dr. Siobhan Dolan, medical adviser to the March of Dimes.

With more research, she said, “we would be in a better position to consider abstinence and behavioral health counseling for some women.” And that could result in healthier babies.