Most pregnant women will put aside their "bad habits" during pregnancy for fear of harming their health or the health of their unborn child. Most, but not all. The thought of going nine months without alcohol, tobacco or marijuana is apparently just too much to endure for some expectant mothers, so they go right on using right through their pregnancy.

U.S. Surgeon General Jerome Adams says marijuana use among pregnant women actually doubled from 3.4 percent to 7 percent between 2002 and 2017, prompting the first federal bulletin about marijuana use in some 30 years. Adams says marijuana use during pregnancy could lead to low birth weight and might disrupt fetal brain development.

Getty Images / U.S. Surgeon General Jerome Adams

"No amount of marijuana use during pregnancy or adolescence is known to be safe. Until and unless more is known about the long-term impact, the safest choice for pregnant women and adolescents is not to use marijuana," Adams wrote. The bulletin says THC, the psychoactive component in marijuana, has been found in breast milk up to six days after marijuana use and could affect the newborn’s brain development.

More than half of states, including Massachusets, have legalized cannabis use in some form, despite it remaining illegal under federal law. This has contributed to a sharp increase in the use of the drug by expectant mothers and adolescents even as the use of alcohol by young people continued to decline.

The use of any non-prescribed or non-doctor-approved drug while pregnant is irresponsible and selfish. Kicking the habit is difficult but worth it in the long run. For help in changing your behavior while pregnant, consult with your doctor and or rely on friends for support.

Barry Richard is the host of The Barry Richard Show on 1420 WBSM New Bedford. He can be heard weekdays from noon to 3 p.m. Contact him at barry@wbsm.com and follow him on Twitter @BarryJRichard58. The opinions expressed in this commentary are solely those of the author.