Are muscle relaxers safe during pregnancy?

What does the evidence say about muscle relaxers during pregnancy?

1. Among 33,615 birth defect cases and 13,110 controls, cyclobenzaprine use around conception was rare (0.15% of cases and 0.07% of controls) and showed higher odds for seven defects, including cleft palate and several heart defects. 1
2. The authors of that cyclobenzaprine analysis describe their estimates as unadjusted, imprecise, and hypothesis-generating, and say the findings warrant confirmation rather than a conclusion. 1
3. Oral baclofen during pregnancy can cause temporary symptoms in newborns soon after birth, which have included seizures, tremors, muscle rigidity, excessive drowsiness, and feeding difficulty. 2
4. It is not known whether baclofen raises the chance of birth defects above the background rate, and studies on miscarriage and preterm delivery have not been done. 2
5. Acetaminophen carries far more pregnancy evidence than any muscle relaxant, and many healthcare providers and organizations still consider it the pain reliever and fever reducer of choice in pregnancy. 3

Is muscle relaxers safe in each trimester?

• First trimester. Organ formation happens in this window, which is why the cyclobenzaprine analysis looked specifically at the month before conception through the third month. If you were already on a muscle relaxant when you found out, call your prescriber before changing the dose yourself. Stopping abruptly is its own decision.
• Second trimester. Back, hip, and pelvic pain often peak here, and this is where prescribers weigh a short course against physical therapy, a support belt, and acetaminophen. Ask which specific drug, what dose, and for how many days. An open-ended prescription is worth questioning during pregnancy.
• Third trimester. Sedation becomes the practical problem late, both day to day and around delivery. Oral baclofen has been linked to temporary symptoms in newborns soon after birth. Whatever you are taking, your obstetric team should have it on the list well before your due date, not on the day.