Pregnancy and Analgesia
The UK teratology information service – uktis – has an excellent website http://www.uktis.org/ which gives up to date information about the safety of drugs in pregnancy, addressing all aspects of concern including risk of congenital anomaly, spontaneous abortion, intrauterine death, neurodevelopmental impairment, preterm delivery and problems in the early postnatal period.
There is also a link to http://www.medicinesinpregnancy.org/ which has patient information leaflets.
Adverse effects on maternal and fetal outcome due to the underlying maternal condition for which paracetamol or other analgesia is used should be considered when interpreting pregnancy safety data. Some studies have indicated that a rise in maternal core body temperature of 1.5°C may be associated with teratogenicity or, in the first trimester of pregnancy, an increased risk of neural tube defects in the offspring, however other data are conflicting. Severe pain, if inadequately treated, may also impact on maternofetal outcome through alteration of both maternal cardiovascular function and uteroplacental perfusion.
Paracetamol A study of mice suggesting that long term use of paracetamol during pregnancy reduced levels of testosterone and resulted in undescended testes in male babies has not been confirmed in human studies.
Nonsteroidal anti-inflammatory drugs should not be given after 30 weeks due to the risk of premature closure of the ductus arteriosus.
Opioids. The American College of Obstetricians and Gynecologists produced a committee opinion in 2012 on “Opioid abuse, dependence and addiction in pregnancy”[1] which also addresses issues on prescribed opioid use in pregnancy. An association between first trimester use of Codeine and congenital heart defects was found in three out of four case-control studies. Previous reports did not show an increased risk of birth defects after prenatal exposure to Oxycodone or pethidine. One retrospective study observed an increased risk of some birth defects with the use of prescribed opioids by women in the month before or during the first trimester of pregnancy.[2] However, methodological problems with this study exist, and such an association has not been previously reported.
If given throughout pregnancy either for pain relief or for the management of drug addiction, opioids may result in neonatal abstinence syndrome (NAS) so the infant should be monitored closely for opioid withdrawal symptoms.[3,4] These may be mitigated by breastfeeding. Tramadol appears to provoke a particularly pernicious withdrawal syndrome [5].
Contact the pain team for more support and advice. Useful Contact Details within OUH