It is important to prescribe the correct analgesic during pregnancy to optimize the maternal and neonatal outcome. Inadequate pain-relief in pregnancy leads to anxiety and psychological strain for mother and affects her ability to provide care for her newborn–note the recent Scientific Impact Paper published December 12, 2018, in the BJOG.
The paper was developed for the Royal College of Obstetricians and Gynaecologists (RCOG) by a group of eminent doctors and researchers following the advisory issued by the Medicines and Healthcare products Regulatory Authority (MHRA) and European Medicines Agency (EMA) on the use of codeine in pregnancy because of neonatal mishap and three other fatalities in children.
The findings reflect current NHS guidance on the use of medical pain relief options in pregnancy and during breastfeeding. However, the guidance does not address the concerns for Intrapartum analgesia.
Women often need analgesic during the antenatal period for a headache, backache, and pelvic pain.
Non-pharmacological interventions like relaxation, adequate rest, heat, massage, acupuncture, posture training, physiotherapy, and exercise should be considered before starting any drugs. Notably, all drugs should be avoided during early pregnancy to prevent the teratogenic effects of drugs during the organogenesis period (4-10 weeks).
Paracetamol
Paracetamol remains the drug of choice for pain relief throughout pregnancy, although few studies have demonstrated an increased incidence of childhood asthma, behavioral problems, and a delay in gross motor and communication development in children with long‐term antenatal exposure.
NSAIDs
Studies have failed to demonstrate any clear association between congenital malformations and the use of nonsteroidal anti-inflammatory drugs (NSAIDS) in early pregnancy.
However, there is conflicting evidence regarding the use of NSAIDs and risk of miscarriage in the first trimester. Therefore, NSAIDs be avoided during pregnancy, especially during the first trimester. They should only be used when absolutely necessary in conditions such as a migraine or ankylosing spondylitis, that too in lowest possible dose and for the shortest duration of time.
Use of NSAIDs should be avoided after 30 weeks of gestation because it can cause neonatal pulmonary hypertension and premature closure of the ductus arteriosus. NSAIDs also reduce fetal renal blood flow leading to decreased urine production and causing oligohydramnios.
The review says that opioid analgesic should only be used under the care of health professional in the lowest possible dose and shortest amount of time. It should be used when paracetamol has been ineffective. Limited data available does not point towards increased risk of fetal toxicity.
However, if used around the time of labor, it may lead to neonatal respiratory depression and if used for prolonged time cause neonatal withdrawal symptoms and maternal dependence.
The guidelines also highlighted the critical difference between the use of codeine and DHC during breastfeeding. If stronger analgesia is required, Dihydrocodeine (DHC) is much safer to use as compared to codeine which causes fetal toxicity.
Low doses of dihydrocodeine in combination with paracetamol can be bought over the counter but regular use of any opioid beyond 3 days should be under close medical supervision.
Gabapentin
Gabapentin is mostly used in chronic pain syndrome, and only a few studies have been done on the use of gabapentin in pregnancy. Evidence does not link the use of the drug to a particular birth defect; however, women are advised to take high doses of folic acid before conception and during the first trimester.
Gabapentin use in pregnancy after 30 weeks is very limited, and if used around the time of delivery it may lead to neonatal withdrawal syndrome.
Analgesics at the time of discharge
Majority of women who require analgesics at discharge should be prescribed paracetamol or ibuprofen. If stronger analgesics are required (cesarean delivery), women should be sent home with a limited supply of DHC. Tramadol is only given if a woman is intolerant to DHC.
Dr Dina Bisson, consultant obstetrician and gynecologist at the North Bristol NHS Trust and the lead authors of the guidance said: "It is absolutely essential that pain is managed appropriately during pregnancy and breastfeeding. Many women may develop headaches, lower back pain, and pelvic pain during pregnancy and breastfeeding, while others may have chronic conditions, where pain management is necessary.
"If pain is not adequately managed, this can have a negative impact on a woman's physical and mental wellbeing.
