Hypothyroidism

• Levothyroxine dose needs to be increased during pregnancy, usually by at least 25-50 mcg (30-50%)
• Treatment is titrated based on the TSH level, aiming for a low-normal TSH level

Hypertension

• Women with existing hypertension may need changes to their medications
• Medications that should be stopped as they may cause congenital abnormalities:
  • ACE inhibitors
  • ARBs
  • Thiazide and thiazide-like diuretics
• Medications that are not known to be harmful:
  • Labetalol (other beta blockers may have adverse effects)
  • CCBs
  • Alpha blockers

Epilepsy

• Women with epilepsy should take folic acid 5mg daily from before conception to reduce the risk of neural tube defects
• Ideally, epilepsy should be controlled with a single anti-epileptic drug before becoming pregnant
• Levetiracetam, lamotrigine and carbamazepine are the safer anti-epileptic medication in pregnancy
• Sodium valproate is avoided as it causes neural tube defects and developmental delay
• Phenytoin is avoided as it causes cleft lip and palate

Rheumatoid arthritis

• Ideally, rheumatoid arthritis should be well controlled for at least three months before becoming pregnant
• Often the symptoms of rheumatoid arthritis will improve during pregnancy, and may flare up after delivery
• The treatment regime may need to be altered by a specialist rheumatologist before and during pregnancy:
  • Methotrexate is contraindicated, and is teratogenic, causing miscarriage and congenital abnormalities
  • Hydroxychloroquine is considered safe during pregnancy and is often the first-line choice
  • Sulfasalazine is considered safe during pregnancy
  • Corticosteroids may be used during flare-ups

Diabetes

Effect of pregnancy on diabetes

• Increases insulin requirements