In pregnancy
The risk of HIV acquisition is increased and the viraemia that occurs during HIV seroconversion leads to an increased risk of intrauterine HIV transmission.86 Timely specialist consultation is recommended, however PEP should not be delayed or withheld in people who are pregnant.
- If three-drug PEP is indicated either dolutegravir 50 mg daily or raltegravir 400 mg twice daily can be used (see Table 3)
- All patients with the potential to conceive presenting for PEP should:
- have a contraceptive and reproductive history taken to assess risk of pregnancy
- be offered pregnancy testing (ideally serum beta hCG)
- be offered emergency contraception if indicated (refer to RACGP Australian Family Physician. Emergency contraception: oral and intrauterine options)87
- When indicated, follow-up pregnancy testing should occur three to four weeks post-exposure
- Points to discuss when initiating HIV PEP in a person who could be or is pregnant:
- risks and benefits of HIV PEP in pregnancy
- risk of vertical transmission and higher risk of HIV acquisition in pregnancy
- if indicated, counselling on pregnancy options, or discussion of long-term contraceptive options.
In lactation
Timely specialist consultation is recommended however PEP should not be delayed or withheld in people who are lactating and nursing infants.
Antiretrovirals taken during lactation can enter breast milk and be ingested by the infant. The antiretroviral exposure to the infant varies with several factors, including stage of lactation, dosage taken by the birth parent, pharmacokinetics of drugs and nursing pattern of the infant.88
Most published experience with tenofovir disoproxil fumarate is for HIV therapy and prophylaxis. Exposure of the nursing infant to tenofovir is negligible in both HIV-positive and HIV-negative birth parents taking HIV prophylaxis or treatment for HBV infection.89
Emtricitabine has been relatively well studied during lactation when used as HIV PrEP. Infants receive only about 0.5% of a therapeutic dose of emtricitabine and with long-term use of emtricitabine by the birth parent, these infants usually have undetectable blood concentrations.90
For lamivudine, a meta-analysis reported exposure of the exclusively lactation-fed infant to 10% of the weight-adjusted infant dose.91
In a randomised trial of dolutegravir or efavirenz-containing antiretroviral therapy in the third trimester and until two weeks post-partum, lactation feeding led to significant plasma exposures in the infant, despite low plasma dolutegravir concentrations.92
For raltegravir, the levels in milk are low and blood levels in a lactation-fed infant were barely detectable, thus there does not appear to be any concern for raltegravir in human milk.93
For further information on use of antiretrovirals in pregnancy and lactation refer to the Australian Commentary on the US DHHS Guidelines for the use of Antiretroviral Agents in HIV-1 Infected Adults and Adolescents.
