HIV IN PREGNANCY
A 36-year-old Nigerian woman who has lived in the UK for 8 years attends the antenatal clinic. She had a daughter by spontaneous vaginal delivery at term 12 years ago and a termination of pregnancy 9 years ago. She and her partner have now been trying to con- ceive for 4 years.
Her last menstrual period was 11 weeks ago. There is no significant gynaecological his- tory and last smear test was normal 2 years ago.
The woman saw the midwife for a routine antenatal booking appointment a week ago and no relevant past medical history was reported. All routine booking blood tests were accepted.
· What is the diagnosis?
· What is the next stage in management?
· What are the important points in the management of the pregnancy in view of the diagnosis?
The diagnosis is human immunodeficiency virus (HIV) infection. HIV screening in pregnancy is recommended for all women in the UK and the latest reported incidence was approxi- mately 0.5 per cent in inner London and less than 0.1 per cent for the rest of the UK. It is particularly prevalent in women from Africa (1.91 per cent compared with <0.5 per cent from all other areas). The vast majority of paediatric HIV cases in the UK result from mother-to-child transmission.
The low CD4 count suggests that this woman needs to commence treatment, but there are no AIDS-defining illnesses in the history.
The woman needs to be informed of the diagnosis and a second different diagnostic test performed to confirm the diagnosis. Most women choose to continue with their pregnan- cies, but she may still wish to consider the option of termination, as she is only 11 weeks’ gestation. She needs urgent referral to the genitourinary medicine specialist for further examination and investigation for any HIV complications. She will need to start Pneumocystis carinii prophylaxis in view of the low CD4 count, and she will also need antiretroviral treatment in view of the significant viral load.
Psychological counselling in relation to the diagnosis, the implications for her, her part- ner and her offspring (the fetus and her 12-year-old daughter) is very important.
Pregnancy does not adversely affect the HIV disease process. The important consideration is therefore the prevention of transmission from mother to child. Untreated, approxi- mately 25 per cent of infants of mothers with HIV will become infected. With appropriate measures, this is reduced to less than 5 per cent:
· elective Caesarean section
· avoidance of breast-feeding
· intravenous zidovudine to the mother prior to delivery (ideally for 4 h)
· oral zidovudine to the neonate for 6 weeks postnatally.
· More recently, vaginal delivery has been shown to have no effect on infant infection if the viral load is undetectable at the time of delivery.
Confidentiality is of paramount importance for women diagnosed antenatally with HIV, and coding systems in the hand-held obstetric notes can be helpful in alerting other medical staff to the diagnosis.