Post partum complications in HIV-positive women

2 May 2004. Related: Pregnancy.

Polly Clayden, HIV i-Base

Mode of delivery for HIV positive women remains controversial. In the UK, the majority of deliveries to HIV positive women are by elective caesarean section that, performed before rupture of membranes, reduces the risk of mother to child transmission in women receiving no antiretrovirals or zidovudine monotherapy.

For women receiving HAART with a very low (<1000 copies) or an undetectable viral load at delivery, however, an elective caesarean section appears to offer no additional reduction in transmission. Furthermore, in the general population maternal morbidity following a caesarean section is 5-25 times higher than following a vaginal delivery.

A paper from the European HIV in Obstetrics Group – part of the European Collaborative Study – published in the April edition of AIDS, investigated the occurrence of clinical events in the immediate post partum period following both modes of delivery across 13 European centres. Two separate matched case-control studies (vaginal and elective caesarean deliveries) were conducted among HIV-positive and HIV-negative women delivering between 1992 and 2002.

The investigators reported overall complication rates of 29.2% (119/408) for HIV positive women, 19.4% (79/408) for HIV negative women, 42.7% (135 of 316) for elective caesarean sections and 12.6% (63 of 500) for vaginal deliveries. There were no major complications in either HIV positive or negative women delivering vaginally. However puerperal fever was the only minor complication for which HIV positive women were at higher risk compared to HIV negative women [odds ratio (OR), 4.5; 95% confidence interval (CI), 1.55-13.07, p=0.001)], especially after medio-lateral episiotomy.

In the elective caesarean section group (delivered at 37 to 39 weeks gestation), there were six major complications (five among HIV-positive women, one HIV-negative) (OR, 5.1; 95% CI, 0.58-45) and HIV-positive women had an increased risk of minor complications (OR, 1.51; 95% CI, 1.22-2.41, p=0.001) compared with HIV-negative women, mainly post partum anaemia not requiring blood transfusion.

The authors report a five-fold higher overall prevalence of post partum complications in the elective caesarean section group compared to the vaginal delivery group in both HIV positive and HIV negative women. They explain however that most complications were minor, anaemia and fever, and that serious complications occurred only in women delivering by elective caesarean section. They also reported an increased risk of minor complications following elective caesarean section and a smaller increased risk in complications following vaginal delivery in HIV-positive compared to HIV-negative women.

The authors stressed the importance of HIV positive women’s participation in decisions regarding mode of delivery and that they be informed of potential risks and benefits of each mode of delivery.

Comment

The need for data comparing complications following pre-labour Caesarean section in women undergoing this surgery to reduce the risk of mother to child transmission has long been recognised. This study is therefore welcome and the observation that major complications are more common among HIV-positive women noted. Furthermore, vaginal deliveries result in fewer complications than elective caesarean section in both HIV-positive and HIV-negative women.

However, in the clinic, women elect for either a planned caesarean section or a vaginal delivery, but both groups may deliver by emergency caesarean section with the later more likely to occur in the vaginal delivery group (an 8-10% chance of undergoing emergency caesarean section due to labour complications is reported in this study). The true comparison should therefore be to compare outcomes following the choice of delivery mode using an intent-to-treat rather than an actual treatment analysis.

It is also notable that although minor, vaginal delivery for HIV-positive women is not totally complication free, showing a higher risk for puerperal fever in HIV-positive compared to HIV-negative women requiring a medio-lateral episiotomy. The authors write that their results suggest the need to adopt precautions to reduce the risk of infection specifically for HIV-positive women in this situation and that they may benefit from antibiotic prophylaxis.

Additionally the authors emphasise the importance of a woman’s participation in decisions regarding mode of delivery (including the possibility of an emergency caesarean section in labour after electing to have a vaginal delivery). The BHIVA conference in April 2004 included a presentation of the results of the BHIVA pregnancy audit (which we will report in detail in our next issue). This audit reports a 67% use of elective caesarean section amongst HIV-positive women in the UK including those receiving HAART. Anecdotally, it may be important to add, that although there is much discussion of maternal choice for HIV-positive pregnant women, as a community group with a treatment phoneline, we still receive calls from distressed women being unwillingly led to choose a planned caesarean section in situations where – although still a moot and hotly debated point – this surgical intervention seems to be unwarranted.

Reference:

European HIV in Obstetrics Group. Higher rates of post-partum complications in HIV-infected than in uninfected women irrespective of mode of delivery. AIDS: Volume 18(6) 9 April 2004 pp 933-938