PROCAARE: CLINICAL SCIENCE--PERINATAL INFECTION

["Gerard J. Nau (Jerry)" <gnau@usa.healthnet.org>]

KEYWORDS:  TRANSMISSION/ PERINATAL/ MATERNAL/ OBSTETRICS/ RUPTURE OF 
MEMBRANES/ CLEANSING/ MALAWI
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Reference:  Biggar, R.J., Miotti, P.G., Taha, T.E., Mtimavalye, L., 
Broadhead, R., Justesen, A., Yellin, F., Liomba, G., Miley, W., Waters, 
D., Chiphangwi, J.D., Goedert, J.J.  (1996)  Perinatal intervention trial 
in Africa: effect of a birth canal cleansing intervention to prevent HIV 
transmission.  Lancet  347:1647-1650.

This study assessed the impact of a simple intervention on the perinatal 
transmission of HIV-1 in Malawi.  Nearly 7000 deliveries were included in 
the study; 30% of the enrolled women were HIV seropositive and 3637 
underwent vaginal cleansing: vaginal cleansing with 0.25% chlorhexidine 
gluconate every four hours until delivery as well as washing the infant 
after delivery.  Women were excluded for complicated deliveres, those who 
were in the second stage of labor, or those who could not fully understand.  
Importantly, 70% of women presented after they had rupture of membranes 
and frequently delivered after only one or two washes.

Subgroup analysis of the results showed that perinatal transmission was 
reduced only in those women who had rupture of membranes greater than 4 
hours (25.0% in the intervention group versus 39.4% in the control 
group).  However, there appeared to be no effect on transmission if 
cleansing was initiated before or after rupture.  

While the authors cautiously point out that multiple subgroup analyses 
can sometimes lead to erroneous findings, the results are intriguing 
given other findings that show prolonged rupture of membranes to be a 
significant risk factor for transmission (see ProCAARE archive.960618).  
The authors also mention that the intervention may  have a beneficial 
effect on Group B streptococcal transmission.  A study designed 
specifically to compare vaginal cleansing in women with and without 
prolonged rupture may demonstrate the benefits of this intervention more 
convincingly.