Saturday, July 14, 2007

Read the Fine Print on Diaphragm HIV Study

Is it true that a diaphragm plus a condom is no better than a condom alone at preventing HIV transmission? That's what a study in the July 13 issue of the Lancet concluded. But there's an interesting detail that makes me wonder just what the study really shows.

Scidev.net reports that "The authors note that the proportion of women using condoms was significantly lower in the diaphragm group than in the control group (54 per cent as opposed to 85 per cent), possibly because of a perceived irrelevance of a second barrier method."

So is it possible a diaphragm alone offers similar protection to a condom? Or better protection than no condom at all? Alas, the study was NOT designed to answer that question but it makes you wonder.

2 comments:

Tiffany Wong said...

I don't think the diaphragm offers similar protection to a condom when it comes to HIV transmission. It's not the same with pregnancy, where the sperm are trying to swim up past the diaphragm to reach the eggs. Rather, HIV travels in the semen and is absorbed by mucous membranes in the vagina, and in the case that a condom breaks, a diaphragm would not prevent this from happening. But you're right, those statistics do make you wonder.

Christine Gorman said...

Hi Tiffany,

There's some research to suggest that maybe there are a lot more HIV receptors in the cervix and not that many in the vagina. If so, (and that's a big if), covering the cervix might (or might not) be a barrier to transmission.

Of course, not to be too crude, a diaphragm would do nothing to protect against anal sex.