IHTMLDocument2.write() memoryleak - mfc

Question

In MFC CDHtmlDialog, I am updating HTML content using IHTMLDocument2's write function.
My Dialog is a modelless dialog. I am using same dialog object throughout the application.
Everytime I write something to the embedded browser, and look at memory
usage in task manager, the used memory seems to go up by about 750 KB per
IHTMLDocument2::write/close. If I comment out the call to
m_spHtmlDoc->write(pSA); the memory usage is more normal.
I am using below code to update the HTML Content.
IMPLEMENT_DYNCREATE(CEzHtmlChildDlg, CDHtmlDialog)
CEzHtmlChildDlg::CEzHtmlChildDlg(CWnd* pParent /*=NULL*/)
: CDHtmlDialog(CEzHtmlChildDlg::IDD, 0, pParent)
{
CDHtmlDialog::Create(CEzHtmlChildDlg::IDD, pParent);
}
CEzHtmlChildDlg::~CEzHtmlChildDlg()
{
}
void CEzHtmlChildDlg::DoDataExchange(CDataExchange* pDX)
{
CDHtmlDialog::DoDataExchange(pDX);
}
BOOL CEzHtmlChildDlg::OnInitDialog()
{
SetHostFlags(m_dwHostFlags
| DOCHOSTUIFLAG_DIALOG // MSHTML does not enable selection of the text in the form
| DOCHOSTUIFLAG_DISABLE_HELP_MENU // MSHTML does not add the Help menu item to the container's menu.
| DOCHOSTUIFLAG_SCROLL_NO // MSHTML does not have scroll bars.
| DOCHOSTUIFLAG_DISABLE_SCRIPT_INACTIVE // MSHTML does not execute any script until fully activated.
| DOCHOSTUIFLAG_THEME // Specifies that the hosted browser should use themes for pages it displays
// | DOCHOSTUIFLAG_NOTHEME
);
CDHtmlDialog::OnInitDialog();
// disable drop targets
// Don't allow user to drop shortcut onto this window and have the browser
// navigate to show that web site
m_pBrowserApp->put_RegisterAsDropTarget(VARIANT_FALSE);
EnableAutomation();
LPDISPATCH pDisp = GetIDispatch(FALSE);
SetExternalDispatch(pDisp);
return TRUE; // return TRUE unless you set the focus to a control
}
BOOL CEzHtmlChildDlg::PreTranslateMessage(MSG* pMsg)
{
// TODO: Add your specialized code here and/or call the base class
if (pMsg->message == WM_KEYDOWN &&
(pMsg->wParam == VK_ESCAPE || pMsg->wParam == VK_RETURN || pMsg->wParam == VK_F5))
return true;
if (pMsg->message == WM_RBUTTONDOWN || pMsg->message == WM_RBUTTONDBLCLK)
return TRUE;
return CDHtmlDialog::PreTranslateMessage(pMsg);
}
BEGIN_MESSAGE_MAP(CEzHtmlChildDlg, CDHtmlDialog)
END_MESSAGE_MAP()
BEGIN_DHTML_EVENT_MAP(CEzHtmlChildDlg)
END_DHTML_EVENT_MAP()
// CEzHtmlChildDlg message handlers
void CEzHtmlChildDlg::SetHTML(CString strHtml)
{
// Create a safearray to store the HTML text
SAFEARRAY *pSA;
SAFEARRAYBOUND saBound = {1, 0};
pSA = SafeArrayCreate(VT_VARIANT, 1, &saBound);
CComVariant varDummy;
// Copy the HTML into the one and only element
VARIANT *pVar;
CComBSTR bstrHTML = strHtml; // Load the text
varDummy = bstrHTML; // .. into a variant
SafeArrayAccessData(pSA, (void**)&pVar); // Access safearray data
pVar[0] = varDummy; // Set the text data
SafeArrayUnaccessData(pSA); // Release access
// Write the HTML as the document's new text
m_spHtmlDoc->write(pSA); // Overwrite HTML
m_spHtmlDoc->close(); // Update browser
SafeArrayDestroy(pSA); // Finished with the safearray
}
m_spHtmlDoc is a member variable of CDhtmlDialog.
What is the mistake I am doing while writing to document?,