Please read the following table in HTML format from a webpage and then answer the question in detail according to the table. Each table cell is defined by a <td> and a </td> tag. Each table row starts with a <tr> and ends with a </tr> tag. 'rowspan=m' and 'colspan=n' represents a cell spaning over 'm' rows and 'n' columns.

Webpage title:
Gestational diabetes
Table title:
Screening
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Condition </th><th colspan=1 rowspan=1 > 2-hour glucose </th><th colspan=1 rowspan=1 > Fasting glucose </th><th colspan=2 rowspan=1 > HbA1c </th></tr>
<tr> <td colspan=1 rowspan=1 > Unit </td><td colspan=1 rowspan=1 > mmol/l(mg/dl) </td><td colspan=1 rowspan=1 > mmol/l(mg/dl) </td><td colspan=1 rowspan=1 > mmol/mol </td><td colspan=1 rowspan=1 > DCCT % </td></tr>
<tr> <td colspan=1 rowspan=1 > Normal </td><td colspan=1 rowspan=1 > <7.8 (<140) </td><td colspan=1 rowspan=1 > <6.1 (<110) </td><td colspan=1 rowspan=1 > <42 </td><td colspan=1 rowspan=1 > <6.0 </td></tr>
<tr> <td colspan=1 rowspan=1 > Impaired fasting glycaemia </td><td colspan=1 rowspan=1 > <7.8 (<140) </td><td colspan=1 rowspan=1 > ≥6.1(≥110) & <7.0(<126) </td><td colspan=1 rowspan=1 > 42-46 </td><td colspan=1 rowspan=1 > 6.0–6.4 </td></tr>
<tr> <td colspan=1 rowspan=1 > Impaired glucose tolerance </td><td colspan=1 rowspan=1 > ≥7.8 (≥140) </td><td class="highlighted"  colspan=1 rowspan=1 > <7.0 (<126) </td><td colspan=1 rowspan=1 > 42-46 </td><td colspan=1 rowspan=1 > 6.0–6.4 </td></tr>
<tr> <td colspan=1 rowspan=1 > Diabetes mellitus </td><td class="highlighted"  colspan=1 rowspan=1 > ≥11.1 (≥200) </td><td colspan=1 rowspan=1 > ≥7.0 (≥126) </td><td colspan=1 rowspan=1 > ≥48 </td><td colspan=1 rowspan=1 > ≥6.5 </td></tr>
</table>
Question:
How is the diagnosis of GDM determined? 
Answer:
When the plasma glucose level is found to be higher than 126 mg/dl (7.0 mmol/l) after fasting, or over 200 mg/dl (11.1 mmol/l) on any occasion and if this is confirmed on a subsequent day, the diagnosis of GDM is made and no further testing is required.