[Despare]

"Half-Life 2 begins an undisclosed number of years after this war, after the rule of the Combine has been firmly established. There is, however, some evidence from the Half-Life 2: Episode One official website indicating that Half-Life 2 takes place nearly two decades after the Black Mesa incident.[2] Such a time frame is logically consistent with the aging of the series' characters between Half-Life and Half-Life 2. It also explains why there are no children in the game, the Combine having set up a reproductive suppression field a short time after the war, preventing any further births."

The G-Man is really tough to read... the Vortigaunt's obviously (from their reaction to him in HL: E1) don't trust him. Not only that but he WAS the person who gave them the sample which caused the Black Mesa incident. I think it's his "employers" who really need to be worried about though.