That may be, but it still delivers a message of happiness contained within her and the fact that they used pregnancy in the last scene was in fact a bold choise, but I see it also as how the relationship between slave and master can be as enjoyable as shown here. Probably , another thing they wanted to show was a change in time period. It’s been weeks or even months later and the the resolve of the girl is still as high as it was at the start, even while being pregnant. That’ how I see it anyway. :P