The latest book I've read that included this subject said that the marriage was consummated alright, but Louis didn't know how to ejaculate. Marie-Antoinette's brother Joseph came to investigate the situation and brought about those medical examinations. Then he took Louis off in the garden for a walk and told him what to do. Some months later, Marie became pregnant. This is documented. Joseph wrote home to his mother in absolute astonishment about the situation. His actual words aren't meant for family reading, so I won't repeat them here.

None of my friends can believe a teenage boy didn't know what to do. But this is royalty we are talking about, and I think most people at the time were reluctant to discuss such things with august persons, and Louis was preoccupied with other interests and didn't or couldn't figure it out on his own. This reluctance to discuss intimate subjects also surrounded Queen Victoria and Albert. She was dismayed when the doctor told her to stop having babies, because she liked sex a lot. There were methods of birth control available to her, but no one seems to have been willing to discuss them with her.

Hello all,
Checking medical sites explains that surgery for phimosis can be as much as circumsion or as little as a nick in a spot where the foreskin is tight. The 'nick' seems a likely candidate as his recovery was quick and within a few months the couple were expecting their first child.

After 7 years (sex would have had to wait for MA's system to mature and produce menses) something significant occurred. It doesn't seem at all likely that the young couple suddenly got it right.
Susana