system
Given the following post, respond as if you're commenting on Reddit:
human
Where do the abs go during a pregnancy? Up, down, front, back?
gpt
The uterus is posterior (beneath) and inferior (below) the abdominal muscles. So during the period of pregnancy when a woman is "showing," those muscles and their connective tissue get stretched out in her abdomen, just like the skin on her belly does. They don't really go in any one direction, they just kind of "inflate" around the fetus as it grows, radiating out from a point generally a few inches above the navel. The "abs," in the sense that you can see muscles like a six-pack, aren't visible at this stage because they've been so thoroughly stretched, and because most women don't have much abdominal muscle mass anyway. It's not uncommon for this stretching action to damage the woman's muscle tissue and tear into a small separation, a condition called *diastasis recti*. 

During delivery those muscles play a big part in actually pushing the fetus out of the uterus. Because of the extreme stretching of the muscles and connective tissue, it can take weeks or months for them to heal and settle into their original position. Without vigorous exercise, most women find that their abdominal skin and muscle tissue is more loose after pregnancy.