As your pregnancy progresses, or if you spend a lot of time sitting (e.g. desk job), a very common body part that gets tight is the front of your hips: your hip flexors. A few muscles contribute to this, one of which is the quadriceps (quads), which are the muscles running along the front of your thighs. And so one way to relieve tightness in the hip flexors is to stretch the quad muscles:
Stand, and hold onto a stable object for balance
Place one foot on a chair or table behind you, as demonstrated in the photo
Your standing leg should be at, or slight in front of, your bent leg
This is the most important part: SQUEEZE YOUR BUTT -- this tucks your tailbone under
You should now feel the stretch in the front of the thigh (quads) of the bent leg. Hold for 30 to 60 seconds, then release; don’t hold this static stretch for longer than 1 minute.
Switch legs and repeat.
If you feel the stretch in your bent knee, try adjusting/lowering the height of your chair or table. And contrary to popular belief, your heel does NOT need to touch your gluteus in order for this stretch to be effective. It’s a great little stretch at the end of your workout, and/or throughout your work day -- add it to your daily regimen!