During the pregnancy, the body goes through many changes. The center of balance changes as your tummy grows, and this can lead to pain in the muscles and joints. Especially endangered are the lower back and hips due to the spread of the abdominal muscles. After delivery, these muscles are relaxed, and therefore your stomach has only slightly decreased. It takes time, proper nutrition and easy exercise to restore the stomach to an earlier state. Many women say girdles for new mommy were very helpful (supposedly they help to “get back to their place”). 
The girdles support the stomach, reduce back pain, and stabilize the pelvic muscles and help stabilize the spine. They support the stomach muscles and protect the internal organs. Of course, it’s also important to choose the right girdles. While some mothers claim that they have managed to get back in shape with a strong and thick corset, others say that it only worsened the condition and diminished muscles. It is very important what kind of girdles you use. The best advice is to wear a comfortable girdles, which is not too harsh and that does not stretch (or posttraumatic deep panties), and only a few hours during the day, and to practice walking with a healthy diet back at the earliest 1.5 months after delivery. Of course, you should consult your doctor about exercise and nutrition.
There are various girdles, various models.

 For more information about this kind of girdles, read source.

These belts are ideal after birth. make it easy for your stomach to return to normal. The material from which they were made are of high quality, and they are very comfortable to carry. You will not even feel wearing them. You can carry them wherever you go, to some kind of event, training, stroll …
One of the most obvious benefits to wearing a corset is that it helps move everything back into place. In other words, it helps you get back to your pre-pregnancy shape.

Girdles can be worn the day after you give birth and for as long as you want, provided your doctor says it’s okay.Most moms will wear them for six to eight weeks, but you can continue wearing it if you need extra support or want to improve your posture.