What's your advice on how to fix abdomen after pregnancy? (Photos)

Concerns about the appearance of the abdomen are very common among patients consulting with a plastic surgeon. Just like every patient is different…so too is every abdomen. Different problems require different solutions. Your board certified plastic surgeon is uniquely trained to identify the problems as well as the appropriate solution.
The abdomen is commonly addressed via liposuction or abdominoplasty (“tummy – tuck”). Which procedure is best is dependent upon the source of the problem. 
Excess fat deposits underneath the skin can be addressed via liposuction. Liposuction will not address any other issues and may worsen the situation if there are other factors at play (such as skin excess and muscle laxity, see below)
Commonly patients concerns are centered around issues of excess skin as well as fat. A third factor, which is often overlooked by most patients is abdominal wall muscle laxity (typically seen in post partum mommies).  The tummy tuck, also known as abdominoplasty is a surgical procedure designed to eliminate excess skin and fat and tighten the muscles in the abdominal wall to create a smoother and slimmer contour. The tummy tuck is designed to target areas of the abdomen that have not responded to diet and exercise, making it particularly popular among people that have a lot of loose or sagging skin around the abdominal area due to significant weight loss, as well as women with excess skin and stretched abdominal muscles following pregnancy and childbirth. 
Alternatively, EmSculpt is a recently released device which provides muscle toning via high frequency electromagnetic stimulation. It is being employed for abdominal and gluteal toning. Patients will undergo 4-6 treatments over 2-3 weeks (depending upon the area treated). These treatments are relatively low intensity and patients will commonly be engaged with a smart device (phone/tablet) for the duration. Studies (via MRI) have demonstrated radiographic evidence of improvement in diastasis.Based upon your photos, you would likely benefit from EMSculpt. However, this will not address lax skin. The decision should be made based on in-person consultation and exam.
As always, discuss your concerns with a board certified plastic surgeon (ABPS).Donovan Rosas MD
Board Certified by the American Board of Plastic Surgery
Member: American Society for Aesthetic Plastic
Surgery, American Society of Plastic Surgeons
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Thanks for providing the helpful photographs.  Based on your photos you have a moderate amount of subcutaneous fat and skin laxity.  An in-person consultation would help to confirm this, but I think the Emsculpt would be a good option.  It will reverse the diastasis recti by an average of approximately 10%.  You will gain muscle definition and tone, and reduce abdominal fat by approximately 20%.  Like other body treatments, getting rid of fat, gives you a little bit of skin retraction as well, and the increased muscle mass from the Emsculpt should give you some added support.  I would recommend performing Emsculpt first, and then addressing the residual laxity with a skin tightening treatment, whether it is BodyTite, Ultherapy, or other skin tightening technology.