what size outfits ?

We are having b/g twins in 2 weeks ! Our daughter was 7.2lbs when she was born, and she swam in newborn clothing until she was about a week, did you buy preemie for your twins , and did you use it?? We got each twin a preemie sleeper , and preemie outfit. I have a scheduled c-section at 38 weeks , last sonogram was week 35 both babies were about 4.3lbs ! Thanks for any input !