Often do parents wonder when the best time frame is for 3D/4D ultrasounds. When it comes to singleton pregnancies and twin pregancies the time window is pretty different. Singles can often (but not always) get great images all the way up to then end of thier gestation. Where as, twins tend to run out of room much quicker, after all there is 8 limbs in there! Twin moms are encouraged to come in for 3D ultrasound as early as 13 weeks to 25 weeks. Around 13 weeks we often can get incredible images of them together in the same image however, as time goes by this may be a little more challenging. Around the 25th week mark the babies should be nice and filled out but not too squished that images are compromised.
Be sure to bear in mind, no matter if your carrying one baby or multiples to stay nice and hydrated a few days prior to your 3D/4D ultrasound. The better hydrated you are the clearer your ultrasound images will appear.