Hi ndpadin,
I think it's ok to proceed with medical, but consult it first with your gynecologist. In our case kasi, my wife was on her 4th month when we received the medical request. We just consulted with her gynecologist kung ok na magpa-chest x-ray. Her gynecologist gave us the go signal, as long as gumamit sya ng lead apron (available naman to at nationwide)
If ever na you decide to proceed with the medical, obtain first a medical certificate from your gynecologist indicating the state of your pregnancy, isusubmit mo din kasi yun dun sa clinic on the day of your medical.
Be ready also after taking the medical exam. In our case kasi, after around 1 and a half months after the medical exam, we received a call from the visa office asking us kung gusto namin magland before my wife's delivery, otherwise, i-defer nila application namin. We opted na magland na lang after delivery. Kaya after the baby's delivery, we immediately informed the visa office and they asked us to submit documents for the new dependent.
If you prefer na dun manganak, follow kikokit's postings in this forum.