Tanning while pregnant..

I'm 18 weeks and my gender reveal is coming up in a month.. I'm white as a ghost and I'm not into fake tanning lotions and sprays. AND WOULD NEVER STEP FOOT NEAR A TANNING BED. I'm talking about tanning and laying out in the sun. I know I can tan that way while pregnant, but is it ok to lay on my tummy to tan my back? I feel like I'll crush the baby! I already don't sleep on my tummy for that reason when that's usually the only what I could sleep. 
UPDATE; since someone who commented doesn't know how to read, I AM NOT TALKING ABOUT FAKE TANNING OR TANNING BEDS, I have never and will never do that shit it's dangerous as fuck without being pregnant, why would I do it while pregnant? I'm talking about LAYING OUT IN THE SUN. Nowhere does it say anything about wanting to go in a tanning bed... I specifically stated I hate anything to do with a FAKE TAN. I'm talking about laying out in the sun.
ANOTHER UPDATE; I am very petite and rage from size small/xsmall, with a bump already so it is uncomfortable to lay on my tummy at times