With certain types of lizards like bearded dragons if you gently run your fingers over the belly you can usually feel the eggs
next answer from different answering : you can even tell because they will probably not eat anything or bite you when you pick it up and you will even just get a feeling that ,the lizard is pregnant.
In order to mate captive lizards you need to hibernate them. I think its different for all lizards but heres an example.
Chinese water dragons:
The temperature during the day should be reduced to 75 - 78 F, with a warmer area under an incandescent lightthat reaches 80-84 F. The night time temperature should be reduced to 68 -74 F. Instead of feeding your dragons everyday or every second day, the feeding schedule should be reduced to once per week. This period of lower temperatures and reduced light should last for approximately two months.
http://www.triciaswaterdragon.com/breeding.htm
And of course make sure the animals are well fed.
look for a swollen belly, inflated... you know. also if it starts screaching
Lizards have to conmtact their cloaca's, so they can mate. The male curls his cloaca under the female base of the tail while mating takes place.
Jamaican Traditions and Beliefs - Pregnancy and BirthIf a lizard jumps on a woman, it means she is pregnant or will soon become pregnant.
hemafrodite
You don't need to tell anyone if a dog is pregnant, but if you want to, you can tell the dog's owners.
you can tell that your sea monkey is pregnant when she has a little egg sack on her back but it will take a year before she does get pregnant ( it will take 50 weeks to hatch if pregnant )
I have a bearded dragon and the longest he has gone without food is 3 weeksn i did not want to risk killing him so... ill tell you something great and helpful every lizard has a tail right? right so if every lizard has a tail why do they have a tail? well a lizard has a tail for FOOD STORAGE thats when they store there food incase they will be needing it later which most lizards need there food storage for there 1 week hybernation dureing winter. but if a lizard loses its tail it has to hunt for food more often as it did before because it has no storage available and the tail will re grow but the tail will be shorter it is easy to tell if a lizard is starving because of the following 1 the lizard has a skinny tail 2 the lizard itself looks like he hasnt eaten for a period 3 health issues a lizard can live without food for about 3-4 weeks...
when it is fat and it doesn't move that much all it is going to do is just sit there and make it look like he or she is sick.
Jamaican Traditions and Beliefs - Pregnancy and BirthIf a lizard jumps on a woman, it means she is pregnant or will soon become pregnant.
well, how u can tell its jesus lizard is it has to have a beard.....yup
one has a penis
You Tell Me!
by feeling its belly
sometimes if te baby lizard weighs to much the lizard can sink but yes just make sure its shallow so the lizard feels safe
hemafrodite
If it has a spot on its bottom it's a boy if not a girl
I think by looking at it's scales.
size and color
if the mom is fat !!!!!!