The #1 reason pregnant women get rid of their cats is the fear of contracting toxoplasmosis from their cat or the cat's litterbox.
Some doctors are all too hasty with pregnant women to be negative about cats in the household. One of the first things out of their mouths, once they know you have a cat, is the need to get rid of it. Some put the fear of God into these woman about how their babies can be born deformed or with birth defects and make it sound like cats are evil and full of cooties.
You are more likely to contract toxoplasmosis from handling raw meat or unwashed fruits and vegetables then from your cat's litterbox providing you clean it out on a daily basis (which should be done anyway). Those people who clean out litter boxes once a week or once a month run a much larger risk of contracting toxoplasmosis whether they are pregnant or not. Doctors give cats a raw deal (pun intended).
Cats shed the organism for such a short amount of time in their life, chances of exposure to toxoplasmosis are minute.
Cats kept inside are at a much lower risk or ever coming in contact with the organism then outside cats who are allowed to roam and eat mice or other prey.
Don't be one of those people who gets rid of their cat because "I'm pregnant". There are other options, have a family member clean out the box, wear gloves and make sure you wash your hands after cleaning. For information on toxoplasmosis in pregnancy go to Family Doctor.
Learn the facts, become informed, make a wise decision before hauling kitty off to the pound. For information about toxoplasmosis in cats go to Cornell University College of Veterinary Medicine