Pregnant women may be exposed to paint through different circumstances that include household use, recreational use, or occupational use. There are basically three categories of paint which you could be exposed to: latex, oil, and enamel. The degree of toxicity during pregnancy is challenging to predict because there are currently no methods of measuring actual exposure. The likelihood of paint toxicity depends on the chemicals and solvents found in the paint along with the amount of exposure.
There are currently no scientific studies that document the effects of household painting on pregnancy and the developing baby. From what we assume, household painting involves very low levels of exposure to toxic chemicals. However, it is recommended still to minimize or avoid painting altogether, if possible.
Lead based paint was often used prior to the 1970s, so you should avoid getting involved with removing old paint in an older house because of the risk of lead exposure. The FDA has indicated that exposure to lead paint increases the likelihood of lead poisoning and mental retardation, not just during your pregnancy, but during childhood as well. Scraping and sanding of old paint puts higher concentrations of solvents and chemicals in the air to be inhaled, and thus should be avoided. For this part, you should have someone else scrape and sand and remove yourself from the location until the project is complete.
If you absolutely must paint the nursery, there are some guidelines you can follow to decrease the likelihood of paint exposure. First protect your skin by wearing protective clothing that includes long pants, long-sleeved shirts and gloves. Second, be certain that the room and house are well ventilated; open the windows and turn on fans. Next, limit the time you spend on the project; take breaks and move into the fresh air frequently. Finally, keep your food and drinks away from the area so that solvents and chemicals will not accidentally be consumed.