In warm weather, it is especially important to keep food that should be hot hot, and food that should be chilled cold!
Bacteria and parasites can be present in some foods you might be unlucky enough to purchase before they've even reached your front door. Prime candidates are prepared chilled ready meals and side salads like coleslaw which sit on supermarket shelves. Avoid any of these which don't need cooking, and make sure you heat them thoroughly if they do need cooking. Obviously salads like coleslaw are supposed to be eaten straight, so avoid these. Also items which might contain raw or undercooked egg (like posh mayonnaise) and unpasteurised dairy products like soft cheeses should always be avoided during pregnancy.
However, other foods which are quite safe usually, might set off stomach illness which can at least cause you great discomfort and at worst harm you and your baby.
Use your fridge!
Do not leave foods out of the fridge for more than 20 minutes when the air is warmer. If you are going to freeze food you have cooked, make sure you freeze it as soon as it is cool. Even things like cream need to be chilled and not allowed to warm up on the kitchen counter.
The big thaw
If you are using something from the freezer which needs to be defrosted, do this in a microwave with a defrost setting or plan ahead and thaw it in the fridge. Do NOT let it defrost at room temperature.
Raw meat and fish
Store raw meat and fish away from other food in your fridge and when preparing these, use a non-porous surface like a glass or marble chopping board rather than a wooden one. Also make sure you then use another knife for cutting vegetables or fruit which aren't going to be cooked.
Barbecues are popular every summer but these are a real breeding ground for bacteria as salads and meat are often left outside for some time before being cooked or eaten.
Salmonella is a common problem with chicken. Whether it's cooked on a barbecue or in a regular oven, make sure there is not dark pink flesh or blood evident when you're ready to eat it. The juices should run clear when it is cooked. It's a good idea to part-cook the chicken in the oven first, but make sure you do this just before taking it to the barbecue rather than leaving it stand half-cooked for too long and letting in cool down. That will only make the bacteria spread more quickly.
Meats which have been processed, like sausages or burgers, should never be eaten rare (by a pregnant woman or anyone else!) and beef can be a risk from e-coli so make sure it is well cooked.
On a barbecue, make sure you have prepared it hours in advance as this way it will be really hot and the flames won't just burn the outside without cooking the food through.