Your expanding boobs can be one of the first signs of pregnancy. As they expand you need to make sure you are regularly fitted for a good maternity bra so that your breasts are properly supported over the next nine months.

It is important that you take care of your breasts during pregnancy. They will get bigger and heavier and, as your breasts have only ligaments and no muscles, they could be stretched if they are not properly supported.

Most mums-to-be experience an expanding bust, and sometimes sore breasts, well before a growing tummy -- at around eight to 10 weeks -- and many outgrow their ordinary bras early in pregnancy. As soon as your normal bra starts to feel uncomfortable you should start wearing a maternity bra. Wearing a well-designed maternity bra is the best way to support your breasts.

When you are shopping for a maternity bra look for the following:

Support: look for wide straps, sides, under-bust band and a deep centre at the front. Firm elastic straps eliminate bounce and give you extra support.

Coverage: you need as much fabric as possible over the breast area; this will be more comfortable for you as your breasts become more sensitive.

Comfort: look for bras that are mainly cotton; many women find that they get hot while pregnant; cotton lets your skin breathe so you are less likely to sweat.

What size should I buy?

Ideally you should be fitted by a trained bra fitter as they will be able to take your body shape, bust shape, brand quirks and budget into consideration, but if you’re short of time, measuring yourself is easy:

1. Find your band size. Place a tape measure around your rib cage, placing it just under your bust at the front and making sure the tape measure is flat and straight across your back. Pull the tape nice and snug and measure in inches. Take this number and add 4inches. If it’s an odd number, round up or down to the nearest even number and add 4 inches. This is now your band size. (e.g. you measure 29.7in, round up to 30, add 4 and your band size is 34)

2. Find your cup size. Wearing your normal bra, measure across the fullest part of your breasts. Make sure the tape measure is fairly loose and measure in inches.

3. Find your band size in the column on the left in the table below, then follow the row across until you find your cup measurement. This will be your cup size. For example, if your band size is 32, and your cup measurement 35 inches you will be a 32D.

Top tips:

* When buying a maternity bra, you should make sure that you give yourself room to grow so make sure that it fits snugly on the tightest hook.
* When buying a nursing bra you should be able to fit your hand inside the cup so that you will have enough space for breast pads.