Q. I’ve just found out I’m pregnant and I have a holiday booked. Is it safe for me to fly?

A. It's usually safe to fly while you're pregnant and it shouldn't harm your baby if pregnancy is straightforward.

Most airlines will not let you fly after week 37 of pregnancy, or week 32 if you're pregnant with twins or more babies.

If you're planning on travelling by plane, you should discuss it with your midwife or GP first if you are beyond 28 weeks through your pregnancy.

Some women try to avoid travelling in the first 12-15 weeks of pregnancy, because exhaustion and nausea tend to be worse at this early stage.

Check with your airline and insurance company that they will allow you to travel while pregnant. If you haven’t already booked, check with them first before you commit to paying any money. After you get to 28 weeks, most airlines require a letter from your midwife or GP confirming: that you're in good health; that you have a normal pregnancy; the expected date of delivery; Be aware that your GP may charge you for the letter.

Some airlines may require medical clearance if: your delivery date is less than 4 weeks after your departure date complications are expected in your delivery

This may involve your GP or midwife filling in a form, or an assessment by the airline staff.

Check with your airline, as the restrictions can vary.

Flying for longer than 4 hours (long-haul travel) increases your risk of getting blood clots (thrombosis). See below for some tips to help you with this.

Q. I’m flying a long way soon, how can I avoid getting blood clots or thrombosis?

A. Flying anywhere for longer than four hours increases your risk of getting blood clots. However, it is rare in otherwise healthy people.

Here are some tips you can use:

Wearing correctly-fitted compression stockings will reduce your risk of blood clots and fluid being retained in your legs (oedema). You can buy these over the counter in a pharmacy.

The following things can also reduce your risk of blood clots: wear loose, comfortable clothes; do calf exercises at least every half hour – raise your heels, keeping your toes on the floor, then bring them down 10 times. Then raise and lower your toes 10 times; walk around whenever you can; drink plenty of water and do not drink alcohol or take sleeping pills.

Wearing compression stockings or flight socks during journeys of three or four hours or more can help prevent DVT if you're at an increased risk.

The stockings or socks are usually knee length; compression stockings can also be thigh high.

They work by putting gentle pressure on your leg and ankle to help blood flow.

Compression stockings and flight socks come in different sizes with different levels of compression. Class 1 stockings have the lowest compression (with a pressure of 14-17 mmHg at the ankle) and are generally sufficient to prevent DVT.

It's important that compression stockings are worn correctly. Ill-fitting stockings could further increase the risk of DVT.

Get advice on size and proper fitting from a pharmacist.