Dee Caffari is sailing against the prevailing winds and currents

Dee Caffari, from Gosport, Hants, and her yacht Aviva will be the only "party guests" at Monday's event.

She has a box with cards and presents to open, and she hopes to speak to her parents in the UK over the weekend.

The former PE teacher set off in November to become the first woman to make the 26,000-mile trip.

She will spend her birthday surrounded by thousands of miles of open water in every direction.

At my lowest points, it is the messages of support that have flooded in from all over the world that really help keep me going Dee Caffari

The yachtswoman is currently about 2,500 miles from New Zealand, 1,850 miles from Chile and 9,800 miles from home in the UK and the nearest landmass to her is Antarctica.

She said she has received thousands of emails through her website from almost 40 countries across the world, including Zimbabwe, Iceland, China, Sri Lanka, Croatia and India.

"At my lowest points, it is the messages of support that have flooded in from all over the world that really help keep me going," she said.

The remainder of the expected 170-day journey could bring 40ft waves, extremes of temperature and severe lack of sleep for Miss Caffari, with sometimes as little as one hour in a 48 hour period.

The current world record for a non-stop single-handed circumnavigation of the globe against the prevailing winds and currents is 122 days, 14 hours, three minutes and 49 seconds, and is held by Frenchman Jean Luc Van Den Heede.