Reese Witherspoon flashes her cleavage in a challenging low profile bathing suit as she unwinds poolside in Mexico in front of 40th birthday

It's difficult to trust that Reese Witherspoon will be praising her 40th birthday not long from now.

The performing artist looked phenomenal on Wednesday as she flaunted her petite figure while drenching up the sun with a gathering of sweethearts in Cabo San Lucas, Mexico.

Reese stripped down to a dark bathing suit with a diving neck area, blazing her plentiful cleavage and abandoning her thin legs on show.The 39-year-old shielded her porcelain skin from the sun with an extensive straw cap and a couple of shades over her make-up free face.

Reese, who had been brandishing some pink shorts, tied her splendid blonde hair into a whine free braid.