United formed a women's team earlier this year and they are competing in the FA Women's Championship in their inaugural season.
Managed by former England international Casey Stoney, United had scored six after just 35 minutes, with Lauren James netting twice and Sigsworth scoring a hat-trick.
Sigsworth scored twice more after the break while Kirsty Hanson also bagged a brace.
Mollie Green and Katie Zelem also netted one each to give United a dream start to the league campaign.
FT: Aston Villa 0 #MUWomen12— Manchester United Women (@ManUtdWomen) September 9, 2018
United secure their first 3 points of the season with an outstanding victory to kick off the campaign in style. Goals from @jessSigsworth5 (5), @laurenjamess22 (2), @KirstyHanson3 (2), @katiezel, @mollie_green97 and @ellatoone99! #MUWomen pic.twitter.com/AfFPoDI1MZ
United kicked off their competitive campaign with a 1-0 victory over Liverpool in the Continental Tyres Cup in August.
They were beaten 2-0 by Reading Women in their second match of the tournament in front of a record crowd of 4,835 in what was their first home game of the season.
Next up for United is a home clash against Sheffield United Women in the Championship.
They will also take on London Bees Ladies and Durham Women’s FC to round off their September fixture list.