The 48-year-old Sherpa successfully reached the 8,848-metre high peak on Wednesday morning, breaking the previous record of 21 climbs jointly held by fellow Nepalis Appa Sherpa and Phurba Tashi Sherpa.
Ms Lhakpa, 44, reached the peak for a ninth time via the northern Tibetan route, her brother Mr Mingma Gelu Sherpa said.
A boom in climbers has made mountaineering a lucrative business since Sir Edmund Hillary and sherpa Tenzing Norgay made the first ascent in 1953.
Ethnic sherpas, renowned for their endurance and experience at high altitudes, serve as guides for many foreign mountaineers attempting to climb the highest Himalayan peaks.
A guide for more than two decades, he broke the previous record of 21 summits that he shared with two other Sherpas.More news: Hart, Wilshere Dropped As England Name 23-Man World Cup Squad
Alpenglow Expeditions said in a statement: "Multiple teams using the same device have experienced similar oxygen system failures".
Mr Kami Rita first reached the top of Everest in 1994 when working for a commercial expedition.
Lhakpa stood at the top of Everest early on Wednesday too. In case there was any doubt about her physical strength, she climbed Everest once when she was two months pregnant, and once only 8 months after having a baby.
Sherpa is a single mom to three kids and lives in Hartford, Connecticut where she works as a dishwasher at the local Whole Foods.
Kami is a professionally trained Sherpa while Lhakpa is a housewife and avid climber.More news: Dee Gordon ready to play second base for Mariners with Cano out
The daughter of a yak herder, Ms Lhakpa worked as a porter and kitchen hand on trekking and mountaineering expeditions, before becoming a climber herself.
"It has obviously excited me with the feeling that I am going to set a new world record".
Foreigners must pay $11,000 for a permit but cut-price climbing outfits skimping on basic safety requirements have flourished in recent years, luring amateurs to the challenge.
Climbing from the Chinese side of the mountain, Sherpa's trip the summit extended her own women's record.
Sherpas are famous for guiding mountaineering expedition and majority come from Solukhumbu district, home to the Everest, or nearby mountainous districts.More news: Facebook says it took down 2 million terrorism posts in 2018