The singing superstar reveals she almost died giving birth to daughter Rumi and son Sir months ago.
The 36-year-old has always been fiercely protective of her private life, but in a remarkably candid major interview — her first for four years — she opens up about the medical emergency.
She tells how she suffered pregnancy-induced hypertension which saw her body swell to 15st 5lb, and talks about the last-minute Caesarean section which possibly saved her life and her babies.
She also alludes to overcoming her spat with rapper husband Jay Z, 48, which prompted rumours he had been unfaithful, and says she has emerged feeling “sexier”, “more beautiful” and “more powerful” than ever.
In September’s issue of Vogue, Beyonce reveals, “I was 218lb the day I gave birth to Rumi and Sir.
“I was swollen from toxemia and had been on bed rest for over a month. My health and my babies’ health were in danger, so I had an emergency C-section.
“We spent many weeks in the NICU (Neonatal Intensive Care Unit). My husband was a soldier and such a strong support system for me.
“I am proud to have been a witness to his strength and evolution as a man, a best friend, and a father. I was in survival mode and did not grasp it all until months later.
“After the C-section, my core felt different. It had been major surgery.
“Some of your organs are shifted temporarily, and in rare cases, removed temporarily during delivery.
“I am not sure everyone understands that. I needed time to heal, to recover.”
Just over a year on, the American superstar, who also has a six-year-old daughter, Blue Ivy, with Jay, is still embracing the way pregnancy has changed her body.
Despite recent false rumours that she was expecting again, Beyonce insists she is not worried about shedding her remaining baby weight.
She says, “After the birth of my first child, I believed in the things society said about how my body should look. I put pressure on myself to lose all the baby weight in three months, and scheduled a small tour to assure I would do it. Looking back, that was crazy.”
Now, she is happy to accept her curves and imperfections — even what she calls her mommy pouch.
She says, “During my recovery, I gave myself self-love and self-care, and I embraced being curvier. I accepted what my body wanted to be.
“After six months I started preparing for Coachella. I became vegan temporarily, gave up coffee, alcohol and fruit drinks. But I was patient with myself and enjoyed my fuller curves. My kids and husband did too.
“To this day my arms, shoulders, breasts and thighs are fuller. I have a little mommy pouch, and I’m in no rush to get rid of it. I think it’s real.
“Whenever I’m ready to get a six-pack, I will go into beast zone and work my ass off until I have it.”
The twins’ traumatic birth was in June 2017. Ten months later Beyonce was back on stage performing two concerts at the annual Coachella Music Festival in California.