Beyoncé reveals she had an emergency C-section when she delivered her twins

Music star Beyoncé revealed Monday that she needed an emergency Caesarean section when her twins were born last year.

"I was 218 pounds the day I gave birth to [daughter] Rumi and [son] Sir. I was swollen from toxemia and had been on bed rest for over a month," wrote Beyoncé, 36, in the September issue of Vogue, for which she was granted unprecedented control over her cover shoot and lengthy photo captions. "My health and my babies' health were in danger, so I had an emergency C-section. We spent many weeks in the NICU," the neonatal intensive care unit, at Ronald Reagan UCLA Medical Center in Los Angeles.

Toxemia, also known as preeclampsia, is a common condition in which a woman in late pregnancy develops high blood pressure and protein in the urine. Possible complications including bleeding, premature separation of the placenta from the uterus, rupture of the liver, stroke and, though rare, death. Reality-TV star Kim Kardashian famously suffered from preeclampsia that necessitated the six-weeks-early birth of her and husband Kanye West's daughter North in 2013.

"My husband was a soldier and such a strong support system for me," Beyoncé wrote of rapper and music mogul Jay-Z. "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. Today I have a connection to any parent who has been through such an experience."

She added that, "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. During my recovery, I gave myself self-love and self-care, and I embraced being curvier. I accepted what my body wanted to be."

Explaining that she eschewed "wigs and hair extensions and used little makeup for this shoot" in order for to help people "see and appreciate the beauty in their natural bodies," Beyoncé said, "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."