Ashley Gardner underwent emergency surgery to save the lives of quadruplets she is carrying. One of the two sets of twins in her womb developed twin-to-twin transfusion syndrome, a condition that causes uneven blood flow between twin fetuses as they develop in the womb.

The Utah woman suffers from endometriosis, affecting her ability to get pregnant. Doctors used in-vitro fertilization (IVF) to fertilize her eggs, which were then implanted back into her body. News quickly spread on the Internet after Gardner was found to be carrying four fetuses, following six weeks of IVF treatments.

Doctors diagnosed two of the developing babies as suffering from the transfusion syndrome (TTTS), forcing a trip to California for Ashley and her husband Tyson. There, the couple met with a surgeon who specializes in treating the condition. Upon examination, medical personnel also found the mother-to-be was experiencing a premature opening of her cervix, due to the condition. She was treated with drugs to stave off any contractions that could take place as a result of TTTS.

"I cannot even start to express the amount of fear we have felt! We were so so scared and in the wee hours of the night when we were waiting for surgery the next morning, reading all your amazing comments and prayers for us gave us so much peace! I cannot properly express my gratitude for each and every one of you and your love and concern for us and our sweet babies," Ashley Gardner wrote on a Facebook page after the successful surgery.

Twin-to-twin transfusion syndrome is usually diagnosed with ultrasound imaging. This condition affects between one and three pregnant women out of every 10,000.

Twins sharing a placenta can experience TTTS if their blood vessels do not properly develop. This can force most of the blood to enrich one of the two fetuses, while starving the other of oxygen, along with vital nutrients. Additional blood flow to one twin can result in more urine production, increasing the amount of fluid inside the amniotic sac, leading to discomfort for the mother and occasional early delivery.

Progress of TTTS can often take different courses, making it challenging to treat those diagnosed with the condition. It was first identified in 1875, by German obstetrician Friedrich Schatz.

Actor Michael J. Fox, star of Family Ties and the Back to the Future movies, is one of the best-known celebrities known to have first-hand experience with the condition. His twin daughters suffered from TTTS, forcing doctors to surgically remove the fetuses one month early.

The Gardners are scheduled to deliver their babies - four girls - by cesarean section in December or January.