A 36-year-old woman conceived naturally with twins after undergoing successful in vitro fertilization treatment. In the representational image, a mother feeds her triplets as they attend the children's Festival Of Twins, in Kiev, Aug. 11, 2018. GettyImages/ SERGEI SUPINSKY

A 36-year-old woman who could not conceive since she got married eight years ago, delivered triplets after conceiving one child through in-vitro fertilization (IVF) and a pair of non-identical twins naturally in the same week. Doctors termed the probability of that happening “almost impossible.”

Beata Bienias from Wiltshire county in southwest United Kingdom — who had lost all hopes of becoming a mother naturally, given her health troubles— went for an IVF embryo transfer May 2, without realizing the fact she had already become pregnant the same week, and that too, with twins. She delivered three babies Dec. 13 after eight and a half months of pregnancy.

“It was the biggest miracle. I never thought something this incredible could happen to me. I spent many days thinking that maybe I was the person who would never have a baby,” the ecstatic mother told Mail Online. “I never, ever thought there would be three in there. I still can't quite believe it when I look at the three of them. I'm so happy.”

Bienias was trying to conceive ever since she married her husband Pawel, 40, but she could not succeed because she was suffering from obesity, and her extra weight caused her polycystic ovaries. She visited a fertility clinic after failing to conceive naturally, and was advised to lose some weight to advance the chances of getting pregnant. At that time, she weighed about 240 pounds. In the summer of 2017, she joined a weight loss plan and reduced about 70 pounds in six months, making herself eligible for an IVF embryo transfer.

After the IVF procedure was done successfully, the couple went on a holiday to celebrate. After returning from the trip, they went for the first scan at a fertility clinic and discovered it was not one but three fetuses in Bienias’s womb.

“We were told the two twins were conceived naturally. I couldn't believe it - after so many years of trying and getting nothing, and then having IVF and conceiving naturally,” the mother expressed her feelings.

Fertility expert Emma Cannon, with 25 years of experience, called the incident rarest of rare.

“In my 25 years as a fertility specialist, I have only come across one or two scenarios in which women have fallen pregnant whilst undergoing IVF treatment,” Cannon told Mail Online. “I have never encountered anyone who has conceived naturally before, or around the time of, embryo transfer, and then gone on to become pregnant via the IVF cycle as well.”

Bienias and her husband Pawel are now parents to 4-week-old Amelia and twins Matylda and Borys. All the babies and the mother were healthy and doing well.