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More than 50 foreign surrogate babies have been born in Ukraine bomb shelters since the start of the war.
Surrogacy company BioTexCom says 27 have been delivered to foreign parents, while another 25 are being cared for by nannies in makeshift shelters.
The company is working with volunteer medics, Warriors Without Borders, to safely deliver the children to their parents across the Polish border and is urging patients to "keep calm and don’t panic".
It posted a video of the babies being cared for in the shelter.
"The war did not stop work at BioTexCom," the company said.
"Since the beginning of the full-scale war, 52 babies were born and 27 of them have already safely got home to their parents.
"All newborns are in a safe place and under the 24-hour care of professional nurses and doctors.
"It is rather impossible to be ready for a war, however, BioTexCom employees have adjusted. We did everything to make the underground accommodation in a shelter a comfortable place.
"We have all needed victuals, water, hygiene products, cribs, strollers, as well as all facilities for keeping babies healthy. Babies continue to be born and BioTexCom continues to work hard no matter what."
Parents around the world are anxious to be united with their newborns.
"We didn't think about material values," one of BioTexCom's nannies said.
"We quickly took children, took what we prepared in advance, and went down to the underground room, which was prepared by our leaders."
Ukraine is one of the few countries in the world to allow mothers to carry babies for foreigners as a commercial practice.
It is estimated up to 3,000 children are born every year in Ukraine for clients outside the country, including in China, the United States and the EU.
Ylva Johansson, the EU's commissioner for internal affairs, expressed concern for children from surrogate mothers who were later put in orphanages and has been calling for the evacuation of such institutions.
She told members of the European parliament that parents in European Union member states and the United States had trouble getting their babies out of Ukraine even before the invasion.
"During the pandemic many of those newborn babies have not been picked up, so they have been stuck and are now being taken care of in orphanages," she said.
"Surrogate mothers that gave birth to babies right now, these babies cannot be picked up either and they are a bit in limbo.
"From my point of view, there is a huge need of evacuations for these children."
Warriors Without Borders has been given an ambulance by Sweden and is gradually moving the babies to safety across the border.
"Today one more desired baby was successfully driven, with the help of a volunteer organisation, to the border of Poland, where his parents are waiting to pick up their child," BioTexCom said.
"Our solicitous intended parents enlisted the support of a volunteer organisation, which gave a lending hand to BioTexCom, providing a safe and comfortable transfer of the baby on an entirely voluntary basis."
BioTexCom currently has about 600 pregnant surrogate mothers and at least one child is born every day.
Legal teams around the world are working to help parents gain access to their children because the babies need to be documented in the birth register and be issued with a passport so that they can be taken out of the country and their parents recognised as legal guardians.