Crouching in a trench on the front lines in eastern Ukraine, Olena felt the ovulation app on her phone buzz.

“I realized that I really needed to be at home making a baby, not sitting in this trench,” recalled Olena, a combat medic. But that wasn’t an immediate option, and her desire to start a family was as strong as her need to serve.

After about six months of trying — navigating appointments with fertility doctors around her limited leave — “it finally happened,” said Olena, who like other women interviewed for this article requested that only her first name be used for reasons of military protocol. She got pregnant, but continued to serve.

While some people might think fighting a war while pregnant is crazy, Olena said, she sees it “a bit differently.” She added, “War is war, but life goes on.”

Ukraine’s military is finding it hard to recruit young men as the war with Russia grinds on, but women — all volunteers — are a bright spot. The number of women serving has grown more than 20 percent to about 70,000 since Russia’s invasion in 2022.

Those who become pregnant often serve in tough conditions under relentless shelling, living without heat in the winter, or running water and proper toilets.

“It’s terrifying — every single day,” said Nadia, 25, who served as a frontline radio operator until she was eight and half months pregnant. “You wake up wondering if everything is OK, if everyone is still alive,” she said, describing how every morning she would brush plaster off her bed that had fallen from the ceiling after a night of explosions.

Pregnancy, she said, made it even more difficult. The clinic where she would get ultrasounds closed. So did many nearby hospitals.

“You’re constantly thinking about your child’s well-being,” said Nadia, who gave birth to a boy, Yaroslav, in February. “It was nonstop stress every day, combined with constant physical activity.”

While the U.S. Army and many other militaries remove pregnant soldiers from combat zones, Ukrainian women usually serve until their seventh month. And that is in a military that doctors and soldiers say is ill-equipped to support them — from uniforms that don’t fit pregnant women, to a lack of prenatal care and nurseries — amid the costs and challenges of fighting the war.

Despite the hardships, many pregnant soldiers say they understand the military has more pressing priorities and that they are motivated to serve for the future of Ukraine — and their children.

“Our children are the future of this country,” said Olya, 39, a combat medic in eastern Ukraine who gave birth to a girl in May. “We have to protect our children. And we have to liberate the country for their future.”

Once they give birth, women also face wrenching decisions about how long to stay home with their babies, or whether to return to a military that desperately needs them.

Nadia said that after her baby was born, she was allowed 126 days of paid leave if she wanted to return to the front. Otherwise, she could take off three years, unpaid.

“How can I leave him?” she said she wondered, before deciding to take the three years, with the intention of returning to service after that.

Valentyna cut short her maternity leave to return to service.

In the military since 2019, she had worked as an infantry mechanic before the full-scale invasion — an unusual role for a woman.

“I wanted to challenge society by saying that a woman in a complex combat position can perform her duties on an equal footing with a man,” Valentyna said.

She had initially been hesitant to return to service after giving birth in late 2021, worried that a military salary would not support her family. The Russian invasion changed everything, she said.

“Sometimes you have to make difficult decisions to make things better,” she said.

Finding a unit to accept her back wasn’t easy, Valentyna said, partly because of the sexism that experts say is pervasive in the Ukrainian military. Several turned her down, including one whose commander said she should stay home with her baby. She did not get approval until August 2023 — when her son was 18 months old.

Maj. Viktoria Kravchenko has served in Ukraine’s military for over 16 years and is a psychologist who has researched the issue of sexism in the armed forces. She said women who get pregnant can face considerable barriers, like commanders who question their decision to return to the fight after having babies or their fitness to serve.

“It’s no secret that gender bias exists,” Major Kravchenko said as her daughter, chewed a mango slice in her arms at their home in Kyiv last winter.

She added that financial concerns were also a challenge.

In Ukraine, the military covers 126 days of maternity leave. After that, the state provides about $170 a month for the child.

A number of private entities are helping out. One group, Zemliachky, makes and sends maternity uniforms to serving soldiers. Kvitna, a nonprofit, provides free women’s health care from a mobile clinic.

“There was an urgent need,” said Taras Yeftemii, a gynecologist with Kvitna. On one recent rotation, he said, the mobile clinic screened 573 female soldiers. Five were pregnant.

The Ukrainian military did not respond to questions about how many women were pregnant or had given birth in the ranks, or about prenatal care for soldiers.

Dr. Vita Marchenko, 62, has cared for pregnant soldiers at her hospital in Sloviansk, eastern Ukraine. It lacks the staff and equipment for advanced testing but can deliver babies.

“I never thought we would have so many women at war,” Dr. Marchenko said. A female soldier’s pregnancy only differs from a civilian’s in that it provides “more purpose,” Dr. Marchenko said. “They are reminded what they are fighting for.”

Olya, the senior combat medic in eastern Ukraine, said she was surprised to find out she was pregnant last September. “I did not plan to get pregnant. When I went to war, I wanted to fight until victory,” she said.

She initially kept her pregnancy a secret, fearful she might get reassigned.

But when bleeding landed her in the hospital for a week in December, Olya had to inform her commander. Doctors advised her to “take it easy,” according to Olya. She said that was hard to do as she was the only medic in her company and “the guys still need medical help.” Her commander made some adjustments, and Olya stopped going into combat positions.

Still, war was all around her for the duration of her pregnancy. Olya said she talked to her unborn baby, to tell her what was going on around them. And to tell her that she loved her, that they were going to be OK, and that they were doing an important task.

She bristled at the suggestion that some might question her priorities. “I’m ready to assume responsibility that I am near the combat zone with my child. I do everything to protect her,” Olha said. “I have to stay and help here.”

In late May, she gave birth to a baby, Iryna.

While Olya has officially quit the military, she plans to re-enlist in a year or so. “We have very few people left with the necessary level of experience and professionalism,” she said. “And this is a long game, so we are needed.”

Eve Sampson and Nataliia Novosolova contributed reporting.