Fejzo said the number of women who experience hyperemesis is likely much larger than previously thought, because many women are never hospitalized.
That may have been the case with Alison Kenyon, a secretary from Farmington Hills, Minn., who was violently ill through all three pregnancies.
"I was told with the first pregnancy that 'all women go through this' by the RN who answered the phone," she wrote ABCNews.com. "She had no idea what I was going through. In retrospect, I think I should have rehydrated in a hospital but I didn't know any better."
Many nights in her first pregnancy, "I remember wanting to die instead of going to sleep because I knew I would feel absolutely wretched in the morning," she said.
"I was late for work many days and when I wasn't, I had to pull over on the freeway to puke my brains out," she said. "I spent half the work day cradling the public toilet at the office."
After three boys, she said, "Never again. I love my boys but that is pure evil."
Doctors say that most babies of mothers with hyperemesis are born healthy, though in severe cases, women can be at risk for early delivery or smaller babies.
But a new study is underway looking at the health outcomes of those babies.
Dr. Aimee Brecht-Doscher, a Camarillo, Calif., obstetrician, miscarried at 18 weeks after she had hyperemesis, vomiting up to 20 times a day.
"I couldn't eat or drink," she said. "I couldn't take time off from work, so I started taking medications and administering IV fluids to myself every night. When I was on call for labor and delivery, I'd hook myself up to the IV between deliveries. I kept thinking it would resolve, but instead it grew worse."
"Dehydration and malnutrition led to despair. I cried every day," she said. "I believe that [my baby's] death was caused by a specific vitamin deficiency, a vitamin I was not getting in my IV."
Sick with her second pregnancy, she gave birth to a son prematurely at 35 weeks, but today, at 7, he is healthy.
Brecht-Doscher now helps others with Help Her (Hyperemesis Education and Research), an organization dedicated to helping women cope with hyperemesis and finding better treatments.
Help HER was founded in 2000 by Kimber MacGibbon, a former nurse from Portland, Oregon, who also suffered from the condition in two pregnancies.
MacGibbon's son is now 11 and has behavioral, emotional and learning problems that she says may have been caused by her hyperemesis.
Five weeks into her marriage, the overwhelming nausea began. MacGibbon's midwife insisted, her body was "trying to reject the pregnancy."
Horrified and eventually losing 16 pounds off her 135-foot frame, MacGibbon was eventually hospitalized. She was so ill, she dropped out of graduate school.
"They say I looked like something out of a concentration camp," said the 42-year-old, who was eventually treated successfully with Zofran (ondansetron), a drug used to offset nausea in cancer chemotherapy, that has been approved as safe by the Food and Drug Administration.
Today, Help Her supports the research at both University of California and UCLA and is a source of hope for patients like Anuja Batra.
Batra now has 24 weeks to go in her struggling pregnancy, but she is cautiously optimistic that this one won't end up in termination.
"I know that at nine months, it will truly be the end," she said. "I know there is a baby waiting for me and that is my motivation."