Wichita ? Sondra Headrick, the expectant mother of sextuplets, continued to fight pre-labor contractions Wednesday that were hitting her every seven to 20 minutes, prompting worries that she might deliver her sextuplets more prematurely than she had hoped.

Her doctor brought the contractions to a halt with medications late Tuesday, after two days of trying. Contractions, if they come frequently and can’t be brought under control, could force an early delivery that Sondra wants to avoid because of the danger of birth defects associated with premature birth.

Her doctor is hopeful he can continue to keep contractions under control and buy some more time.

“But things are getting nebulous now,” he said Tuesday.

Also, Sondra’s suffering has increased dramatically since Monday morning.

Her unborn sextuplets are “thriving like gangbusters” at 27 weeks of the pregnancy, said her doctor, Van Bohman. Sondra is using drugs, determination and willpower to extend the pregnancy, he said.

“The pain and discomfort she’s enduring now is like what you see in the last mile of a marathon,” said Bohman, a high-risk pregnancy specialist.

“We’re experiencing the latter parts of this pregnancy now. The babies could be delivered as early as today; it could be a month from now, too, but we’re teetering right on the line today.”

Sondra wants to hold the line. In a brief interview in her room Tuesday, she said she wants to hold out longer “because the babies might have birth defects if born now.”

She knows from her own research that babies born at 31 weeks of the pregnancy have an excellent chance of avoiding birth defects associated with prematurity. She’s been hoping to go another three to four weeks.

Bohman, when told of this later, said that Sondra’s concern is understandable but that “it’s not necessarily true,” that her babies would have defects if born now.

“The fact is, she’s done such a great job of managing this pregnancy that there’s a pretty doggone good chance the babies are going to be normal if born now,” he said. “We’re dealing here with a determined mother who’s given these kids a real chance.”

The babies all now weigh between two and a quarter and two and a half pounds.

If born now, Bohman said, the chances of each baby’s survival would be perhaps 80 percent to 90 percent. The chances of long-term disability for each of her six babies would be perhaps 10 percent.

Sondra is breathing now with either an oxygen tube or mask on her face all the time. Bohman ordered the oxygen because her womb has expanded so much that “it’s literally cramping her lungs.”