Mary Ann was born in Leigh, Worcestershire, England, on December 4, 1773. She married William Phillips on December 3, 1793. Thirteen children were born to this union, two having died young. She lost Willam in 1825. It was likely as a widow in England that Mary Ann received much of her early midwife training.

Mary was a member of the Methodist Church, then joined the United Brethren. In 1840 she was baptized into The Church of Jesus Christ of Latter-day Saints by Wilford Woodruff in Herefordshire. She emigrated to Nauvoo in 1844, in time to see the Prophet Joseph before his martyrdom. She lived on Camp Creek which was fifteen miles from Nauvoo and from where she was driven into Nauvoo by a mob, carried in on a bed of sickness. In 1846 with other church members, Mary and her family were driven out of Nauvoo. They stopped at Winter Quarters, where they lost by fire what little property that had been saved from the mob.

Arriving in the Utah Territory in 1849 and settling temporarily in the Salt Lake Valley, Mary and her family permanently located in Kaysville in 1850 where “she officiated in the capacity of a midwife” and ran her own farm.

It was stated at her funeral by Woodruff that at “the good old age of 82 she gleaned over twenty bushels of wheat and raised thirty bushes of potatoes and dug and carried them into her cellar. She fatted two hogs, and gave a good yoke of oxen the same year to immigrate the poor from England. During the fore part of the winter of this same season she had a fall, dislocating her shoulder and breaking her collar bone, which affected her afterwards in her labor.”

She officiated in the capacity of midwife for forty-five years, and until she was ninety-six years of age waited upon some thirty women annually. Mary never lost a woman under her administration, and never a child until two years before her death.

At the time of her death in 1871,  Mary had 11 children, 35 grandchildren and 31 great-grandchildren. She was said to be the oldest person in the territory.