Complex sentence: Croft was trained by his father-in-law, Dr. Thomas Denman, a preeminent obstetrician in London at the turn of the nineteenth century, whose textbook on childbirth had been first published in 1788.
Split into simpler sentences: Croft was trained by his father-in-law, Dr. Thomas Denman, a preeminent obstetrician in London at the turn of the nineteenth century. His textbook on childbirth had been first published in 1788.