Final answer:
The correct term for a woman pregnant for the ninth time is Novigravida. The cervix is essential for sperm transportation during fertilization and dilates during childbirth to enable the baby's passage.
Step-by-step explanation:
The term that best describes a woman who is pregnant for the ninth time is Novigravida. A nonagenarian refers to a person who is in their nineties; multipara is a term for a woman who has given birth multiple times, but it does not specify the number of pregnancies; and nulligravida means a woman who has never been pregnant.
Roles of the Cervix in Fertilization and Childbirth
The cervix plays a critical role in both fertilization and childbirth. It produces mucus that helps sperm travel up to the uterus and into the Fallopian tubes to fertilize the egg. During childbirth, the cervix dilates and effaces to allow the baby to pass through the birth canal.