A female infertility patient is found to be hypoestrogenic at the preChapterual clinic visit. She asks the nurse why she has never been able to get pregnant. Which response is best?

A) Circulating estrogen contributes to secondary sex characteristics.
B) Estrogen deficiency prevents the ovum from reaching the uterus and may be a factor in infertility.
C) Hyperestrogen may be preventing the zona pellucida from forming an ovum protective layer.
D) The corona radiata is preventing fertilization of the ovum.

The cilia in the tubes are stimulated by high estrogen levels, which propel the ovum toward the uterus. Without estrogen, the ovum won't reach the uterus. The results of a series of events occurring in the ovary cause an expulsion of the oocyte from the ovarian follicle known as ovulation. The ovarian cycle is driven by multiple important hormones: (1) gonadotropic hormone, (2) follicle stimulating hormone (FSH), and (3) luteinizing hormone (LH).
The cilia in the tubes are stimulated by high (4) estrogen levels, which propel the ovum toward the uterus. The zona pellucida (inner layer) and corona radiata (outer layer) form protective layers around the ovum. If an ovum is not fertilized within 24 hours of ovulation by a sperm, it is usually reabsorbed into a woman's body. A patient who is hypoestrogenic would not have excess circulating estrogen. A patient with low estrogen would not be classified as hyperestrogenic. Without sufficient estrogen, there can be no fertilization of the ovum.