Human Reproduction: FAQ
Frequently Asked Questions


Office Hours

Questions can be directed to the Office Manager of the Fertility Center between 8:00 a.m. to 4:00 p.m. I will try to respond to all questions within 24 hours except on weekends. E-Mail: esther.pherrin@hsc.utah.edu




Topics:

Oxytocin

Libido

Prolactin-Inhibitory Factor

Renal Failure and Hyperprolactinemia

Galactorrhea

Chadwick's Sign

Hegar's sign

Goodell's Sign







Oxytocin

Oxytocin means quick birth. In 1906, Sir Henry Dale discovered uterotonic bioactivity in extracts of the posterior pituitary. Oxytocin is a nonapeptide synthesized in the magnocellular neurons of the supraoptic and paraventricular neurons. Oxytocin prohormone is transported with a carrier protein, neurophysin, along the axons to the neural lobe of the posterior pituitary and membrane-bound vesicles for storage and later release. Progesterone acts to prevent lactogenesis itself, but with progesterone withdrawal after the placenta delivers, lactogenesis begins. Suckling on the breasts by the newborn induces episodic secretion of oxytocin from the maternal neurohypophysis. Oxytocin acts on the myoepithelial cells of the breast ducts to cause milk let-down.



Libido

Males with decreased libido may have low testosterone levels secondary to hyperprolactinemia. Hyperprolactinemia may act to suppress pulsatile GnRH release. Hyperprolactinemia should be considered as a potential cause of hypoandrogenism and subsequent decreased libido.



Prolactin-Inhibitory Factor

Dopamine is the predominant physiologic prolactin inhibitory factor. The axon's response will further release dopamine into the median eminence originate in the perykaryons in the arcuate ventral medial nucleus of the hypothalamus. Other inhibitory factors include gonadotropin-associated peptide (GAP), gamma aminobutyric acid, histidyl-proline, diketopiperazine, pyroglutamic acid, and somatostatin.



Renal Failure and Hyperprolactinemia

Hyperprolactinemia occurs in 73% to 91% of women and 25% to 57% of men with end- stage renal disease. Prolactin metabolism is delayed in renal failure, and there is also increased production. Correction of renal failure with transplantation causes a return of prolactin levels to normal. Hyperprolactinemia may play a role in the hypogonadism found in many patients with chronic renal failure.



Galactorrhea

It appears that approximately 28% of women with galactorrhea and normal menses have elevated prolactin levels. One-third of women with hyperprolactinemia have pituitary adenomas. Two-thirds of women with galactorrhea and amenorrhea have hyperprolactinemia.



Chadwick's Sign

Increased vascularity results in a characteristic violet color of the vagina during pregnancy.



Hegar's sign

Compressibility and softening of the cervical isthmus (the portion of the cervix between the uterus and the vaginal portion of the cervix).


Goodell's Sign

Significant softening of the vaginal portion of the cervix.