Glossary of Terms

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H

HCG

Human Chorionic Gonadotropin is the major hormone secreted by the placenta. In the early stages of pregnancy, continued survival of the corpus luteum (the follicle that releases the egg) is totally dependent on HCG and, in turn, the survival of the pregnancy is dependent upon hormones secreted by the corpus luteum during the 7th week of pregnancy. Thereafter, the corpus luteum is gradually replaced by placental hormone secretions. Studies have shown that after administering HCG intramuscularly, ovulation occurs 38 to 40 hours afterwards. This is why during an IVF cycle, egg retrieval is scheduled 30 to 40 hours after the HCG shot. Similarly, during simple ovulation induction with Clomiphene or Gonadatropins, HCG is sometimes given to trigger ovulation. HCG is chemically very similar to LH or luteinizing hormone, which signals the ovulation process to begin. Insemination or intercourse is then planned according to the time that HCG was administered.

Hemi-zona Assay

A test that helps determine if sperm are able to attach and penetrate the covering of an egg or zona pellucida.

Human Chorionic Gonadotropin

See HCG.

Hydrosalpinx
Hyperprolactinemia

A condition where there is elevated blood levels of the hormone Prolactin. This hormone is secreted by the pituitary gland. There are several diseases that can result in abnormally high Prolactin levels. Most commonly, this is due to a small and benign Prolactin secreting tumor in the pituitary gland called Prolactinoma. Often this can result from an abnormally slow functioning thyroid gland. The treatment is specific to the cause, but medical management with Bromocriptine (Parlodel) is the first line of therapy.

Hypothalamus

A small portion in the base of the brain that plays a major role in regulating the hormones involved in fertility and the menstrual cycle. (See GnRH).

Hysterosalpingography

An HSG is an x-ray dye test used to visualize the uterus and tubes. It involves the injection of a radio-opaque dye through the cervix and into the uterus and tubes. A series of x-rays is taken and the contour and patency of the uterus and tubes are assessed. The procedure can be somewhat uncomfortable, and may result in some cramping which often lasts for a few hours after the procedure. The likelihood of this occurring can be diminished or lessened by taking Ibuprofen or other pain medications, one hour before the test. In a small percentage of cases an HSG can cause tubal infection. This is more common in women who have one or more blocked tubes. If this is the case, the individual should immediately contact her infertility specialist to be placed on antibiotics for a week.

Hysteroscopy

This is a procedure that involves the introduction of a thin telescope-like instrument through the cervix into the uterine cavity. It enables the direct visualization of the uterine cavity and its lining, thereby providing an opportunity to diagnose abnormalities such as polyps, fibroids or adhesions. It is best performed 2 to 7 days following the end of menstruation. Diagnostic hysteroscopy can be performed with general anesthesia in the doctor's office. The procedure is relatively risk free and is significantly less painful than a hysterosalpingogram. All patients suspected of having surface lesions involving the inner lining of the uterus should have a diagnostic hysteroscopy performed.

Hysterosonogram

As a diagnostic procedure, the hysterosonogram is equal to the hysteroscopy procedure in identifying polyps or fibroids in the uterine cavity. It is performed in the doctor's office or in a hospital radiology department and does not require anesthesia. Ibuprofen is sometimes taken prior to the procedure to decrease the incidence of cramping. A small tube with a tiny balloon is placed into the cervix. Under vaginal ultrasound visualization, a small amount of sterile saline solution is placed into the uterine cavity. If there are any polyps or fibroids in the cavity, they can be easily seen by a doctor, who can then perform a hysteroscopy to remove the lesion(s).