Glossary of Terms

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P

Pituitary Gland

A small gland present at the base of the brain. It receives instructions from a specialized area of the brain just above it called the hypothalamus. The pituitary secretes many important hormones, such as FSH, LH, TSH and Prolactin. FSH and LH control the ovaries. TSH controls the thyroid gland and Prolactin controls milk production.

Placenta

The organ that is responsible in the nourishment of the developing embryo. Abnormalities in the placenta can result in abnormal fetal growth, pre-eclampsia and death.

Polycystic Ovarian Syndrome (PCOS)

A genetic condition that results in women with ovulation problems and menstrual irregularity. Can be associated with excess male hormones and insulin resistance. Women with PCOS often require Clomid or other ovulation-inducing medications to stimulate ovulation.

Polyp

Benign growth of the lining of the uterus or the endometrium. It looks like a small solid balloon and can interfere with normal implantation and cause infertility, abnormal bleeding and, theoretically, miscarriages. Polyps can be missed during a hysterosalpingogram, but usually are seen during a hysteroscopy or a mid-cycle endovaginal ultrasound.

Pre-Implantation Genetic Screening (PGS)

An advanced technique to evaluate cells from early human embryos for chromosome copy number. Current techniques use microarrays of human DNA and can determine if there is an abnormal number of chromosomes (for example Down Syndrome) and can determine the sex of the embryo. All 24 unique chromosomes can be tested as well as some other chromosome structural defects.

Preimplantation Genetic Diagnosis (PGD)

An advanced technique that involves checking the cells of a developing embryo for genetic abnormalities and thus helping to prevent serious transmissible genetic diseases.  PGD is indicated when an individual or couple carries a genetic mutation that may put their offspring at risk for a serious genetic disease, for example, Cystic Fibrosis.

Premature Ovarian Failure

POF is the cessation of menstruation due to depletion of ovarian follicles before the age of 40. This disorder can run in families and is occasionally associated with other diseases, such as thyroid dysfunction and/or lupus. Women who suffer from Premature Ovarian Failure may elect to use an egg donor as a means to become pregnant.

Progesterone

A hormone secreted by the ovaries that belongs to the steroid hormone family, like estrogen. Progesterone is secreted by the corpus luteum (see Corpus Luteum), the follicle that produces and releases the egg. The specialized cells of the corpus luteum, that surround the egg, produce high levels of progesterone just prior to ovulation. Progesterone also plays a major role in preparing the endometrium for implantation and supports a pregnancy through the first few weeks of gestation. However, the corpus luteum will stop secreting progesterone if pregnancy does not occur. The progesterone level in the blood will then drop, which induces menses within 24 to 48 hours. This is how a regular menstrual cycle takes place. On the other hand, if pregnancy does occur, the placenta will start secreting the HCG hormone, which will salvage the corpus luteum and cause it to continue secreting progesterone.

Prolactin

A hormone secreted by the pituitary gland. Its major role is to control milk production. Excess secretion can interfere with normal ovulation. This is why prolactin levels are checked in every woman during the infertility evaluation process. Certain women have elevated Prolactin levels due to a small benign tumor in the pituitary gland or the brain. These tumors are often called Prolactinomas. They are usually treated by a medication called Bromocriptine or Parlodel. In rare instances, surgery may be required.

Prometrium

Micronized progesterone in tablet form that is usually used intra-vaginally in the luteal phase of IUI or IVF treatment cycles to augment progesterone being secreted from the ovary.