Glossary of Terms

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B

Basal Body Temperature

Abbreviated BBT. Indirect evidence of ovulation can be obtained with the basal body temperature chart. The temperature can be taken orally with a digital thermometer immediately upon awakening and before any activity. This is recorded on a special graph that enables you to visualize the different temperature shifts. The temperature will drop to its lowest point, 1-2 days prior to ovulation, and then rises and remains elevated until a couple of days before impending menstruation. If the individual is pregnant the temperature will remain elevated. This elevation is not considered a fever because it will never exceed 38ºC (100ºF). This test is unfortunately not very reliable in every woman, and is therefore not used universally. Urine ovulation prediction testing is a better way to document ovulation and to determine prospectively when ovulation will occur. 

Bicornuate Uterus

A congenital abnormality of the uterus that involves a partial lack of fusion of the two parts of the uterus to varying degrees. A single cervix is present. In the majority of cases it does not cause infertility, but recurrent miscarriages have been reported in rare instances, similarly to premature births. If treatment is needed, it is through abdominal surgical repair. 

Blastocyst

An embryo that has undergone multiple cellular divisions with the formation of a cavity within it. A fertilized egg reaches the blastocyst stage usually 4 to 5 days after fertilization. Most embryo transfers at Pacific Fertility Center are done with blastocyst stage embryos.