Study of Axillary Skin Temperature as a Marker of Ovulation

Infertility is the most common reason women (aged 20-45yrs)see their GP, affecting 1 in 7 couples. Measuring basal body temperature is a technique that has been used since the 1930's to attempt to predict ovulation. Current NICE guidelines don't recommend the use of BBT charts to predict ovulation, as it has not been established to reliably confirm ovulation. The DuoFertility sensor a CE marked Class la device provides a continuous accurate measure of axilla temperature whilst worn under the arm. The investigators plan to compare the temperature measurements of the DuoFertility sensor with the gold standard transvaginal ultrasound scan obtained during 10 infertile women's menstrual cycles, up to 10 cycles per women. The investigators aim to investigate if continuous axillary skin temperature measurement obtained from the DuoFertility sensor, provides comparable results for identifying the occurrence of ovulation as the gold standard transvaginal ultrasound scan.