This proof of concept study is designed to determine the practicality of using home ovulation tests to enable optimum timing for transfer of frozen embryos in a natural menstrual cycle in comparison to the standard ultrasound and serum monitoring currently conducted by many IVF clinics.

The study will evaluate the ability of home ovulation tests to accurately time Frozen Embryo Transfer (FET) directly compared to standard clinical procedures. In addition, women's likability and stress associated with timing a FET cycle using both methods will be evaluated by collecting qualitative data using standardised questionnaires.

The impact of psychological stress on FET outcome such as implantation rates and viability at first scan will be considered in order to gather information for the design of a larger clinical study and basic financial data will also be collected, in order to pilot a cost-effectiveness evaluation of the two FET timing methods.

A subset of volunteers will collect daily urine samples from day after embryo transfer until confirmation of pregnancy.

Inclusion Criteria:

• Women aged 24 to 45 years of age
• Undergoing no more than 5frozen embryo transfer
• Average cycle length between 26 and 35 days
• Willing to provide written informed consent to participate in the study and comply with all study procedures

Exclusion Criteria:

• More than five IVF frozen embryo cycle
• Undergoing FET following cancer treatment
• Self-reported drug or alcohol dependency
• Self-reported history of depression, anxiety and panic attacks

Biological women only