Inclusion Criteria:

• Females aged 18 and over actively trying to conceive
• At least 2 regular consecutive cycles since last pregnancy/miscarriage/ stopping breastfeeding or contraception
• Willing to disclose their pregnancy status and provide urine samples.
• Willing to give informed consent and comply with the study procedures

Exclusion Criteria:

• Trying to conceive for >6 months (under 35 years) or > 3 months (35 years and over)
• Has a diagnosis of Polycystic Ovary Syndrome (PCOS)
• Taking medication or has known condition which means they should not get pregnant.
• Currently pregnant or breastfeeding
• Using any treatment which may affect the menstrual cycle (e.g. contraceptive pill)
• Using or has previously used infertility medications or hormone replacement medications containing LH or hCG \ (e.g. Pregnyl®)
• Using or undergoing any other medical treatment for fertility such as ovulation drugs, artificial insemination and assisted fertility such as IVF or ICSI
• Peri-or post-menopausal, e.g. experiencing symptoms: irregular menstrual periods, hot flushes, night sweats, sleep disturbances and/or moods swings
• Abnormal liver or kidney function
• Taking antibiotics containing tetracycline.
• Participated in this study within the last 6 months