A positive urine beta human chorionic gonadotropin test (βhCG) is sufficiently sensitive to confirm a pregnancy[6].

Ultrasound: Ultrasound provides the most accurate measurement of gestational age (GA) but is not a routine requirement unless the patient is uncertain of their last menstrual period (or there are symptoms and risk factors for ectopic pregnancy as explained later). It is recommended to choose an ultrasound clinic whose staff are capable of offering non-judgmental sonography[6].

Medical history: If the patient is certain of their last menstrual period and if they were having regular periods without recent use of hormonal contraception, GA estimate that is based on their date would correlate closely with the results from ultrasound[6].

Gynaecological examination: In the first trimester, determination of GA with bimanual exam has been shown to be accurate within 2 weeks of GA determined by ultrasound; however, accuracy varies with the prescriber’s experience and with the amount of adipose tissue and the presence of fibroids[6].

βhCG test: βhCG level rises linearly during the first 6 weeks of pregnancy but the high variability thereafter limits the utility of βhCG for dating[6].