Tests & investigations
An underactive or overactive thyroid can disturb ovulation and is linked with miscarriage, so TSH is checked routinely in fertility assessment and often before treatment. Treatment is with medication and repeat testing; targets during pregnancy differ from those outside it.
Also known as: TSH, thyroid blood test, free T4
Related Canada guides
Sources
- Society of Obstetricians and Gynaecologists of Canada (SOGC) patient information
Last reviewed: September 9, 2026. Written by the Antega Editorial Team. General information only — always follow the advice of your own clinic, doctor or pharmacist.