Prolactin explained

Made by the pituitary gland at the base of the brain. Its main role is milk production after birth, but it is present at low levels always, and a raised level outside pregnancy interferes with ovulation. Stress, several common medications and the blood draw itself can all raise it, which is why a mildly high result is usually repeated before anything is concluded. A treatable cause of absent periods: Raised prolactin is one of the standard tests when periods have stopped or become irregular without an obvious explanation, and when conceiving is difficult.

Fasting: Not required. Best time: Morning, and not immediately after waking. Avoid beforehand: Exercise beforehand; Breast stimulation or examination beforehand. Come rested if you can. Stress and a poor night's sleep both raise it, and a raised result means a repeat visit.

Commonly: stress, including the blood draw itself; exercise and sleep in the hours before; pregnancy and breastfeeding; an underactive thyroid; some antidepressants and anti-sickness medicines. A single result is not a diagnosis. Values are read against the laboratory's own reference range and alongside your history, your symptoms and the rest of the panel — which is why every package includes a doctor to go through them with you.

At Smart Care Polyclinic, 29 Doha Centre, Al Maktoum Rd, Deira, Dubai. It is included in the Smart Extra Health, or it can be ordered on its own. Walk in during opening hours or call +971 (0)4 379 3562.