Intermediate
Technical
In the Industry Vocabulary Test
Follicular Phase
The first half of the menstrual cycle, from menstruation onset to ovulation.
Full Definition
The follicular phase begins with menstruation and extends until the luteinizing hormone surge triggers ovulation, typically lasting 12-14 days. During this phase, FSH stimulates follicle development while estradiol levels gradually rise. Hormone testing during the early follicular phase (days 3-5) provides baseline measurements for reproductive hormones and is crucial for fertility assessments and diagnosing conditions like PCOS or premature ovarian failure.
Usage
Usage note: Always lowercase 'phase' unless beginning a sentence.
In Context
- "FSH and LH should be measured during the early follicular phase for baseline assessment." — Fertility testing protocol
- "The follicular phase may be prolonged in women with PCOS." — Reproductive endocrinology report
Also known as
Proliferative phase
Contrasted with
Luteal phase
Don't confuse with
Luteal phase
Ovulatory phase
Menstrual phase