What is the luteal phase?

Bottom lineThe luteal phase is the second half of the cycle, from ovulation to your next period, when the corpus luteum produces progesterone to thicken and stabilize the uterine lining and basal body temperature rises; it's fairly consistent at about 12 to 14 days, is when PMS symptoms appear, and ends with a progesterone drop that triggers your period if no pregnancy occurs.

The luteal phase is the second half of your cycle, from ovulation until your next period. It's when your body prepares for a possible pregnancy.

What happens

• After ovulation, the empty follicle becomes the corpus luteum, which produces progesterone
• Progesterone thickens and stabilizes the uterine lining for a potential embryo
• Your basal body temperature rises slightly (a sign ovulation happened)
• If no pregnancy occurs, the corpus luteum breaks down, progesterone drops, and your period begins

How long it lasts

The luteal phase is fairly consistent at about 12 to 14 days, unlike the variable follicular phase. A luteal phase shorter than about 10 days is called a short (or luteal phase) defect and can occasionally affect fertility.

How you might feel

The progesterone-dominant luteal phase is when PMS symptoms appear - bloating, breast tenderness, mood changes - especially in the final days as hormones fall.

Why it matters

Because the luteal phase length is stable, it's the anchor used to estimate ovulation from your cycle length.

See what is a short luteal phase and the four cycle phases.

Femora uses your luteal phase timing to predict your next period and fertile window.