The luteal phase: what's happening in your body and mood

The luteal phase is the second half of your menstrual cycle. It starts right after ovulation, when the follicle that released your egg collapses into a temporary gland called the corpus luteum, and ends the day before your period starts.

Its job is to produce progesterone, the hormone that keeps the uterine lining ready in case the egg is fertilized. If there's no pregnancy, the corpus luteum breaks down, progesterone falls, and the lining sheds as your period.

The luteal phase is the mirror of the follicular phase that comes before ovulation. Where the follicular phase is about estrogen rising to prepare an egg, the luteal phase is about progesterone rising, then falling, to prepare and then release the lining. Most of what's known as PMS happens here, in the second half of the cycle, not the first.

The luteal phase starts the day after ovulation and ends the day before your next period. For most women it lasts somewhere between 11 and 17 days (ACOG Clinical Practice Guideline No. 7, 2023), and it's far steadier than the first half of the cycle, which can stretch or shrink by a week or more depending on when you ovulate.

A luteal phase that's unusually short for several months in a row is something to bring up with a doctor. Some research has linked it to fertility difficulty, though experts disagree on how much it matters on its own. A single short or long cycle usually isn't a concern. A pattern over several months is worth tracking.

Because the luteal phase length is fairly fixed for you personally, it's the easiest part of the cycle to predict once you know your pattern. The luteal phase length guide walks through what counts as short, typical or long, how to count it from your own cycles, and when to mention it to a doctor.

Progesterone is the headline hormone. It rises for about a week after ovulation, plateaus, then drops sharply in the final days before your period if you're not pregnant. Estrogen also rises again in the luteal phase, though to a lower second peak than at ovulation, and falls alongside progesterone at the end.

One progesterone breakdown product, allopregnanolone, matters a lot for mood. It acts on GABA receptors in the brain, the same system calmed by anti-anxiety medications, which is part of why the hormone shifts here can affect how settled or on edge you feel.

Cortisol, the main stress hormone, also behaves differently across the cycle. A meta-analysis of 778 women found cortisol levels were lower in the luteal phase than the follicular phase (Frontiers in Endocrinology, 2020). This may be connected to the way allopregnanolone and cortisol regulate each other, though the link to mood symptoms isn't settled.

For the full hormone-by-hormone breakdown, see hormones in the luteal phase.

Common luteal phase symptoms, roughly in order of how often women report them:

• Breast tenderness and bloating
• Fatigue or low energy
• Food cravings, especially for carbohydrates and fat
• Headaches
• Mood changes: irritability, low mood, anxiety, or feeling more sensitive to rejection
• Trouble sleeping

Most of these are mild and ease within a day or two of your period starting. That pattern, physical and emotional symptoms that resolve once bleeding begins, is what defines PMS.

For a smaller group of women, the late luteal phase brings something sharper. A study comparing women with PMDD to women without found that in the late luteal phase, the PMDD group ate noticeably more high-fat food and performed worse on word and digit recall tasks than in their own follicular phase or compared with controls (Hormones and Behavior, 2008). Mood dropped sharply in that same window, while the control group's mood barely moved.

Mood changes here come from the hormone drop, not the hormone level. Estrogen and progesterone fall every cycle in the days before a period, and that fall briefly changes GABA signaling in the brain through allopregnanolone. Most women notice this as mild moodiness. Some brains react to that same drop far more strongly, and that difference in sensitivity, not an abnormal hormone level, is at the center of PMDD (Schmidt et al., 1998, NEJM; Dubey et al., 2017, Molecular Psychiatry).

There's evidence this heightened reactivity shows up outside of mood too. In one study, women with PMDD startled more easily than controls in both cycle phases, and lost more of their normal filtering of a sudden loud noise specifically in the late luteal phase (Neuropsychopharmacology, 2008). That points to a brain and body that react more strongly all month, with the late luteal phase as the point where it shows most.

Mood state and personality aren't the same thing. A study comparing women with what was then called late luteal phase dysphoric disorder to controls found no significant effect of cycle phase on personality traits measured outside of mood symptoms (Psychological Medicine, 1996). The irritability or tearfulness you feel in the luteal phase is a hormone-driven state, not a change in who you are.

Day to day, a few things reliably take the edge off:

• Protein and fiber at each meal, rather than skipping meals, to blunt energy crashes and cravings
• Regular sleep timing, since sleep tends to get lighter and shorter in the luteal phase
• Movement most days, even a 20-minute walk
• Less alcohol in the week before your period, since it can worsen sleep and next-day mood

For symptoms that interfere with daily life, hormonal options are worth discussing with a doctor. Combined hormonal contraception affects mood differently depending on the week. One placebo-controlled trial found small increases in anxiety, irritability and mood swings on regular active-pill days, but an improvement in depressive symptoms during the premenstrual days of the active pill (Psychoneuroendocrinology, 2017). It doesn't work the same way for everyone.

For PMDD specifically, guidelines support SSRIs, which some women take only during the luteal phase rather than every day. A small trial found this intermittent dosing worked as well as or better than continuous daily dosing for reducing irritability (Journal of Clinical Psychopharmacology, 1998). A doctor decides what, if anything, is right for you.

If what you need right now is somewhere to put a fight or a wave of tears before you act on it, Niyora is a PMS and PMDD support app. Its Moon feature lets you write down what happened, see it from another angle, calm down, and draft a reply you can hold onto for 20 minutes instead of sending right away.

If your mood only shifts in the second half of your cycle, starting in the week before your period and easing within a few days of it beginning, that pattern is a clue. It doesn't confirm PMDD by itself, since most women notice some mood change in the luteal phase.

PMDD is a specific diagnosis in the DSM-5-TR and ICD-11. It requires at least five symptoms in the final week before your period, with at least one being a mood symptom (mood swings or rejection sensitivity, irritability or anger, low mood, or anxiety). Symptoms need to ease within a few days of bleeding starting and stay minimal the week after. Doctors confirm it with daily symptom ratings over at least two cycles, not a single hard month.

This pattern leans toward PMDD rather than PMS when the symptoms are severe enough to disrupt work, relationships or daily function. Premenstrual exacerbation can look similar, but the underlying condition, often depression or anxiety, is present all month and worsens before your period.

Read more on PMDD and how it's diagnosed.