Written by: Dr. Amy Beckley, PhD, Founder and Inventor of the Proov test — the first and only FDA-cleared test to confirm successful ovulation at home.
Your menstrual cycle has 2 main phases:
- The follicular or pre-ovulatory phase
- The luteal or post-ovulatory phase
As the latter half of your cycle, the luteal phase comes after release of the egg, a.k.a. ovulation. It begins the day after ovulation and ends the day before a new cycle starts with menstrual flow. Think: luteal = last half of the cycle.
The luteal phase comes after the release of the egg.
The term “luteal” comes from the Latin word for “yellowish” or luteum which refers to the “yellow body” or corpus luteum that is formed from the follicle that emptied itself when it released its egg. An empty follicle becomes the corpus luteum which makes the hormones that govern the luteal phase. The main hormone in the luteal phase is progesterone. There’s also a bit of estrogen at play in the luteal phase.
During the luteal phase, the lining of the uterus (endometrium) gets a break from the thickening that occurs in the follicular phase. Instead, the endometrium focuses on being stable and increasing blood supply to the thickened lining. Stability and increased blood supply means valuable nutrients and oxygen are going to uterine lining in preparation for possible pregnancy.
If pregnancy does not occur, the corpus luteum will fade away about two weeks after ovulation. As it fades, progesterone levels will drop. This signals the de-stabilization and shedding of the lining of the uterus. This is what we call menstruation. Menstruation means your luteal phase is over. You’re back to the follicular phase of a new cycle.
To learn more about the phases of the menstrual cycle, check out this post called “Know the Parts of Your Cycle.”
Why is the luteal phase important?
The luteal phase is important because it’s when implantation and the start of pregnancy will occur if you conceived. Implantation requires a stable endometrium and this stability is supported by a strong corpus luteum. A strong corpus luteum makes adequate progesterone, the hormone that literally means “for pregnancy”, or pro-gestation.
Beyond supporting implantation and early pregnancy, you should keep tabs on your luteal phase because its very existence means you ovulated! You can’t have a luteal phase without ovulation because you don’t get an empty follicle which then becomes the corpus luteum without ovulation. Ovulation is a sign of health, balanced hormones, and fertility. It’s also the pivot point of your cycle, ending the follicular phase and ushering in the luteal phase.
Awareness of your luteal phase can also help you understand your health and fertility. Recent studies have linked a short luteal phase to PMS, PMDD, and an increased risk of early miscarriage. The physiologic explanation for this link lies in the benefits of progesterone that is made primarily in the luteal phase.
Progesterone is thought to affect more than the lining of the uterus; It appears to have brain and mood benefits as well! This luteal phase hormone helps reproductive-aged women stay calm as they approach menstruation. Maybe it has something to do with a stable uterine lining supporting a stable mood? Who knows!?
You can read more about the link between luteal phase progesterone and miscarriage here.
Read more about the mental health impact of progesterone here.
Progesterone impacts more than just your uterine lining.
How long should my luteal phase be?
Generally speaking, you want your luteal phase to be 11-17 days long. This means that you, your brain, and your uterine lining have adequate exposure to progesterone from the corpus luteum which formed from the follicle which released an egg. Adequate exposure to progesterone means fewer PMS or PMDD symptoms and reduced risk of early miscarriage.
Once you measure the length of one luteal phase, keep it going! It’s good to know if your luteal phase changes in length over the course of a few cycles. Your post-ovulatory or luteal phase length should remain relatively stable from one cycle to the next.
To know if you have a stable luteal phase length track ovulation, which will allow you to track your luteal phase length because it starts the day after ovulation. A constant variability of more than 1-2 days in luteal phase length deserves attention.
Reminder: You need to have an accurate sense of when you ovulated in order to know your luteal phase length. Most women do not know when, or even if, they ovulate and that’s okay. Proov Ovulation Predictor Kits are here to help with knowledge of ovulation.
What should I do if I have a short luteal phase?
You are not alone. If your luteal phase is consistently shorter than 11 days, you have options. Consistently is an operative word here. At least two consecutive cycles with luteal phases less than 11 days is what’s meant by consistently.
First and foremost, talk to your doctor. You want them to be aware of your cycle health and recommend assessments and care plans to help you get to the bottom of a short luteal phase. If you have symptoms of PMS or PMDD be sure to report them to your doctor.
If you have fertility goals, it’s a good idea to include them in your discussion about your luteal phase. Any history of early pregnancy loss is also important to mention when you talk to your doctor about a short luteal phase. Aim to work with a doctor who values your knowledge of your cycle and shares your goal of restoring hormonal balance and a healthy luteal phase.
Along with seeking professional help, stay on top of your luteal phase by testing your progesterone or PdG levels in the comfort of your own home. Proov Confirm PdG tests confirm that successful ovulation has occurred. Learn more about this in-home test here.
You can also consider a few strategic lifestyle changes. These may include:
- Seed cycling: Eating sesame and sunflower seeds in the luteal phase may help with progesterone production.
- Eliminating light exposure at night: Research shows that ovulation and luteal phase length can be affected by exposure to light while we sleep.
- Herbal supplements under the guidance of a qualified women’s health professional
Vitex, maca, and ashwagandha are a few herbal supplements that may help with a short luteal phase. Check this must-read article if you are considering supplementation with herbs.
Did this help you understand the luteal phase? Let us know!
