Why Are My Cycles So Short? Understanding Luteal Phase Health and Natural Progesterone Support

By: Dr. Alyssa McPeak

If you’ve noticed your cycle is getting shorter—maybe you're bleeding every 21 days or less—it’s easy to brush it off. But when you're trying to get pregnant, short cycles can be a red flag, especially if they come with spotting, mood swings, or early periods.

One of the most common causes of short cycles is a short luteal phase—and that often means low progesterone.

At Find Your Fertility, I want to help you get to the root of your hormonal imbalances, so you can optimize your cycle and boost your chances of getting pregnant naturally. Let’s dive into why your cycles might be short—and what you can do about it.

What Is a Short Cycle?

A normal menstrual cycle lasts between 26–35 days. Anything consistently shorter than 25 days is considered a short cycle.

Your cycle has two main phases:

1. Follicular Phase (first half, before ovulation)

2. Luteal Phase (second half, after ovulation)

A short cycle is usually the result of a shortened luteal phase—the time between ovulation and your next period. This phase should be at least 10–14 days long. Anything under 10 days may not allow enough time for a fertilized egg to implant, making it harder to get pregnant.

What Causes a Short Luteal Phase?

A short luteal phase often points to low progesterone. Progesterone is the hormone your body makes after ovulation to:

• Maintain the uterine lining for implantation

• Support early pregnancy

• Regulate mood and sleep

• Prevent early periods or spotting

When progesterone levels drop too early (or never rise enough), the lining sheds too soon—and your period arrives early.

Common root causes of low progesterone include:

• Chronic stress (hello, cortisol dominance)

• Undereating or overexercising

• Thyroid imbalances

• Poor ovulation or anovulatory cycles

• Inflammation or gut issues

• Perimenopause or hormonal shifts in your 30s+

How to Naturally Support Progesterone

The good news? There’s a lot you can do to nourish your body and help it produce more progesterone—naturally.

🌿 Nutrition + Lifestyle Tips:

✅ Eat enough—especially fats and protein. Your body needs dietary fat and cholesterol to make hormones. Don’t skip meals and don’t completely avoid vegetable-based carbs (especially root veggies during the luteal phase).

✅ Seed cycling. Incorporate sesame and sunflower seeds during your luteal phase to support progesterone production.

✅ Reduce stress. High cortisol steals the building blocks needed to make progesterone. Incorporate daily calming practices like deep breathing, walks, journaling, or chiropractic care.

✅ Support thyroid health. A sluggish thyroid can reduce progesterone. Make sure you’re getting enough iodine, selenium, and iron.

✅ Boost vitamin B6, magnesium, and vitamin C. These nutrients are key for ovulation and progesterone. You can get them through food or high-quality supplementation.

✅ Balance blood sugar. Blood sugar spikes and crashes wreak havoc on hormone production. Pair protein with every meal and reduce processed sugar.

✅ Get enough sleep. Your brain and ovaries communicate best when well-rested. Aim for 7–9 hours per night in total darkness.

Want to Learn More?

If you suspect low progesterone is affecting your cycle, I invite you to dive deeper with my course:

🎓 Cycle Syncing: A Step-by-Step Guide to Understanding and Supporting Your Hormones Inside, you’ll learn how to eat and live in sync with your cycle phases—especially how to support ovulation and increase progesterone naturally using food, lifestyle, and timing.

You’ll walk away with tools to:

• Lengthen your luteal phase

• Regulate your cycle

• Improve ovulation quality

• And boost your chances of getting pregnant—naturally.

💛 Your body’s short cycles are not random—they’re a message. With the right support, your hormones can find balance again. Start supporting your body today—one meal, one habit, one cycle at a time.

📲 Check out the Cycle Syncing Course and take the first step toward restoring your fertility.