Short Luteal Phase: Causes, Symptoms and Natural Support

What Is the Luteal Phase?

The luteal phase is the second half of your menstrual cycle, beginning after ovulation and ending when your period starts. During this phase, the corpus luteum (the structure left behind after the egg is released) produces progesterone, which is essential for¹:

• Thickening the uterine lining for implantation
• Supporting early pregnancy
• Maintaining the pregnancy until the placenta takes over

A normal luteal phase typically lasts 12-14 days. A short luteal phase (also called luteal phase defect or LPD) is generally considered to be 10 days or fewer.

Why Does Luteal Phase Length Matter?

If your luteal phase is too short, several problems can occur:

• Implantation failure – The fertilised egg may not have enough time to implant before your period begins
• Early miscarriage – Insufficient progesterone can lead to early pregnancy loss
• Difficulty conceiving – Even if fertilisation occurs, the pregnancy may not establish

For more on understanding your cycle, read: Understanding Your Menstrual Cycle.

Signs and Symptoms of a Short Luteal Phase

You might have a short luteal phase if you experience:

• Spotting between ovulation and your period
• Periods that arrive earlier than expected
• Difficulty getting pregnant despite regular ovulation
• Recurrent early miscarriages
• Light periods
• Premenstrual spotting for several days before your period

What Causes a Short Luteal Phase?

Several factors can contribute to a shortened luteal phase:

Hormonal Imbalances

• Low progesterone – The corpus luteum doesn't produce enough progesterone
• Thyroid dysfunction – Both hypothyroidism and hyperthyroidism can affect the luteal phase
• High prolactin – Elevated prolactin levels can suppress progesterone production
• PCOS – Polycystic ovary syndrome can affect ovulation quality and luteal phase length

Lifestyle Factors

• Chronic stress – High cortisol can suppress progesterone
• Excessive exercise – Particularly in underweight individuals
• Poor nutrition – Inadequate nutrients to support hormone production
• Being underweight or overweight – Both can affect hormone balance

Age

As women approach their late 30s and 40s, luteal phase defects become more common due to declining egg quality and changes in hormone production².

How Is a Short Luteal Phase Diagnosed?

There are several ways to identify a luteal phase issue:

Cycle Tracking

Track your basal body temperature (BBT) and/or use ovulation predictor kits to identify when you ovulate. Count the days between ovulation and the start of your next period.

Progesterone Blood Test

A blood test taken around day 21 of your cycle (or 7 days after ovulation) can measure your progesterone levels. Low levels may indicate a luteal phase defect.

Ultrasound Monitoring

Your doctor may monitor follicle development and the corpus luteum via ultrasound.

For more on testing, see: Fertility Tests Explained.

Natural Ways to Support Your Luteal Phase

Several lifestyle and nutritional strategies may help lengthen your luteal phase and support healthy progesterone levels:

Vitamin B6

Vitamin B6 is essential for progesterone production and may help extend the luteal phase³. Good food sources include poultry, fish, potatoes, and bananas. Our Vitafem contains B vitamins including B6, as well as other vitamins and minerals to support egg health, hormone balance, and overall preconception wellness.

Vitamin C

Research suggests vitamin C may help increase progesterone levels. Found in citrus fruits, peppers, and berries.

Vitamin D

Low vitamin D has been linked to hormonal imbalances. Our Vitamin D spray delivers fast absorbing, spray form of Vitamin D to support fertility. This sublingual spray is a highly absorbable supplement designed to support female fertility. As a convenient spray format, it delivers 1000iu (25ug) Vitamin D levels to help regulate hormones, support egg quality,

Zinc

Important for hormone production and ovarian function. Good sources include shellfish, meat, and pumpkin seeds.

Stress Reduction

Chronic stress elevates cortisol, which can suppress progesterone. Consider:

• Yoga or meditation
• Regular gentle exercise
• Adequate sleep
• Setting boundaries

Read more: The Importance of Stress Management When Trying for a Baby.

Healthy Fats

Cholesterol is the building block for hormones including progesterone. Include healthy fats from avocados, olive oil, nuts, and oily fish. Our Vital DHA provides omega-3 fatty acids.

Medical Treatments

If lifestyle changes aren't enough, your doctor may recommend:

• Progesterone supplementation – Taken after ovulation to support the luteal phase
• Clomiphene citrate or letrozole – To improve ovulation quality
• hCG injections – To support the corpus luteum
• Treating underlying conditions – Such as thyroid disorders or PCOS

Frequently Asked Questions

How short is too short for a luteal phase?

A luteal phase of 10 days or fewer is generally considered too short for successful implantation and pregnancy maintenance. The ideal length is 12-14 days.

Can you still get pregnant with a short luteal phase?

Yes, it's possible, but a short luteal phase can make it more difficult to conceive and may increase the risk of early miscarriage. Treatment can significantly improve your chances.

How do I know if my luteal phase is too short?

Track your ovulation using BBT charting or ovulation predictor kits, then count the days until your period starts. If it's consistently 10 days or fewer, speak to your GP or fertility specialist.

Can supplements fix a short luteal phase?

Some supplements, particularly vitamin B6 and vitamin C, may help support progesterone production and lengthen the luteal phase. However, if there's an underlying condition, you may also need medical treatment.

Does vitex (chasteberry) help with luteal phase defect?

Some research suggests vitex may help regulate the menstrual cycle and support progesterone levels⁴. However, you should consult a healthcare provider before taking it, especially if you're also using other fertility treatments.

When to Seek Help

Consult your GP or a fertility specialist if:

• Your luteal phase is consistently 10 days or shorter
• You've been trying to conceive for 6-12 months without success
• You've experienced recurrent early miscarriages
• You have irregular cycles or other symptoms of hormonal imbalance

Through our own clinical practice, we know the best fertility support should be personal, not one-size-fits-all. That's why our unique supplement range is built to be flexible and targeted, and we offer free 1:1 consultations with experienced fertility nutritionists to help you get the most out of it.

References

1. Sonntag B, Ludwig M. An integrated view on the luteal phase: diagnosis and treatment in subfertility. Clin Endocrinol. 
2. Practice Committee of the American Society for Reproductive Medicine. Current clinical irrelevance of luteal phase deficiency. Fertil Steril.
3. Retallick-Brown H, et al.A Pilot Randomized Treatment-Controlled Trial Comparing Vitamin B6 with Broad-Spectrum Micronutrients for Premenstrual Syndrome. Journal of alternative and complimentary medicine.
4. Westphal LM, et al. A nutritional supplement for improving fertility in women. J Reprod Med. 

If you're concerned about your luteal phase or fertility, please consult your GP or a fertility specialist. This article is for informational purposes only.