The Moonlight Method

A Fertility Framework for Women Who Have Trouble Conceiving

Fertility has been under attack.  For the first time in modern history, conception is harder, miscarriage rates are higher, sperm counts are lower, menstrual cycles are more irregular, and pregnancy complications are more common.

We are living in an environment our biology did not evolve for. Chronic stress, unstable blood sugar, endocrine-disrupting chemicals, artificial light, inflammatory oils, mineral deficiencies, suppressed thyroid function. All of these can erode the systems that make reproduction possible. Fertility is not a single organ, it is the end result of metabolic health, hormonal precision, immune balance, and cellular energy. 

The body does not prioritize pregnancy when it senses instability. It prioritizes survival. Ovulation requires adequate energy.  Progesterone requires a functioning thyroid. Placental development requires proper vascular function. These are systems that require a lot of energy! 

Thankfully, there is a lot we can do to support proper energy production. The Moonlight Method is a hormone-supportive strategy for optimizing fertility, syncing with your body’s natural rhythms, and improving your chances of conception. It involves confirming ovulation, strategically applying progesterone, and nourishing your hormonal foundation with nutrients like Vitamin E, magnesium, vitamin D3K2, and thyroid support. This is not intended to be medical advice, but instead a framework.

Confirm Ovulation

The first step is to confirm that ovulation is actually happening. One of the easiest and most affordable ways to do this is by using ovulation predictor kits using pee sticks. 

Once you confirm ovulation (usually 24–36 hours after the peak), count 3 Days Past Ovulation (3 DPO). That’s when progesterone is usually started. 

Progesterone

Progesterone is the queen hormone of the second half of your cycle. It preps your uterine lining for implantation and keeps it stable in the early weeks of pregnancy. But if your body isn’t making enough, implantation can fail or the embryo may not be properly supported.

How Women Use It:

• Apply topical progesterone to areas like the forearms, abdomen, decolletage, or breasts starting at 3 DPO. Capsules can also be taken. 
• Continue until 12 DPO.
  • If you get a positive pregnancy test, continue using as directed by your doctor.
  • If your test is negative, stop and allow your period to come.

Progesterone for Miscarriage Prevention

Progesterone isn’t just important for implantation, it’s also a critical hormone for maintaining a pregnancy, especially in the early weeks. Low progesterone levels are one of the most common causes of first-trimester miscarriage. For women who have experienced one or more miscarriages, progesterone therapy can be a vital form of support.

In fact, research shows that progesterone supplementation may significantly improve live birth rates in women with a history of recurrent miscarriage. A study published by Tommy’s National Centre for Miscarriage Research found that:

Among 137 women with three or more previous miscarriages, 72% (98 women) who received progesterone had a live birth, compared with 57% (85 out of 148) in the placebo group.¹

According to Professor Arri Coomarasamy from the University of Birmingham:

“This treatment could save thousands of babies who may have otherwise been lost to a miscarriage. We hope that this evidence will be considered by the National Institute for Health and Care Excellence (NICE) and that it will be used to update national guidelines for women at risk of miscarriage.”

This study shows the powerful potential of progesterone as a safe, affordable, and accessible treatment to help prevent pregnancy loss in women with a history of miscarriage.

The Progesterone Baby Effect

The influence of progesterone might stretch even further into the emotional, intellectual, and neurological development of babies.

Dr. Katharina Dalton, a pioneer in progesterone therapy for women’s health, and Dr. Ray Peat, a biologist renowned for his research into hormones and metabolism, both supported the use of natural progesterone in pregnancy. Their work suggests that babies exposed to adequate progesterone in utero may develop enhanced cognitive abilities and a calmer, more resilient temperament.

At ages 9-10, headteachers assessed the children across various areas, including academic subjects, verbal reasoning, arithmetic, English, craftwork, and physical education.

The Findings:

• Progesterone group children consistently outperformed their peers in all academic subjects.
• They demonstrated higher verbal reasoning skills, better arithmetic performance, and more advanced craftwork abilities.
• Even in physical education, the progesterone-supported group had an edge.

This study, published in the British Journal of Psychiatry², highlighted that around 50% of progesterone children were rated above average in academic subjects, compared to significantly fewer in the control and toxemia groups.

Vitamin E 

Vitamin E is the fertility vitamin. The Greek word “tokos” (in tocopherol) means childbirth. Vitamin E behaves similarly to progesterone: it boosts oxygen to the uterus and embryo, counteracts excess estrogen, and even helps prevent menopause in aging animals. Vitamin E is a progesterone-sparing agent, meaning it helps extend and enhance the effects of your body’s natural progesterone. 

Magnesium 

A large percentage of U.S. adults do not get enough magnesium in their diets.³

Common symptoms of deficiency include muscle cramps, fatigue, brain fog, mood swings, constipation & irregular heartbeat. Most adults need around 300-400mg/day of magnesium, but stress can significantly raise requirements.⁴ Organ meats, well-cooked dark leafy greens, seafood, fruit and milk are good sources of magnesium, but many people find that a supplement is still needed for optimal levels.

Women with infertility have been found to have low blood levels of magnesium. In one study, women with a history of unexplained infertility and miscarriage all became pregnant and gave birth to healthy babies within 8 months of normalizing their red blood cell magnesium levels using a selenium, and magnesium supplement.⁵ Magnesium given during pregnancy has also been shown to reduce pre-eclampsia, preterm births and other complications.

Magnesium helps maintain a blood supply to the fetus by relaxing smooth muscles that line blood vessels. Magnesium is also needed to turn cholesterol into pregnenolone, progesterone—hormones required to stabilize the uterine lining so that the embryo can implant itself.

Raena’s Essential Magnesium is a great option. 

Thyroid 

An underactive thyroid can interfere with ovulation, shorten the luteal phase, or make it harder to maintain a pregnancy. Common signs of low thyroid function include cold hands and feet, fatigue, slowed metabolism, constipation, and brain fog.

The thyroid gland is often described as the body’s “spark plug” because it sets the pace for every cell’s metabolism. But its influence goes far beyond energy production. A well-functioning thyroid is critical for reproductive health, ovulation, and hormone balance, especially in women.

When the thyroid is underactive, a condition known as hypothyroidism, many downstream hormonal systems start to falter. This includes the delicate balance between estrogen and progesterone, which is essential for regular ovulation, a healthy luteal phase, and sustaining early pregnancy.

Low thyroid function can significantly affect fertility because thyroid hormones support the production of progesterone. When thyroid levels are low, progesterone often drops as well, and without adequate progesterone, it becomes much harder to sustain a healthy pregnancy.

A notable study conducted by Houston Methodist Neurological Institute and Erasmus Medical Centre found that pregnant women with insufficient thyroid hormone levels are nearly four times more likely to have children with autism. This research, published in Annals of Neurology, involved over 4,000 Dutch mothers and their children.⁶ It highlights how thyroid hormone plays a vital role in fetal brain cell migration during embryo development, which is a critical process for proper neurological wiring. When thyroid hormone levels drop too low, it can disrupt this process, contributing to neurodevelopmental disorders such as autism. 

Symptoms of Low Thyroid Function

When thyroid hormone levels are low, signs show up.

• Cold hands and feet (impaired circulation and low metabolic rate)
• Fatigue or sluggishness
• High cholesterol
• Brain fog, poor memory or slow thinking
• Dry skin, brittle nails, thinning hair
• Weight gain or inability to lose weight despite diet
• Constipation or slow digestion
• Irregular or heavy periods
• Depression or anxiety

If thyroid function is sluggish, many practitioners recommend Natural Desiccated Thyroid (NDT). Unlike synthetic T4-only medications (like levothyroxine), NDT contains a blend of T4, T3, T2, T1, and calcitonin, closely resembling what a healthy human thyroid would produce. This makes it a popular choice for people who don’t feel well on T4 alone, or whose bodies don’t convert T4 to T3 efficiently.

Aspirin

Aspirin, or more precisely acetylsalicylic acid, is a derivative of salicylic acid, a hormone found in plants. In the plant kingdom, salicylic acid functions similar to what progesterone does in the human body. It acts as a protective substance, defending plants against pathogens, reducing oxidative stress, and even increasing metabolic activity, which in turn improves growth and crop resilience. 

In humans, progesterone serves a very similar set of roles: it’s a pro-metabolic, anti-stress, anti-inflammatory, and neuroprotective hormone. It calms the nervous system, supports immune function, opposes cortisol and estrogen, and increases the efficiency of oxygen and glucose metabolism at the cellular level. 

Low-dose aspirin is used clinically in pregnancy. For women at risk of preeclampsia, a potentially life-threatening pregnancy complication characterized by high blood pressure and organ dysfunction, low-dose aspirin is one of the most effective and simple interventions. 

From a metabolic perspective, preeclampsia reflects stress at the level of the placenta. This could be in the form of increased inflammatory prostaglandins, excessive platelet activation, oxidative stress, and reduced oxygen delivery. Aspirin works by gently inhibiting cyclooxygenase (COX) enzymes, which lowers thromboxane A₂, a compound that promotes clotting and blood vessel constriction. In doing so, it improves microcirculation and supports better blood flow to the placenta. Better blood flow means better oxygen delivery, improved mitochondrial respiration, and less reliance on stress-driven metabolism. For this reason, baby aspirin is commonly started between 12 and 16 weeks of pregnancy and continued until at least 36 weeks in women at elevated risk. Rather than functioning simply as a “blood thinner,” low-dose aspirin can be understood as a metabolic stabilizer.

For women with a family history of preeclampsia or other risk factors, baby aspirin is now considered standard preventive care. Even in women with no history of elevated blood pressure, but a strong family background, it’s often recommended to minimize the risk of placental insufficiency, restricted fetal growth, and hypertensive disorders later in gestation.

Vitamin D3K2

Adequate vitamin D levels during pregnancy are essential for the health of both mother and baby. Sufficient vitamin D supports maternal well-being, proper fetal bone development, and healthy pregnancy progression. Low vitamin D levels during pregnancy and early infancy have been linked to complications such as preeclampsia, low birth weight, neonatal hypocalcemia, impaired early growth, reduced bone strength, and a higher risk of autoimmune conditions later in life.⁸

Here are some important stats: 

• Low levels of vitamin D (under 20ng/mL) are associated with high levels of miscarriage.⁷ Studies have shown that 1,000-10,000 IU/day vitamin D3 from a supplement can improve pregnancy rates in infertile women.⁹
• PCOS is one of the leading causes of infertility in women. Vitamin D insufficiency is highly prevalent in women with PCOS, with one study finding that nearly 73% had levels below 30 ng/mL, and lower vitamin D levels were associated with greater insulin resistance and metabolic dysfunction.¹⁰
• More than half of pregnant women worldwide have vitamin D levels below 20 ng/mL, with prevalence exceeding 80% in some regions.¹¹
• Maternal vitamin D levels ≥40 ng/mL have been associated with approximately 50–60% lower risk of preterm birth compared with levels below 20 ng/mL.¹²
• Women with vitamin D levels ≤30 ng/mL had significantly higher rates of primary cesarean section (40.9%) compared with women whose levels were above 30 ng/mL (12.8%).¹³

One of the deeper reasons vitamin D matters in pregnancy has to do with mineral balance and parathyroid hormone (PTH), something Dr. Ray Peat often emphasized. As he noted:

“When vitamin D or calcium is deficient, or when phosphate is excessive, and in hypoglycemia and stress, parathyroid hormone increases… This can lead to softening of bones, and hardening of soft tissues… Parathyroid hormone increases blood pressure, even before the calcium stiffening is detected.”¹⁴

In simple terms, vitamin D helps regulate calcium metabolism. When vitamin D is low, the body cannot absorb calcium efficiently from the diet. In response, parathyroid hormone rises in an attempt to maintain normal blood calcium levels. It does this by pulling calcium out of bone and increasing calcium mobilization. Over time, this can weaken skeletal structure while simultaneously promoting inappropriate calcium deposition in soft tissues.

During pregnancy, this regulatory system becomes even more critical. The developing baby requires large amounts of calcium for skeletal growth. If maternal vitamin D is insufficient, PTH may rise to compensate. Elevated PTH is a stress signal. It increases vascular tone, raises blood pressure, and can contribute to endothelial dysfunction.

Rather than thinking of vitamin D simply as a “bone vitamin,” it may be more accurate to see it as a regulator of mineral balance, vascular stability, and metabolic resilience — all of which are foundational for a healthy pregnancy.

The Foundations

And of course, the foundation of health has to be the basics. Pregnancy is metabolically demanding. The body cannot build a placenta, expand blood volume, grow a baby, and maintain maternal resilience without sufficient raw materials and steady energy. Optimizing the fundamentals creates the terrain where everything else works better.

Sufficient protein is non-negotiable. Pregnancy increases protein requirements significantly because protein supplies the amino acids needed for fetal growth, placental development, blood volume expansion, immune regulation, and hormone production. High-quality sources such as shrimp, cod, grass-fed steak, eggs, and dairy provide complete amino acid profiles. Protein also stabilizes blood sugar, which helps reduce stress hormones like cortisol and adrenaline — both of which can interfere with thyroid function and progesterone production if chronically elevated.

Sufficient fruit provides easily metabolized carbohydrates along with potassium, vitamin C, and protective polyphenols. Oranges, strawberries, melons, and other ripe fruits help maintain liver glycogen stores. When blood sugar drops, the body raises cortisol and adrenaline, and chronic stress signaling can suppress thyroid function and raise parathyroid hormone.

Adequate carbohydrate intake supports thyroid hormone conversion (T4 to T3), lowers stress hormones, and reduces the need to rely on excessive fat oxidation, which can increase inflammatory byproducts when unstable polyunsaturated fats dominate the diet. 

High-quality dairy offers calcium, protein, and often vitamin D (if fortified), all of which support bone integrity and regulate parathyroid hormone. Calcium sufficiency helps prevent the stress-driven rise in PTH that can affect vascular tone and blood pressure. Milk, yogurt, and cheese (if well tolerated) can be uniquely protective during pregnancy because they supply a highly bioavailable mineral matrix alongside protein and carbohydrates.

Daily sunlight is foundational for vitamin D production. Sensible sun exposure helps maintain optimal 25(OH)D levels, supporting immune regulation, placental development, vascular stability, and mineral balance. 

At the same time, reducing metabolic stressors matters. Certain foods are considered anti-thyroid because they can interfere with thyroid hormone production or utilization, particularly when consumed in excess or in raw forms. These include large amounts of soybeans, peanuts, raw cruciferous vegetables (like cabbage, broccoli, cauliflower, radishes), and industrial seed oils high in polyunsaturated fatty acids (safflower, corn, cottonseed, soybean oil). Excessive iodine can also disrupt thyroid balance in susceptible individuals. 

Fertility reflects what’s going on inside the body. When ovulation is confirmed, progesterone is supported, thyroid function is steady, minerals are sufficient, inflammation is reduced, and energy production is strong, the body is far more likely to sustain conception and early pregnancy. 

Citations: 

1. Tommy’s National Centre for Miscarriage Research. (2020, January 31). Giving some pregnant women progesterone could prevent 8,450 miscarriages a year, say experts – press release. Tommy’s. 
2. Dalton K. (1968). British Journal of Psychiatry. 114(516): 114, 1377.
3. Rosanoff A, Weaver CM, Rude RK. Suboptimal magnesium status in the United States: are the health consequences underestimated? Nutr Rev. 2012;70(3):153–164.
4. DiNicolantonio JJ, O’Keefe JH, Wilson W. Magnesium and Stress: The Stress Response and the Need for Magnesium. Open Heart. 2018;5(2):e000668. Magnesium requirements are generally ~300–400 mg/day for adults, with stress significantly increasing needs.
5. Howard JM, Davies S, Hunnisett A. Red cell magnesium and glutathione peroxidase in infertile women—effects of oral supplementation with magnesium and selenium. Magnesium Research. 1994 Mar;7(1):49–57. PMID: 8054261.
6. Román GC, et al. Association of gestational maternal hypothyroxinemia and increased autism risk. Ann Neurol. 2013;74(5):733–742.
7. Andersen LB, Jørgensen JS, Jensen TK, Dalgård C, Barington T, Nielsen J, et al. Vitamin D insufficiency is associated with increased risk of first-trimester miscarriage. Hum Reprod. 2015;30(2):452–460.
8. Zhang H, Wang S, Tuo L, et al. Relationship between maternal vitamin D levels and adverse outcomes. Nutrients. 2022;14(20):4230. PMID: 36296914; PMCID: PMC9610169.
9. Meng X, Zhang J, Wan Q, Huang J, Han T, Qu T, Yu L-L. Influence of vitamin D supplementation on reproductive outcomes of infertile patients: a systematic review and meta-analysis. Reprod Biol Endocrinol. 2023;21:17. doi:10.1186/s12958-023-01068-8. PMID: 36737817; PMCID: PMC9896710.
10. Wehr E, Pilz S, Schweighofer N, et al. Association of hypovitaminosis D with metabolic disturbances in polycystic ovary syndrome. Eur J Endocrinol. 2009;161(4):575–582.
11. Saraf R, Morton SMB, Camargo CA Jr, Grant CC. Global summary of maternal and newborn vitamin D status – a systematic review. Matern Child Nutr. 2016;12(4):647–668.
12. McDonnell SL, Baggerly KA, Baggerly CA, et al. Maternal 25(OH)D concentrations ≥40 ng/mL associated with 60% lower preterm birth risk among general obstetrical patients at an urban medical center. PLoS One. 2017;12(7):e0180483. doi:10.1371/journal.pone.0180483.
13. Hubeisha M, Al Husari H, Itani SE, El Tala R, Tamim H, Abou Saleh S. Maternal vitamin D level and rate of primary cesarean section: a prospective cohort study. J Clin Gynecol Obstet. 2018;7(2):43–51.
14. Ray Peat Newsletter. September 2017.

Remember: this post is for informational purposes only and may not be the best fit for you and your personal situation. It shall not be construed as medical advice. The information and education provided here is not intended or implied to supplement or replace professional medical treatment, advice, and/or diagnosis. Always check with your own physician or medical professional before trying or implementing any information read here.