EnglishNorwegian

Infertility

Infertility is defined as the inability to conceive after 12 months of regular, unprotected intercourse in women less than 35 years of age or after 6 months in women over 35 years of age. Abnormalities in menstruation, fertility, and early pregnancy maintenance in female shift workers provide evidence for a role of circadian rhythms in the reproductive health of women. Circadian rhythms disruption is highly associated with melatonin deficiency and infertility.

INFERTILITY RELATED TO CIRCADIAN RHYTHMS

With the advent of modern technology and an around the clock work schedule, a significant shift in our daily behavior has been possible. Night shift work, travel across multiple time zones and exposure to bright lights at night hours disrupt the circadian rhythms and suppress production and secretion of melatonin. Studies show that both stable circadian rhythms and timely availability of melatonin are critical for optimal ovarian physiology as well as male reproductive function.

Circadian rhythms impact on a wide range of physiological systems and this impact extend to fertility, such that disruptions to timing systems can impact upon reproductive capacity.  Women with ovulatory menstrual cycles have a circadian rhythm superimposed on the menstrual-associated rhythm; in turn, menstrual events affect the circadian rhythm. This suggests an intersection between the circadian rhythm and the monthly rhythms related to fertility.

When the multiple rhythms and cycles that control our bodies are aligned, we benefit from optimal health, including maximum fertility. When these cycles become misaligned, our health and fertility can suffer. A recent study found that jet lag and other circadian rhythm disorders can have negative effects on fertility. Researchers believe that a disruption in melatonin production is the root of this issue.

 

 

Stable circadian rhythms and timely availability of melatonin are critical for optimal ovarian physiology as well as male reproductive function.

Melatonin

Melatonin has been proven to affect sleep-wake patterns, cell growth and a variety of cell pathways, and new studies indicate it may control female fertility as well. Our bodies run on a variety of rhythms, including a 24-hour circadian rhythm and a seasonal rhythm. Women’s bodies also have a monthly cycle that governs female fertility. These cycles may be more intertwined than previously believed, with melatonin acting as the link that ties them together.

Because ovarian function is crucial to a woman’s fertility, stable circadian rhythms can influence a woman's chance of achieving a healthy pregnancy. Melatonin has a variety of effects on the ovaries. It acts as an antioxidant to this important tissue and therefore prevents cell damage which in turn is increasing egg quality, a crucial factor in fertility. Women undergoing IVF who take melatonin supplements have a higher likelihood of getting pregnant and giving birth to a healthy baby.

 

Sleep

It is estimated that approximately 30% of women 25–44 years of age sleep less than or equal to 6 hours in a 24-hour day, despite joint consensus recommendations for 7–8 hours of sleep per night.

Multiple pathways exist by which sleep and circadian rhythms may influence fertility. Disrupted sleep may modify hormone secretion which could have negative repercussions on ovulatory cycles. Insufficient sleep duration, or sleep disrupted by obstructive sleep apnea, may result in insulin resistance and glucose intolerance potentially contributing to infertility and early pregnancy loss.

Reproductive hormones may modify sleep, and the relationship is bidirectional such that sleep disruption may alter the profile of reproductive hormone secretion. Therefore, sleep, apart from its circadian timing, may also have relevance in attaining pregnancy.

Additionally, infertility is associated with psychological distress which may result in poor quality sleep. The interaction between psychological distress and disturbed sleep in reproduction may be a crucial factor to consider during the evaluation and treatment of infertility.  

Finally, sleep may impact sexual behavior. In a recent investigation, sleep duration was associated with sexual desire and genital response. With every 1-hour increase in total sleep time, a 14% increase in the odds of partnered sexual activity was seen. Greater genital arousal was reported in women with longer average sleep time.

Multiple pathways exist by which sleep and circadian rhythms may influence fertility.

Shift Work

We become an increasingly 24-hour society, misalignment between our endogenous circadian rhythm and external light-dark schedule may impair reproductive health as evident in female shift workers. These epidemics underscore the need to understand the role of insufficient, disturbed, or mistimed sleep in infertility.

In shift work (particularly night work), the work period occurs when the circadian timing system promotes sleep and the time allotted for sleep overlaps with the time of high circadian alerting signal. Together, this results in sleep deprivation and misalignment between the endogenous circadian system and externally imposed light-dark cycle. This desynchrony has negative repercussions for physiological function as circadian oscillators are spread throughout the periphery.

Disruption of circadian rhythms is associated with disturbances in menstrual function. Female shift workers compared to non-shift workers are more likely to report menstrual irregularity and longer menstrual cycles, which may reflect problems with ovulation.

Disruption of circadian rhythms is associated with disturbances in menstrual function.

HOW CIRCADIAN EYEWEAR CAN HELP INFERTILITY

Circadian Eyewear is a medical device which eliminates the blue wavelengths from reaching the retina. Wearing Circadian Eyewear two hours before the scheduled sleep time can help entrain the circadian rhythms, regulate sleep duration and quality, and help the timely production and secretion of melatonin.

While there are multiple factors that influence the chance of getting pregnant, studies show that both stable circadian rhythms and timely availability of melatonin are critical for optimal ovarian physiology as well as male reproductive function.

Circadian Eyewear Collection
Circadian Eyewear

 

 

 

 

RESEARCH REGARDING FERTILITY TIED TO CIRCADIAN RHYTHMS

Research from  PubMed
Circadian rhythms and fertility

Melatonin and the circadian system: contributions to successful female reproduction.

Cortisol, estradiol-17β, and progesterone secretion within the first hour after awakening in women with regular menstrual cycles.

The uterus sustains stable biological clock during pregnancy.  

Relationship between psychological stress and reproductive outcome in women undergoing in vitro fertilization treatment: psychological and neurohormonal assessment.

Self-reported sleep across the menstrual cycle in young, healthy women.

Circadian rhythms, sleep, and the menstrual cycle.

Influence of partial sleep deprivation on the secretion of thyrotropin, thyroid hormones, growth hormone, prolactin, luteinizing hormone, follicle stimulating hormone, and estradiol in healthy young women.

Circadian regulation of reproduction: from gamete to offspring.

Actigraphic and self-reported sleep quality in women: associations with ovarian hormones and mood.

Circadian clock mutation disrupts estrous cyclicity and maintenance of pregnancy.

Oral melatonin supplementation improves oocyte and embryo quality in women undergoing in vitro fertilization-embryo transfer.

Circadian variation in concentration of anti-Müllerian hormone in regularly menstruating females: relation to age, gonadotrophin and sex steroid levels.

A pilot double-blind randomised placebo-controlled dose-response trial assessing the effects of melatonin on infertility treatment (MIART): study protocol.

Sex hormone receptors are present in the human suprachiasmatic nucleus.

Circadian clock gene plays a key role on ovarian cycle and spontaneous abortion.

 

Research from Chronobilogy
Biological Rhythms and How They Affect a Woman's Fertility

Research Sources