According to the recent moon phase trendon TikTok,video sex kiss party you can figure out whether you and your partner are MFEO if your birth moons form a "perfect" full moon.

Well, astrologers say that's not the whole story. "This isn't really valid," said astrologer and author Lisa Stardust, who created a Love Deckof cards. "It has more to do with the zodiac sign of the moon and the whole chart together. It's not [as] simple as just the lunar phase."

"I'm not sure if I agree with that TikTok trend," agreed astrologer Alice Bell, author of the upcoming Trust Your Timing, a book about relationship astrology. 

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We asked the experts to break down the symbolism of the moon phases — and what really determines moon compatibility. 

What do the moon phases mean?

"As the moon grows from new to full it brings us enlightenment and growth," Stardust said. "The moon's phases help us evolve as people and understand our individual needs and the needs of the collective."

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Additionally, cultural and symbolic associations have developed over time in terms of how the moon may impact sexual behavior, said psychologist, tarot card reader, and astrologer Matthias Dettmann. Here are the phases of the moon, what they can mean generally and in sex and relationships, according to Dettmann:

New Moon

"This is a time of new beginnings, fresh starts, and setting intentions. It is a time to plant seeds and make plans for the future." As such, the New Moon is often associated with the start of a new relationship — or the start of a new chapter in an existing one.

Waxing Crescent

"This phase is associated with growth, expansion, and taking action on the intentions set during the New Moon." In terms of relationships, this can be a good time to focus on personal growth and self-development, which in turn impacts your relationship with yourself and others.

First Quarter

"This one represents a time of challenge and decision-making. It is a time to take action and overcome obstacles that may arise." Ergo, make decisions in terms of your sex life and connections during the First Quarter moon.

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Waxing Gibbous

"This phase is associated with refinement, focus, and attention to detail. It is a time to fine-tune plans and make adjustments as needed." Waxing Gibbous also represents strength and empowerment — focus on sexual confidence and assertiveness now.

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Full Moon

"This is a time of completion, manifestation, and illumination. It is a time to celebrate achievements and release anything that no longer serves." There may be increased energy and heightened emotions around the Full Moon, which can increase sexual desire.

Waning Gibbous

"This one is associated with gratitude, reflection, and preparation for release. It is a time to express gratitude for what has been achieved and prepare for what's to come." Given that we reflect during this time, now is a good time to think about your sexual experiences and desires.

Third Quarter

"This phase represents a time of release, letting go, and surrendering. It is a time to release what no longer serves and make space for new beginnings." Let go of your limiting beliefs about sex and relationships during this phase!

Waning Crescent

"This phase is associated with rest, renewal, and introspection. It is a time to reflect on the past lunar cycle and prepare for the next one." Focus on self-care (and maybe self-love, too).

Moon compatibility in astrology

A pattern Bell often notices with long-term couples is that one is born closer to a new moon (when the moon isn't visible with the naked eye), and another is born closer to a full moon. When looking at secondary progressions— a method of predictive astrology that "progresses" one's birth chart — having that pattern is great, Bell said. One partner may be in their progressed new moon stage, meaning they're in a quieter, more self-reflective period, while the other is in their progressed full moon phase, symbolizing a period of being more public and outward-facing. The current periods of their life balance each other out.

"In terms of astrology, the phase of the moon at the time of someone's birth can also be important in determining their emotional nature and inner world," Dettmann said. The birth moon phase can also offer insight into someone's emotional needs and patterns.

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As both Bell and Stardust assert, signs and elements (water, fire, air, and earth) of you and your partner's moons are important too. "If you have the same moon sign or a moon sign of the same element as your partner (both having water sign moons for example) it's easier to understand each other's emotions and intuit what each other is feeling," Bell said. Living together could come more naturally too as you understand each other's idiosyncrasies. 

Bell often sees couples that have moons in signs that are opposite to one another (meaning opposite on the birth chart wheel), i.e. one partner having a Cancer moon and the other a Capricorn moon. "It's like they subconsciously seek out qualities in the other person that they feel they may lack," she explained.

SEE ALSO: How to have the 'define the relationship' (DTR) chat

Then there's the house placements of the couple's moons. Everyone's birth chart contains 12 houses, each symbolizing a different aspect of your life and those around you. Bell said house placement is important, but you don't have to have your moon in the same house as your partner — you may be attracted to someone with other planetary placements there, though.

"For instance, if you have your moon in the 12th house, you may naturally be attracted to someone who has other planets (doesn't have to be the moon) in the 12th house in their own chart," Bell said.

Something else to consider is house overlays in a synastry chart (a combination of you and your partner's birth charts to determine compatibility). Bell most often sees that one partner's moon fall into the first, fourth, seventh, or tenth house of the other person's chart, or close to important angles like the ascendant (aka your rising sign), descendant (opposite of the ascendant), Midheaven (the highest point of the chart), and Imum Coeli (opposite of the Midheaven).  

"With someone's moon activating these parts of your chart, moon related themes like emotions, home life, and intimacy become more prominent in the relationship, and you may feel more comfortable sharing emotions with each other," Bell explained. 

For example, the fourth house symbolizes home and family. When your partner's moon falls in your fourth house, or vice versa, then transits to that sign (aka planets moving in that sign) will activate big changes in home or family for both of you at the same time, Bell said. "Home life and innermost emotions are associated with both the fourth house and the moon," she added.

Ultimately, know that there's a lot more to compatibility than the moon phase — and don't use TikTok to determine whether you and your boo are soulmates.