Expectant parents are usually preoccupied with speculating the gender of their baby ^[25], and this preoccupation has fueled the popularity of various gender prediction methods, from traditional beliefs to modern approaches.

However, like many expectant parents, you might approach these methods skeptically. It is normal to doubt the accuracy and reliability of all these different methods and wonder if they truly work for everyone or are simply based on chance.

In this article, you’ll learn about the history and how the Chinese Gender Predictor works, get insight into what science says about it, find answers to common concerns, and get practical tips if you’re curious about using this ancient method to predict your baby’s gender.

What Is the Chinese Gender Predictor Chart?

The Chinese Gender Predictor Chart is an ancient tool believed to predict and possibly influence your baby’s sex based on your age at conception and the month your baby was conceived, using the Chinese lunar calendar^[2].

This method works by converting your age at the time of conception and the month your baby was conceived into dates on the Chinese lunar calendar. Then, using a special chart, it predicts whether you’re having a boy or a girl based on that information^[3].

This chart is a traditional tool from the early Qing dynasty, drawing upon principles of an ancient Chinese book of divination (the I Ching), including Yin and Yang, the Five Elements, and the Eight Trigrams. The chart was believed to have been created between 1644 and 1912 and was found in an emperor's tomb in the last century, because ancient Chinese rulers placed a lot of importance on the birth of sons ^[1]. In traditional Chinese society, sons were often favoured due to their roles in continuing the family lineage, performing ancestral rites, and supporting parents in old age.

Beyond mere prediction, these charts have also served a broader purpose historically, helping families understand and perhaps even avoid sex chromosome-related diseases through early family planning^[1].

How Our Chinese Gender Predictor Tracker Works?

To use our Chinese Gender Predictor Tracker to estimate your baby's gender, you need two key pieces of information: your age and the month you conceived. Our tracker operates on the principles of the traditional Chinese lunar calendar, a system different from the common Gregorian calendar (modern calendar used worldwide).

Unlike the Gregorian calendar, which is a solar calendar, the Chinese lunar calendar follows the moon's cycles. It consists of 12 lunar months, each beginning on a new moon, with each month typically lasting about 29 to 30 days. This results in a lunar year slightly shorter than the solar year, leading to adding a “leap month” every few years to realign the calendar with the seasons. 

The unique arrangement is believed to influence various biological phenomena like the human circadian rhythm (the natural, internal process that regulates the sleep-wake cycle) ^[4] and may even influence the gender of a baby.

Our tracker converts these dates to their lunar equivalents to provide the most accurate predictions possible. This step is important, as a person’s lunar age is typically one to two years older than their actual age ^[5], depending on their birthdate and the timing of the Chinese New Year.

How Accurate Is The Chinese Gender Predictor Chart?

While the Chinese Gender Predictor Chart is widely used due to its strong connections with Chinese mythology, its accuracy has been widely debated. A significant study on the accuracy of the Chinese gender predictor chart is an analysis led by Professor Villamor Eduardo. This large-scale study reviewed data from nearly three million singleton births in Sweden between 1973 and 2006, using an algorithm to estimate each mother's lunar age and conception month based on the Chinese lunar calendar. 

The researchers calculated the kappa statistic and found it to be 0.0002. In practical terms, this means the chart's predictions were correct in roughly 50% of cases, aligning with the probability of random guessing, as there are only two possible outcomes of the sex of a baby (male or female). This finding concluded that the Chinese lunar calendar method lacks a biological basis and is unlikely to offer accurate predictions beyond simple chance ^[6].

Some parents who use the Chinese Predictor Chart report accurate predictions, while others do not, suggesting that any correct predictions may be coincidental rather than indicative of the method's reliability. Below are some more accurate tools for predicting your baby's sex.

Ultrasound scans

Medical tools like ultrasound scans have an accuracy rate of 87% to 99%, which is relatively higher than the 50% of the Chinese lunar method. The probability of accuracy is significantly higher as the gestational age increases from the first to the second trimester ^{[7] [13]}. Therefore, it is advisable to wait until the second or third trimester of your pregnancy to get accurate results.

Non-invasive prenatal testing (NIPT)

Non-invasive prenatal Testing is another tool for accurately predicting your baby's gender. It is primarily designed to screen for chromosomal abnormalities and is conducted as early as 10 weeks of pregnancy ^{[8] [14]}. It is very accurate for sex determination because it reliably screens for sex chromosomes and differences in the usual number of chromosomes, making it a powerful tool ^[9].

Chorionic Villus Sampling (CVS)

Chorionic villus sampling and amniocentesis are invasive diagnostic procedures performed between 10 and 13 weeks of gestation and 15 and 20 weeks or later, respectively ^{[17] [18]}. These tests provide accuracy in determining sex because they also scan for chromosomes, including looking at the sex chromosomes ^[22]. However, due to the small but significant risk of miscarriage associated with these procedures, they are typically reserved for pregnancies with specific medical indications such as an increased risk of aneuploidy, a condition where fetal cells have an abnormal number of chromosomes, leading to genetic disorders like Down syndrome, Turner syndrome and Klinefelter syndrome ^[27].

Amniocentesis

Amniocentesis detects a baby’s sex by analyzing fetal cells found in the amniotic fluid, which is collected through a small needle inserted into the uterus between 15 to 20 weeks of pregnancy. These cells contain the baby’s DNA, allowing doctors to determine the baby’s genetic sex with high accuracy through genetic testing ^[16].

Preimplantation Genetic Testing (PGT)

Preimplantation Genetic Testing (PGT) is used during in vitro fertilization (IVF) to examine embryos for genetic conditions and chromosomal sex before implantation. This allows doctors to identify the sex of each embryo, along with any genetic abnormalities, ensuring only healthy embryos are selected for transfer^[15].

Does the Chinese Gender Predictor Predict Gender or Sex?

The Chinese Gender Chart, despite its name, attempts to predict biological sex, not gender. Its prediction is based on physical attributes rather than personal identity. ^[11].

Gender and sex are often used interchangeably, but have different meanings ^[10]. Recently, our understanding of gender and sex has evolved significantly, reflecting broader social, cultural, and scientific development. 

Biological sex refers to the physical characteristics you’re born with, like chromosomes, genes, hormones, and body parts, and is usually categorized as male or female, though there are natural variations (such as being intersex, where a person is born with reproductive or sexual anatomy that doesn’t fit typical definitions of male or female) ^{[10] [28]}. Gender identity is your personal, internal sense of being male, female, both, neither, or somewhere else, and it might be different from the sex you were assigned at birth^{[11] [12]}.

In summary, this calculator provides an estimate of your baby’s biological sex based on traditional lunar calendar methods, but it does not predict gender identity.

What Parents Say About the Chinese Gender Predictor Chart

“I use it to predict, it's right for my first son and not right for my second son”, a parent said in a Chinese astrological forum ^[30]. 

Many parents consult the Chinese Gender Predictor Chart, data from a study conducted in Massachusetts General Hospital (MGH) found that the number of male and female newborns was nearly equal, with a few ambiguous cases excluded from the analysis. This showed that accurate prediction of fetal gender based on the Chinese birth calendar was no better than a coin toss, as gender prediction based on maternal age calculated using the Chinese lunar calendar gave a 50.2% accuracy ^[23].

Parents in different forums have also been seen comparing results and celebrating when the chart gets it right. But it seems more like a coincidence than science. While it is exciting to use, there is no medical backing for the Chinese lunar chart, and you might want to take it with a grain of salt.

You should explore more accurate baby sex prediction methods like ultrasound ^[24], non-invasive prenatal testing, chorionic villus sampling, and amniocentesis. These methods can also help to spot chromosomal irregularities early on.