The question of whether the new addition to the family will be a boy or a girl is one of the most exciting and emotionally significant moments for future parents. Knowing this helps not only to prepare for the arrival of the baby on a practical level, but also to establish a deeper emotional connection with the child even before birth. Modern medicine offers several reliable ways to lift this veil of mystery, including specific medical scenarios such as determining the sex of a future child after IVF. Today, you can find out the sex of your baby either through ultrasound imaging or through a highly accurate laboratory analysis of the mother’s blood—a non-invasive prenatal test (NIPT).
At what stage does the sex become known?
The earliest and most high-tech method of sex determination today is considered to be NIPT (non-invasive prenatal testing). This test can be performed as early as 9 weeks of pregnancy. The technology is based on the isolation and analysis of fragments of extracellular fetal DNA that enter the mother’s bloodstream through the placenta. It is important to understand that the primary purpose of this test is not simply to satisfy the curiosity of parents, but to screen for serious genetic abnormalities.
Nevertheless, the analysis allows the presence or absence of the Y chromosome to be determined with an accuracy of over 99%. If it is detected, it will be a boy; if not, it will be a girl. This test becomes critically important in cases where there is a family history of sex-linked hereditary diseases (e.g., hemophilia). Doctors often refer women for NIPT to rule out pathologies such as Down syndrome, Edwards syndrome, Patau syndrome, and other chromosomal abnormalities at an early stage, giving parents peace of mind in the earliest stages.
Determining sex using ultrasound diagnostics
Ultrasound examination is a classic, completely safe, and most affordable method of monitoring. An experienced doctor can make the first scientifically based assumption about the sex of the child as early as the 11th week of pregnancy during the first screening. During this period, the ultrasound specialist carefully examines the “genital tubercle” — the beginning of the future external genital organs. A preliminary prediction is made based on the angle of this tubercle relative to the fetus’s spine (sagittal sign).
However, the accuracy of the visualization directly depends on the timing and quality of the equipment:
- 16th week: Considered the “gold standard” for determining sex. At this stage, the external sexual characteristics are already sufficiently differentiated, and the probability of error is minimal with good visibility.
- 30th week: By this time, the testicles in boys usually complete the process of descending into the scrotum. This makes ultrasound diagnostics virtually indisputable, as the doctor can see clear anatomical structures.
Schedule of routine ultrasounds during pregnancy
Throughout the entire period of waiting for the baby, the expectant mother undergoes three key ultrasound screenings, each of which has its own objectives:
- First ultrasound (10–11 weeks): The main goal is to confirm the viability of the fetus and rule out major malformations. Determining the sex at this stage is probabilistic due to the microscopic size of the organs.
- Second ultrasound (19–21 weeks): This is the most detailed morphological analysis. The doctor checks the development of each organ, including the heart, kidneys, and brain. It is during this period that the sex of the child is most clearly visible, unless the baby is in an awkward position for examination (for example, with its legs tightly pressed together or turned away from the mother’s spine).
- Third ultrasound (32–34 weeks): In the later stages, the focus shifts to assessing the baby’s weight, the condition of the placenta, and blood flow. Determining the sex here serves as final confirmation of previously obtained data.
It is important to understand that many factors affect visibility during an ultrasound: the amount of amniotic fluid, the thickness of the mother’s abdominal wall, and, of course, the activity of the little patient.
Features of sex determination in IVF
A pregnancy resulting from in vitro fertilization (IVF) requires special attention from specialists. For couples who have gone through this process, each stage of diagnosis carries an increased emotional burden. In this case, ultrasound and NIPT methods also remain the main ones, but the interpretation of the results may have its own nuances.
For example, in multiple pregnancies after the transfer of several embryos, the accuracy of NIPT in determining the sex of each child may be lower. In situations involving donor eggs or dual donor programs (eggs and sperm), the timing of the tests remains standard, but doctors take extra care when performing expert ultrasounds in the second trimester to ensure that the information provided to parents is completely reliable.
Where can you get high-quality diagnostics?
To obtain the most accurate results and eliminate the human factor, it is extremely important to use high-resolution, expert-grade equipment. At the Natuvitro reproductive medicine clinic, expectant mothers can undergo all the necessary tests in a comfortable environment under the supervision of highly qualified obstetricians and gynecologists.
The clinic has innovative equipment for performing 3D and 4D ultrasounds. Unlike conventional two-dimensional images, these technologies allow you to see a three-dimensional picture and even the baby’s facial expressions in real time. As a memorable gift, patients receive a video recording of the examination—a unique chronicle that will become the first chapter in the family video archive and will allow you to preserve the touching moments of anticipation.
Thanks to the synergy of doctors’ experience and modern technological advances, today’s parents can find out the sex of their baby early on, while remaining fully confident in the safety and medical accuracy of each procedure.
Frequently Asked Questions (FAQ)
1. Can the results of the first screening ultrasound be trusted 100%? Unfortunately, no. The accuracy at 10-11 weeks varies between 60-70%. Since the genitals of boys and girls look almost identical at this stage (like a small protrusion), there is a risk of error due to an unfavorable angle. Doctors recommend making a final and reliable conclusion in the second trimester, starting at 16-18 weeks.
2. Is the NIPT test safe for the mother and baby? This method is considered completely safe (non-invasive). Unlike amniocentesis, NIPT only requires a routine blood sample from the mother’s vein. The procedure does not pose any risks to the pregnancy, does not cause uterine contractions, and does not come into contact with the baby in any way.
3. Why is it that sometimes the doctor can’t determine the sex during the second ultrasound? The most common reason is that the baby is “shy.” If the fetus is in a breech position, has its legs crossed, or is turned away from the sensor, the genitals may simply be hidden from the doctor’s view. Umbilical cord loops can also be an obstacle. In such situations, a repeat examination is usually scheduled in 7-10 days, when the baby will have changed position.
4. Can NIPT be wrong in determining gender? The probability of error is extremely low – less than 1%. False results may be associated with very low levels of fetal DNA in the mother’s blood (which occurs with early testing or high maternal BMI), as well as, in rare cases, chromosomal abnormalities. An error is also possible if there was initially a multiple pregnancy, but one of the embryos stopped developing.
5. Does the mother’s excess weight affect the accuracy of the ultrasound? Yes, excess subcutaneous fat on the abdomen can interfere with the passage of ultrasound waves. This creates so-called “acoustic noise,” which makes the image less clear. In such cases, doctors advise waiting until 20-22 weeks, when the organs become larger and easier to identify even with impaired visibility.