If you're pregnant at 4 DPO, a sperm cell fertilized one of the eggs that was released 4 days ago. This process usually happens inside your fallopian tubes. Once the egg and the sperm cell merge during fertilization, these two cells will transform into a zygote.
The zygote travels down the fallopian tube to reach the uterine cavity. At the same time, the zygote will start to divide itself into multiple cells. These cells are "totipotent," which means that they can turn into any of the cells that make up the human body.
Approximately 4 days after fertilization, the zygote will have divided into 16 totipotent cells. From this point on, the zygote is known as a morula. The morula will keep on dividing and developing until it becomes a blastocyst and, later, an embryo. At 4 DPO, the fertilized egg has become either a morula or a blastocyst.
Once the egg is fertilized, your body receives signals to start releasing hormones, such as human chorionic gonadotropin and progesterone, that will be vital to maintaining a healthy pregnancy.
If you're actively trying to conceive, it's normal to be extra aware of any pregnancy symptoms that you might be experiencing. This is especially true if you took an ovulation test and know for sure when ovulation occurred. While some women do experience mild symptoms at 4 DPO, it's much more likely that you'll have to wait a bit longer to feel pregnant.
Some women experience mild abdominal cramps during the early days of pregnancy. However, this can a confusing symptom, since it could also signal that your period is about to start. While it's not impossible that cramping at 4 DPO is a result of pregnancy, it's also not extremely likely.
Some women experience very light cramps on one side of their abdomen when they ovulate. You might have experienced light cramping a few days ago that signaled your ovulation.
Spotting in early pregnancy is frequently caused by implantation. Implantation bleeding usually occurs about 6 to 12 days after the egg is fertilized. This means that spotting at 4 DPO isn't likely to be caused by implantation bleeding. It's still too soon for implantation to be complete.
If you did conceive this month, you could experience implantation bleeding during the next few days. Not all pregnant women experience implantation bleeding, though. In some cases, the bleeding is so light that women simply never notice it.
Nausea is one of the earliest pregnancy symptoms for most women. However, research shows that only 10 percent of pregnant women experience nausea before they miss their period. If you haven't experienced nausea at 4 DPO, don't worry. It's perfectly normal if you don't "feel pregnant" at this stage. Very soon, your hormone levels will rise, leading to pregnancy symptoms.
Other very early pregnancy symptoms can include:
- Sore breasts
- Nasal congestion
- Frequent urination
- Mood swings
- Food aversions
It's important to keep in mind that few women experience any symptoms at 4 DPO. It's far more common not to notice any symptoms at this point. Symptoms that you do experience could be related to a different cause, such as a cold or impending period.
When you're at 4 DPO, the fertilized egg could still be traveling down your uterine cavity. During implantation, the fertilized egg will burrow itself into your uterine lining. The uterine lining is thick and will provide the nutrients that your baby needs to grow until the placenta is formed.
Implantation itself usually occurs between 6 and 12 DPO. Therefore, it's unlikely that you'll experience a complete implantation at 4 DPO. But the fertilized egg might have already reached the uterine cavity, which is where implantation will begin soon.
The fertilized egg can spend up to 72 hours inside the uterine cavity before implantation. During this period, your uterus will secrete nutrients and hormones to nourish the embryoblast (a mass of cells from which the embryo forms). At the same time, hormonal changes are preparing your uterine lining for a successful implantation.
To get a positive pregnancy test result, the human chorionic gonadotropin hormone (hCG, also known as the pregnancy hormone) needs to be high enough to be detected by a pregnancy test. The placenta will only start to release this hormone after the egg has implanted into your uterine lining.
It's highly unlikely for the fertilized egg to have completed implantation at 4 DPO, so you probably won't be getting a big fat positive test result just yet. It's normal to want to find out if you're pregnant as soon as possible, but experts recommend waiting at least until the first day of a missed period to take a pregnancy test.
Taking a home pregnancy test so soon after ovulation will probably result in a negative test, even if you are indeed pregnant. To keep this from happening, wait until you miss your period before you take a pregnancy test. By then, your hCG will probably be high enough to be detected.
4 DPO is still very early in your pregnancy, but there are many exciting things happening inside your body already. The fertilized egg is already developing and preparing for the long journey ahead. It's still too soon to take a pregnancy test, so try to be patient. In a few weeks, you'll be able to confirm whether or not you're pregnant.