Pregnancy Symptoms—Week 3 (Still Waiting to Feel Pregnant)
At three weeks pregnant, you still may not feel any early pregnancy symptoms at all. And because it’s still so early, you won’t be able to test for pregnancy yet. Hang on one more week until your first missed period. If you conceived this cycle, then the egg was most likely fertilized in the past few days. Ovulation usually occurs around cycle day 14. But this is an average, and the exact ovulation date varies from woman to woman. (One study found that women ovulated anywhere from cycle day 8 cycle day 26.)
So, since pregnancy is counted from the first day of your last menstrual period, it’s hard to determine at this point whether the egg has been fertilized yet or not. But either way, you’re getting close to the moment of conception.
What happens after conception?
When you’re trying to determine when your pregnancy began, the date you’re really looking for is implantation—when the fertilized egg burrowed into your uterine lining, thereby beginning your pregnancy. You can figure out this date using a couple of simple formulas (which we’ve also covered in our implantation calculator post).
The process of implantation usually takes place between eight – 10 days after ovulation. And as soon as it is complete, the embryo starts producing hCG, which is the hormone that pregnancy tests detect.
Are there any pregnancy symptoms in week 3?
Probably not. In a non-pregnancy cycle, progesterone levels would be falling at this point. But in pregnancy, hCG sends a signal for progesterone production to continue, and to increase. This increase in progesterone levels is responsible for many of the first signs of pregnancy. But at this point, you probably won’t be feeling anything just yet.
Well, when will I feel pregnant?
Most women begin to feel symptoms around the fifth or sixth week. This study, which examined 136 women for the onset of pregnancy symptoms, found that half of the women felt symptoms by the end of the fifth week and 89% did so by the end of the eighth week.
How big is the baby?
Baby’s Length: 0.0 in.
Baby’s Weight: 0.00 oz.
How is the baby developing?
Once the sperm and egg meet, they create a single-cell, fertilized egg called a zygote. Almost immediately, this cell will divide as it makes its way through the fallopian tube toward the uterus. Eventually, the zygote becomes a hollow ball of cells called a blastocyst.
This may surprise you, but your child’s sex and inherited genetic characteristics (like hair, eye, and skin color; body type; and even some personality and intelligence traits) are set at the moment of conception. Your zygote has 46 chromosomes—23 from you, 23 from your partner. These chromosomes are the blueprint your baby follows as it develops.
What about multiples?
If more than one egg is released during ovulation and each is fertilized by a sperm, more than one embryo may implant and grow in your uterus; this results in fraternal multiples. When a single fertilized egg splits, it results in multiple identical embryos. Identical multiples are less common than fraternal ones. Your likelihood of having multiples increases if there’s a family history of multiples on your side, if you’re taking fertility drugs, or if you’re older than 35. Also—if you’ve already delivered fraternal multiples, you’re five times more likely to carry another set in your next pregnancy.
What’s happening in my body?
Implantation usually occurs 8 – 10 days after ovulation. It takes this long for the fertilized egg to make its way through the fallopian tube and into the uterus. Once there, the blastocyst buries itself—or implants—into the uterine wall.
Once implantation occurs, your body releases hCG, signaling your ovaries to stop releasing additional eggs. HCG is the hormone that pregnancy tests—both blood and urine—detect. (For more information on your hormones, check out our post, Hormones 101.) Hold off on taking that pregnancy test, though. It takes time for hCG to build up in your system, and it’s recommended to wait until 12-14 days after ovulation to take a pregnancy test. (Otherwise, you could quite literally be flushing money down the toilet.)
Many women wonder if they will feel implantation symptoms. But since the symptoms of implantation and early pregnancy can mimic the same symptoms a woman has as progesterone rises in the weeks leading up to her period, it’s nearly impossible to distinguish the difference.
The waiting game
Waiting for a missed period or a positive pregnancy test can be tough. It’s completely normal to analyze every little ache and twinge, wondering if they’re a sign of pregnancy. (Here, we offer 17 Ways to Survive the Two Week Wait.)
In some cases, like if you’re at risk for an ectopic pregnancy or miscarriage, your doctor may bring you in for a blood draw. Pregnancy blood tests are more sensitive than urine tests, which means they’re able to detect far smaller amounts of hCG.
Even though it’s a little early, in some cases you may begin experiencing some of the first signs of pregnancy. If your cycle is typically shorter than 28 days, by the end of the week, you may realize that you could be pregnant.
Will my pregnancy be O.K.?
It’s very common and completely normal to worry about miscarriage and the safety of your pregnancy. About 15% of clinical pregnancies miscarry. A clinical pregnancy is one that is confirmed by high levels of hCG (the pregnancy hormone) as well as ultrasound which will detect the gestational sac or heartbeat. But when you consider pre-clinical losses as well, the actual incidence of miscarriage is closer to 50%, making it by far the most common complication of pregnancy. So, if you do lose a pregnancy, know that you are not alone. (Also remember: it is not your fault.)
Although losses do happen, and researchers are still learning about the causes of miscarriage, in most cases there is nothing that could have been done to prevent them. Most of the time, pregnancy losses are caused by chromosomal abnormalities, meaning that the embryo wasn’t viable.
How does my immune system know not to attack the embryo?
For a long time, researchers have wondered why a mother’s immune system doesn’t reject a developing fetus—with its different antigens—as foreign tissue. According to research, the implantation of an embryo changes the packaging of specific relevant cells that form the decidua—the specialized structure that encases the placenta and the fetus. Because of these changes, the body’s immune system ignores the decidua, reading it as a zone of immunological inactivity. (Pretty amazing how smart the body is, isn’t it?)
And studies—like this one published in the journal Scientific Reports—have shown that the lining of the uterus also sets something akin to an entrance exam for embryos. In other words, the body is trying to detect whether or not the embryo is viable.
Sometimes, eggs will become fertilized, but they don’t implant in the uterus. Often, these embryos contain abnormal cells or chromosomal errors. Ideally, the “entrance exam” checks the health of an embryo. And when it is functioning correctly, the uterus allows only high-quality embryos to implant— preventing pregnancy loss, fetal growth restriction, or preterm birth.
What else should I do this week?
- Go out with your partner or friends and have some fun—anything to distract yourself from the waiting! At this point, though, it’s important to avoid drinking too much alcohol.
- Get plenty of sleep, some gentle exercise, and eat a healthy, balanced diet.
- If you haven’t already, you should absolutely stop smoking or taking any recreational or illegal drugs.
- Continue taking your prenatal vitamins with folate; this period of early development is when it’s most important to have adequate folate in your system. Even before you realize you’re pregnant, your baby’s busy growing. One of the first things to form is the neural tube. Adequate folate helps prevent neural tube defects, like spina bifida and anencephaly, which can be severely debilitating or fatal.
- Read up on the first trimester. Pretty soon, you’ll be getting that positive pregnancy test!
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