By 3 weeks pregnant, you are closing in on ovulation or you've already ovulated. During the first two weeks of your menstrual cycle, your body is preparing to get pregnant.
While you were having your period two weeks ago, your ovaries were developing between 15 and 20 follicles (each carrying an egg cell). Both ovaries contribute to helping these follicles grow, but usually only one follicle (one egg) will mature. When your egg is mature, it will burst from the follicle and swim to your fallopian tube, where it stays for roughly 24-36 hours.
Though most women will release one egg during ovulation, it is possible that more than one egg will be released. If you release two eggs and they are fertilized, you will get fraternal (or non-identical) twins.
A Sperm's Journey
During 3 weeks pregnant, you may mistakenly believe that you must have sex on the day of ovulation to conceive. This is not so, as it can take sperm several days to reach the awaiting egg. Fast swimming sperm can reach the egg within half an hour, while slow swimmers may take days. As a result, many doctors suggest that you have sex every 24 to 48 hours during the week of ovulation to improve your chance of becoming pregnant. This will maximize the chance of your partner's sperm making it to your fallopian tube before the egg leaves.
Out of the 250 million sperm released at ejaculation, only about 200-300 sperm will actually reach your egg. This is due to the natural barriers and hurdles that exist in your reproductive system.
Beginning of Conception
When the sperm reaches your egg, they will cluster around it, working hard to penetrate its outer layer. Only one lucky sperm will manage to burrow its way inside your egg. When this happens, the egg's outer layer will thicken to keep out competing sperm. At this point, conception occurs.
When the sperm and egg finally meet, they form a "zygote," a single cell that starts to divide as it travels down through the fallopian tube. Pretty soon, the zygote forms into a compact cluster of cells, called a "blastocyst." The blastocyst works hard to attach itself to your uterine lining.
Your future baby's sex has already been determined at this point, even if your little one is only a ball of cells now.
As the blastocyst implants itself in the lining of your uterus, you may experience implantation bleeding - light bleeding that looks like a very light period. Women often confuse this with the start of their menstrual cycle.
Human Chorionic Gonadotropin (hCG)
Following conception, your body will switch off your menstrual cycle by producing a hormone called human chorionic gonadotropin (hCG). This hormone helps your body maintain high levels of the hormone progesterone, which helps support your pregnancy. With these hormonal changes, it's not uncommon for you to start experiencing some early signs of pregnancy.
Early signs of pregnancy include:
Breast tenderness
Fatigue
Bloating
Pain on one side of the abdomen (ovary)
Cramping
Increased appetite
Metallic taste in your mouth
Increased need to relieve your bladder
Because many of these early pregnancy symptoms are similar to the ones that you experience during PMS, pregnancy week 3 is often too early to know whether you have conceived. That's why it's important to continue to eat healthy and avoid bad habits, such as smoking or drinking.
How to Promote Conception
To promote conception, you can also spend time in bed imagination the process. Visualization is a powerful technique that you can use to increase your odds of becoming pregnant. It also inspires much hope and helps you relax rather than dwellon whether or not you are pregnant!
Don't get stressed if you haven't conceived yet. For 75 percent of couples, it can take upwards of six months before they have success.
Fertility and Age
Fertility also declines with age. Women are at their most fertile between ages 20 and 24. Fertility gradually declines in the 30s and 40s, though women in this age group still get pregnant!
Your risk for chromosomal abnormalities and miscarriages also increase as you age.
Men also face fertility problems as they get older. Although men can produce sperm well into their 80s, they also have a biological clock of sorts. As men age, it may take them longer to get their partners pregnant. The quality of sperm also decreases. The sperm of older men is more likely to contain damaged DNA.
If you are an older dad or mom (over age 35), don't worry! You can still increase your risk of having a healthy baby by living a healthy lifestyle.
Twin Fetal Development
At 3 weeks pregnant, you may be curious about twin pregnancy. Though you will not know whether you are carrying twins or a singleton until your first prenatal visit at pregnancy week 8, it is fun to think about this idea. At this early week of pregnancy, you may already be carrying twins and not know it!
There are two types of twin pairs: fraternal and identical.
Fraternal Twins
Fraternal twins (also called non-identical twins) occur when two eggs are released during ovulation and they are fertilized. Each twin gets his or her genes from the parents, but the twins will not share the same genetic material. Non-identical twins are no more alike than other siblings, and they can be two different genders. Sometimes, fraternal twins can look very similar and it can be difficult to tell them apart, especially if they are the same gender.
Identical Twins
In the case of identical twins, they develop after a fertilized egg splits into two fetuses. Identical twins are always the same sex, and they share the same genes. This type of twin set is less common than fraternal twins.
Identical twins can share the same placenta, and they can sometimes share the same amniotic sac. Fraternal twins have their own placenta and amniotic sac.
Twin Statistics
Twin births have increased by 70 percent in the last 30 years. This may be due to more women delaying pregnancy until later in life and more women undergoing infertility treatments.
You are more at risk for carrying twins if:
You have a family history of twins or multiple births. Heredity plays a role in multiple pregnancies.
Women of African descent are more prone to multiple pregnancies than other races.
You have had a multiple pregnancy in the past. This increases your risk of having another one
You are over 35 years of age.
Twin births occur in one out of every 32 births. Identical twins only occur in one of every 100 births.
Sometimes when you are carrying two babies, you may face extreme bouts of morning sickness (nausea and vomiting). You can sometimes feel more fetal movement than in previous pregnancies. Your belly and uterus will also grow faster or larger than expected.
With a multiple pregnancy, you have an increased risk of certain pregnancy complications, including pre-term labor, high blood pressure, anemia, premature rupture of membranes, and fetal growth problems. You may also need a cesarean section.
When you are pregnant with twins, you will need extra calories and nutrients than a regular pregnant person. You will need to get more calcium and folic acid in your diet. Talk to your doctor about your dietary concerns.
If you have twins in your family, you want to start toying with the idea that you could possibly carry twins now at 3 weeks pregnant. Raising twins can be lots of fun!
Vanishing Twin Syndrome Sometimes a pregnancy can start out with twins, but you have a very early miscarriage. Often occurring in the first trimester, this phenomenon is called "vanishing twin syndrome." The incidence of this strange syndromeis higher than you might think - some estimate that the rate is as high as 30 percent in all multiple pregnancies.
In some cases of vanishing twin, the pregnant woman never knows she was expecting two. Before ultrasound technology, doctors were not aware of this phenomenon.
In other cases, an ultrasound indicates that you're carrying two babies with two heartbeats. You may be overjoyed with this news, but then your hopes are crushed several weeks later, when only heartbeat can be detected.
When vanishing twin occurs in the first trimester, you may not have any symptoms at all. You may experience some cramping or light spotting, but that's it. Without ultrasound, you would have never known!
Often, the miscarried twin had a chromosomal abnormality that caused its death. In most cases, the surviving twin is healthy and will be fine. Research indicates that older moms (over 35) are at higher risk for vanishing twin syndrome.
As you progress through your pregnancy week by week, try not to worry about miscarriage or vanishing twin syndrome. Chances are you will have a healthy baby, if you eat right and abstain from unhealthy habits.
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