Fertilization Of Your Eggs
Your egg travels down your fallopian tube , waiting for a single sperm to fertilize it.
The lucky sperm makes its way into the fallopian tube and burrows into the egg, fertilizing it. Once fertilized, the egg changes its lining to prevent other sperm from entering the egg.
Instantly upon fertilization, your babys sex and genes are determined.
The sperm decides whether the baby will be a boy or a girl: if the sperm has a Y chromosome, your baby will be a boy while if it carries an X chromosome, your baby will be a girl.
So, if you were hoping for different sex, talk to the father!
Once fertilized, the egg starts to divide from one cell to many cells.
It continues to divide as it moves slowly from the fallopian tube into the uterus, where it is looking for a home. Below is a microscopic image of the egg roughly 24 hours after fertilization.
Why Your Due Date Is Important
Your due date is likely one of the first bits of information youll seek out after you find out youre pregnant. Friends and family will want to know so they can look forward to greeting your new baby .
Doctors, midwives, and nurses will want to know so they can track important health milestones and make decisions about interventions and prenatal testing.
Your due date is less of a deadline and more like a time marker. Your due date indicates the 40th week since your last menstrual period or the 38th week from ovulation.
Once your due date is calculated, you’re likely to give birth within a four-week period that surrounds your due date. In other words, sometime during the two weeks prior to and two weeks after your assigned due date, you’ll likely meet your baby.
Around 70 out of every 100 pregnant people will have their baby within 10 days of their due date. Assuming there are no complications, others will deliver either a little earlier or a little later than that.
The due date is valuable for many reasons, including the preparation of your home and family for the new arrival. There are also several other reasons it’s helpful to know your due date.
Calculate Using Your Last Menstrual Period
The formula for calculating how far along you are is simply the number of days since the first day of your last menstrual period divided by seven:
Days since start of LMP ÷ 7 = # of weeks pregnant
Wondering how to calculate your number of months pregnant?
Days since start of LMP ÷ 30 = # of months pregnant
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Pregnancy Week 4 Fetal Development
During this important phase of your pregnancy, the embryo grows and develops within the lining of the uterus. The outer cells form links with your blood supply, while the inner cells form 3 separate layers:
- The inner layer becomes the lungs, stomach, gastrointestinal system, and bladder.
- The middle layer becomes the heart, blood vessels, muscles, and bones.
- The outer layer becomes the brain and nervous system .
During the first part of this stage of pregnancy, the embryo draws nourishment from a small yolk sac. Soon afterwards, the placenta that develops from the outer layer of the amniotic sac that surrounds the embryo takes over this role of providing sustenance to your growing baby.
During this period, the beginning of a face starts to form: this includes large, dark circles for eyes, and a mouth, lower jaw, and throat. Blood cells start to form and the circulation begins.
What Does It Mean If My Doctor Changes My Due Date
Your doctor may change your due date if your fetus is significantly smaller or larger than the average fetus at your particular stage of pregnancy.
Generally, your doctor orders an ultrasound to determine the gestational age of your baby when theres a history of irregular periods, when the date of your LMP is uncertain, or when conception occurred despite oral contraceptive use.
An ultrasound allows your doctor to measure the crown-rump length the length of the fetus from one end to the other.
During the first trimester, this measurement provides the most accurate estimation for the age of the baby. Your doctor may change your due date based on the ultrasound measurement.
This is most likely to occur in the first trimester, especially if the date estimated by the ultrasound differs by more than one week from the date estimated by your doctor based on your LMP.
In the second trimester, an ultrasound is less accurate and your doctor probably wont adjust your date unless the estimates vary by more than two weeks.
The third trimester is the least accurate time to date a pregnancy. Estimates based on an ultrasound can be off by as much as three weeks, so doctors rarely adjust dates during the third trimester.
However, its not uncommon for a doctor to perform an ultrasound in the third trimester if theyre thinking about changing your date.
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Determining If Labor Is Premature
Babies who are born too early are at risk for numerous health problems. There are steps we can take to slow or halt preterm labor. With that said, there are also risks to the medications used to stop preterm labor, both to the mother and the baby.
You and your doctor have to decide together when the risks of allowing labor to continue to outweigh the risks of intervention. This is partially determined by knowing which week of pregnancy you are in.
There are also risks to the baby and mother if a pregnancy goes on for too long. Post-term pregnancy is when birth does not occur by week 42 . If this happens, your midwife or doctor may decide to induce labor.
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Sex At Week 37 Of Pregnancy
Sex at 37 weeks is perfectly fine for most pregnancies. Unless told otherwise by your doctor, you and your partner can continue to be intimate until your water breaks or youre rushing to the hospital due to real labor contractions.
Youll definitely want to experiment with different positions if your go-to is missionary. For example spooning . At 37 weeks, there can be too much pressure on your belly. Also, it isnt a good idea to lie flat on your back for too long because it can compromise blood flow to the large blood vessels behind the uterus.
Another thing you may experience after having sex at 37 weeks is spotting. Your cervix is very tender now, and theres a lot more blood flow in that area than usual, so you may get irritated pretty quickly. A little blood is usually not a cause for concern.
Feeling antsy? Week 37 is the perfect time to prepare mentally and physically for babys arrival. Here are some things you can do each day of week 37 to better prepare yourself for D-day.
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Calculator: Is My Menstrual Period Late
Is your period late or could you be pregnant? Use this menstrual period calculator to see if your period is late or if a baby may be the way!
Missing a period, especially if you always had regular menstrual periods, is a significant event, so naturally, the next question that follows is, “Am I pregnant?” Pregnant women have no menstrual period. But not every woman who misses her period is pregnant.
Factors Affecting Due Date
With so much focus and excitement over an assigned day, youd think itd be an accurate numberbut its not always the case. The simple truth is that only 5 out of 100 women will deliver their babies on their actual due date.
Still, determining which week of pregnancy youre in is crucial to receiving good prenatal care and planning for your upcoming life change.
The majority of babies are born over a 35-day span, with birth occurring anywhere from about 37.5 weeks to 42.5 weeks. Due dates also not deadlines. You could have your baby a week later than your due date and still be considered on time.
There are many factors that can influence your due date.
- Each pregnant person has their own predetermined schedule. Many people will tell you that their pregnancies were all about the same length. If you had two kids, each delivered around 41 weeks, your third kid is likely to arrive around 41 weeks.
- People pregnant for the first time tend to go into labor later. Youre more likely to go a few days past your due date with your first baby.
- Some people are at risk of preterm labor. About one in 10 pregnancies end with premature delivery. Maternal risk factors for prematurity babies include having a previous preterm birth, vaginal bleeding during pregnancy, diabetes, high blood pressure, smoking, and even periodontal disease.
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# First Ob / Midwife Visit How Soon After I Find Out Im Pregnant Should I See The Ob
Remember to take care of yourself during your pregnancy.
Take your vitamins, eat well and drink a lot of fluid. And get ready to schedule your OB appointment. Most women, if having a typical pregnancy, wont see their OB until their 9th or 10th week.
Great overview for prenatal tests here.
Some women may need to be seen earlier by their doctor if they have a positive pregnancy test and a recent loss, or if they need blood thinning medication or progesterone support.
If you havent already, start searching for an OB or midwife, and ask them when they want you to schedule.
What To Ask My OB At My First Appointment?
Below is an image from whattoexpect.com that reveals a list of questions for you to take to your OB.
Dating Pregnancy Using Ultrasound
Ultrasound in the first trimester is the most accurate method of dating pregnancy. During the scan, baby is measured and the age of pregnancy is estimated by comparing baby’s size against recorded averages. If there is a significant difference between gestational age according to LMP and gestational age according to the ultrasound, you may be given a new gestational age and due date based on the ultrasound measurements.
Your pregnancy may also be dated by ultrasound measurement if an LMP formula was not appropriate for your pregnancy for any reason. LMP formulas are not suitable in several situations including the following: LMP is not known or is not certain, birth control pills were taken in the two months before LMP, the menstrual cycle is irregular, you are carrying multiples .
Although the age of pregnancy based on ultrasound measurements is more accurate than the age of pregnancy based on LMP, both are estimates and not definitive statements.
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Your Body At Week 3 Of Pregnancy
Its very early days in your pregnancy, so dont expect to feel too different. Remember that at week 3 you may not have missed your period yet and may have little idea that youre pregnant. Even if youve been trying to conceive with your partner, you wont find any physical signs of pregnancy to reveal that youve got a little person growing inside.
If youve been trying for a baby, or even if you havent but think you might be pregnant nonetheless, why not take a pregnancy test to make sure? Nowadays, home testing kits are as accurate as a urine or blood test at the clinic and a lot more convenient. Just be sure to carefully follow all the instructions for doing the test and reading it afterwards. If the result is negative, don’t assume you’re not pregnant you may have just tested too early.
Weeks Pregnant In Months
When youre expecting, its quite easy to lose track of how many months pregnant you are because youre so focused on counting weeks. Well, were here to tell you that youve officially entered the second week of your ninth month of pregnancy.
There are a lot of things going on in there with a baby, and a lot of changes happening in your body as it prepares for labor and delivery. Lets find out all about it.
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Due Date Based On Conception
This method calculates your due date based on the date of conception by assuming a gestation period of 38 weeks from the date of conception.
Now, Kelly Culwell, M.D., an obstetrician-gynecologist and Forbes Health Advisory Board member, notes that the date of conception isnt always a reliable method for determining your estimated due date. Its often incorrectly estimated due to date of intercourse, which can be several days off from actual date of conception based on the sperms ability to survive for five days in the reproductive tract, she says.
First Day Of Last Period
Most pregnancies last around 40 weeks , so typically the best way to estimate your due date is to count 40 weeks, or 280 days, from the first day of your last menstrual period . You could also subtract three months from the first day of your last period and add seven days.
The first day of your LMP is how most health care providers estimate a baby’s due date. But remember, it’s only an estimated due date, not a deadline for your baby to arrive. Just 4 percent of babies are born on their estimated due date.
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How To Calculate How Many Weeks You Are
Example:count one week to the nextuntil you reach the present date.
LMP = December 2, 2022
1st Wed = December 9, 2022 = 1 Week2nd Wed = December 16, 2022 = 2 Weeks9th Wed = February 3, 2023 = 9 WeeksYou are 9 Weeks and 1 Day pregnant
Another method to calculate how many weeks pregnant you are is to:
How Many Weeks Am I Formula:LMP = Last Menstrual PeriodHow Far Along Am I Formula:LMP = Last Menstrual Period*LMP date may be adjusted if unknown or following ultrasound.
Each of these methods will give you the gestational age of your pregnancy.
When Should I Call My Doctor
A note from Cleveland Clinic
A due date calculator helps you plan for your babys arrival. Keep in mind that a due date calculator is only an estimate. Youll need to see your provider to confirm the date. Your due date may change when you have a prenatal ultrasound. Your provider may even change your due date more than once during your pregnancy, but it usually only changes by a few days. Knowing when to expect your new family member allows you to prepare mentally and physically. An accurate due date also helps your provider monitor your health and the health of your baby.
Last reviewed by a Cleveland Clinic medical professional on 10/07/2021.
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# 24 And 25 Weeks Pregnant
Week 24 is important for viability over 50% of babies born now would survive if they receive specialized care.
Although you certainly dont want your little one to come out yet, its good to know youve passed the beginning of viability.
Each week you progress pass this raises the babys chance of survival significantly .
At 25 weeks your baby is filling out and beginning to look more like a newborn, than a little alien. Your baby may reach out and grab his umbilical cord.
She is gaining good control of her arms and hands now. His taste buds are forming, and he weighs about 1 1/2 pounds.
Actual Length Of Pregnancy
The actual length of pregnancy varies significantly among women. Just 4% of babies are born on their estimated due date, while 70% are born within ten days. The remaining 30% are born more than ten days before the due date or more than ten days after.
The reference above provides a delivery birth range of 38 weeks and four days to 41 weeks and three days with a probability of 70%.
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Pregnancy Term & Due Date
Pregnancy is a term used to describe a womans state over a time period during which one or more offspring develops inside of a woman. Childbirth usually occurs approximately 38 weeks after conception, or about 40 weeks after the last menstrual period. The World Health Organization defines a normal pregnancy term to last between 37 and 42 weeks. During a persons first OB-GYN visit, the doctor will usually provide an estimated date at which the child will be born, or due date. Alternatively, the due date can also be estimated based on a persons last menstrual period.
While the due date can be estimated, the actual length of pregnancy depends on various factors, including age, length of previous pregnancies, and weight of the mother at birth.1 However, there are still more factors affecting natural variation in pregnancy terms that are not well understood. Studies have shown that fewer than 4% of births occur on the exact due date, 60% occur within a week of the due date, and almost 90% occur within two weeks of the due date.2 As such, while it is possible to be fairly confident that a persons child will be born within about two weeks of the due date, it is currently not possible to predict the exact day of birth with certainty.
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