Skip to main content

How to Survive the First Trimester of Pregnancy

  • Author:
  • Updated date:

Marissa is the writer of ThePracticalMommy and the blog Mommy Knows What's Best. She is a stay-at-home mom to four and was a teacher.

The First Trimester of Pregnancy

Learn how to survive the first trimester of pregnancy.

Learn how to survive the first trimester of pregnancy.

Your First Trimester

The first trimester of pregnancy can be an exciting yet frightening time for women, especially those who are pregnant for the first time. There's no need to worry; most of the things you will experience have been experienced by women for ages and now we're in an age when we understand so much more about pregnancy and how our bodies react to the stresses of pregnancy.

Beginning of the First Trimester of Pregnancy

Your pregnancy begins at least four weeks before you can get a positive pregnancy test, starting with the first day of your last period.

Your pregnancy begins at least four weeks before you can get a positive pregnancy test, starting with the first day of your last period.

When Does the First Trimester Start

The first trimester begins two weeks before there's even a chance you are pregnant. Crazy, right? Not so much. For a long, long time, health care professionals have been measuring pregnancy from the start of the last menstrual cycle, i.e. the first day of your last period. Pregnancy from there lasts approximately nine to ten months (~40 weeks). This is the most accurate way, aside from measurements by an ultrasound, to measure the timing of pregnancy.

The only other way to determine when pregnancy begins is to know the actual date of conception, but let's face it: who knows that? Very few people. For example, let's say you only have intercourse once during your cycle, right around ovulation. The sperm released can live up to five days and can meet the egg during any of the five days. Still think you know you're conception date now?

Back to the last menstrual cycle: let's say in a 28 day-cycle your period started on June 30th and you missed your next period, due around July 28th. If you're pregnant, your pregnancy started on June 30th, and by July 28th you're already four weeks pregnant. That's one third of the first trimester already!

If you have irregular menstrual cycles or you're not sure when you last menstruated, your doctor can give you an estimate of your dates based on measurements of the baby and your uterus during an ultrasound and pelvic exam.

When Does the First Trimester Begin?

When is My Due Date?

Your due date is calculated by using the first day of your last period. If you want to count it from there, your due date would be approximately 280 days from then, give or take a few days.

An easy way to figure out your due date is to take the first day of your last period, add seven days, and then count backwards three months. For example, if your last menstrual period was June 30, adding seven days would give you July 7, and three months back would be April 7. Your due date would be on or around April 7th.

An even easier way to figure out your due date would be to use a due date calculator online or on a smartphone app.

No matter how you determine your due date, it is just an estimate. Few women actually have their babies on their due dates. In a healthy pregnancy, babies can be born anytime after the 38th week until a week after the due date. Sometimes, babies will come a few weeks earlier than the due date. There's no sure way of knowing until you go into labor or have a condition that may indicate that you'll go into labor early. Only those who at risk for preterm labor will have a test called a fetal fibronectin that can indicate if preterm labor will not happen. The rest of pregnant women just have to wait it out!

What is the First Trimester Like?

If this is your first pregnancy, the first trimester may either be uneventful or the worst thing you've ever experienced. For those whose only symptoms are a positive pregnancy test and a growing bosom, the first trimester will be one of excitement and awe. For those who feel like they have a twelve-week flu, the first trimester will seem like it may never end. It's different for every woman and every pregnancy.

When I was pregnant with my firstborn, I had it pretty easy. I only felt tired and breezed through the first trimester. My second pregnancy was a different matter. I felt sick all of the time (whoever named it 'morning' sickness was so wrong!) and was very sensitive to smells and tastes. My third pregnancy was like my first (both ended up being boys!). My fourth pregnancy was worse than all the rest.

Either way, it can be exciting to think about the tiny baby growing inside of you. You'll be happy to tell family and friends (read more about sharing your news here), find out everything there is to know about pregnancy, and window shop for baby essentials.

Pregnancy Advice

You're going to get a ton of advice when you're pregnant from family, friends, and even complete strangers. The advice to trust should come from your doctor or health care professional.

Trusted advice can also come in the form of a book. I loved What to Expect When You're Expecting as a trusted pregnancy resource when I had questions. I also really liked the straightforward advice from the book Your Pregnancy and Childbirth Month to Month.

Dealing with Morning Sickness

Many women experience some level of morning sickness during the first trimester, most likely around the six weeks mark. At that point, the pregnancy hormones have fully kicked in and start messing with your delicate, balanced system.

'Morning sickness' is medically known as nausea and vomiting during pregnancy. The unknown person who named it was fairly wrong in his/her estimation about the timing; morning sickness can strike at any time, morning, noon, and night. For most women who suffer with it, the symptoms are prevalent during the early morning hours when their stomachs are empty and they're getting up out of bed after lying down for several hours. Other women, like myself, have it all day long.

Not all women vomit with morning sickness, but for those who do, it can be hard to keep food down and they may even lose weight during the first few months of pregnancy. It is important for those women to stay hydrated and eat what they can to have balanced nutrition for the baby.

The rest of the women who have morning sickness tend to just get nauseous or very dizzy, and they may even gag. To me, it felt like my throat was always tense and my stomach was queasy, along with having excess saliva. Add to that certain smells or even the sight of certain foods and I'd gag and have to remove myself from the room.

This too shall pass. For most, morning sickness symptoms go away around the 14th week, in the beginning of the second trimester. Others may suffer a bit longer while some stay sick for the entire pregnancy (sorry!).

Morning Sickness Symptoms

SymptomsWhat Can Make Morning Sickness Worse







sensitivity to smells


overall feeling of being sick

getting up too fast

excessive saliva


Bleeding in Early Pregnancy

Bleeding is something no woman wants to experience, especially during the first trimester as it may indicate a miscarriage. Believe it or not, many women experience some sort of bleeding during pregnancy that has no link to miscarriage.

If you have some light bleeding without cramping, it could be something minor. Some women spot lightly around the time of their period during pregnancy, but it could just be leftover blood from the last period or just the change in hormones. Other reasons for bleeding in early pregnancy include problems in the urinary tract, sensitivity of the cervix during intercourse, subchorionic hemorrhage, or polyps on the cervix.

If you experience bleeding with cramps and lower back pain, call your doctor immediately. It could be a sign of a miscarriage, molar pregnancy, or an etopic pregnancy. The doctor will want to test your hCG levels and perhaps ultrasound to see what is causing the bleeding and cramping.

Weight Gain During Pregnancy

Gaining weight during pregnancy is something else that's usually on a newly pregnant woman's mind. In the first trimester, you should expect to gain about one to five pounds of weight, although many women will gain more if they fall for the 'eating for two' fallacy. Most of this weight will come from your increasing blood supply and perhaps a bit of water retention and shouldn't come from double cheeseburgers with bacon and four scoop sundaes.

It's important not to gain too much during the first trimester. During the second and third trimesters is when you'll put on the most weight and already be uncomfortable from the growing baby, let alone from extra weight gain. Be easy; the weight you gain should steadily increase. You only need about an extra 300 calories a day, which can be a yogurt or an apple. Anything more will just add to your maternal fat stores and be harder to lose after you have the baby.

To help with a steady weight gain, you can add in an exercise routine to your every day life. Not only is something simple like walking or swimming easy to do, it will help you stay healthy and strong during your entire pregnancy.

Healthy Weight Gain While Pregnant

You should only gain as much weight during pregnancy as is indicated by your BMI.

You should only gain as much weight during pregnancy as is indicated by your BMI.

Tests During the First Trimester

Your first visit with your doctor may not be until your sixth or seventh week of pregnancy, although some doctors may see you sooner. Before that visit, you may be asked to give a blood sample so that your hCG levels (the hormone that indicates pregnancy) can be measured. During that first visit, you may have one or two tests done: a urine pregnancy test to be sure of pregnancy and an ultrasound to determine the due date. These firsts tests do nothing but to set the dates and perhaps the initial measurements with which to compare later on in your pregnancy.

Other tests during the first trimester may or may not include:

  • Blood tests for anemia, Rh factor, HIV or other sexually transmitted diseases, and immunity to rubella or chicken pox
  • Blood test for the levels of glucose in your system, to determine if you have gestational diabetes
  • Urine tests for excess sugar or protein in the blood
  • Chronic Villi Sampling (CVS) for those who are 35 or older to test for genetic defects
  • Blood tests for diseases known to exist in certain racial or ethnic backgrounds, like cystic fibrosis or sickle cell anemia
  • Ultrasound to detect genetic defects such as heart defects or Downs Syndrome

You may have some or you may have none of these tests, depending on your background and your health. Speak with your doctor if you have any concerns about any testing that may be done or any testing you think should be done.

How Does the Baby Grow?

During the first trimester of pregnancy, your baby will do a lot of growing, but still only be as big as a small lime or a medium sized shrimp, measuring 2-3 inches from the crown of the head to his/her bottom at the 13th week. That's pretty small!

In these critical weeks, much is happening. The ball of cells that resulted from the meeting of sperm and egg look more like a human towards the end of the first trimester. All major organs have formed, and the heart begins to beat by the sixth week. The placenta grows and takes over from the yolk sack that nourished the baby. Eyes, nose, ears, fingers, and toes are all present, even though they won't be done forming for a few more weeks. The external reproductive organs also start to begin showing, but they too will not be evident for a few more weeks.

If you have had any ultrasounds by now, you wouldn't be able to see too much nor would you be able to determine the baby's gender. In the beginning of the trimester, the baby won't look like much of a baby on the screen, but by the end of the trimester, you may be able to see a profile of your baby's face.

Things to Avoid During First Trimester of Pregnancy

To make sure that you and your baby stay healthy during your pregnancy, you'll want to avoid some things, such as alcohol, illegal drugs, foods that may contain harmful bacteria, certain medications, difficult working conditions, and anything that will make you sick. For a more complete list, read What to Avoid When You Are Pregnant.

Surviving the First Trimester of Pregnancy

Whether it's the best trimester of your pregnancy or the worst, you too can survive the first trimester of pregnancy. Just think: thirteen weeks down, twenty seven weeks to go! You can do it!


This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.

Questions & Answers

Question: How can I know if I am carrying twins at 6 weeks pregnant?

Answer: You may find out via ultrasound.


Marissa (author) from United States on March 17, 2019:

Musrat, every pregnancy is different.

Musrat Bibi on March 13, 2019:

Hi im 41 just found im 5 weeks pregnant. My feedings are very different.i hve tummy pain nd a funny feelings. This is my fourth pregnacy

Kristie on December 05, 2017:

Thanks I really enjoyed..

Dianna Mendez on August 14, 2012:

Well done! I loved your poem on a mother's love. The special way you wrote this information will make it so helpful to young mothers.

Marissa (author) from United States on August 12, 2012:

cclitgirl, I'm glad you like my tips! I sure do have experience. :) Thanks for reading and commenting!

Cynthia Calhoun from Western NC on August 12, 2012:

Good tips here. You've explained things so well and it sounds like you have lots of experience. :) Thanks for sharing these.

Marissa (author) from United States on August 10, 2012:

randomcreative, I appreciate your feedback! Thanks so much for reading and commenting!

Marissa (author) from United States on August 10, 2012:

TToombs08, thanks for reading, commenting and voting up!

Marissa (author) from United States on August 10, 2012:

Janine Huldie, thanks for your comment! Sure, you can link to this article. I appreciate the vote and the sharing as well! :)

Marissa (author) from United States on August 10, 2012:

Aw, Billy! Thanks for the support! :D

Rose Clearfield from Milwaukee, Wisconsin on August 09, 2012:

I always enjoy your articles about pregnancy! They are so well laid out and detailed. Great resources for anyone anticipating or going through pregnancy.

Terrye Toombs from Somewhere between Heaven and Hell without a road map. on August 08, 2012:

Great information on what to expect on the first trimester, Practical Mommy! Nicely done! Voted up and more.

Janine Huldie from New York, New York on August 08, 2012:

This was so very good and detailed about the first trimester. I have been writing a series of blog articles on here about my firs tpregnancy and just finished the first 3 chapters (which concluded the 1 trimester), would love to include this one as a link for others to read. Let me know if that would be ok. Thanks!! Also, have voted and shared too of course.

Bill Holland from Olympia, WA on August 08, 2012:

I just dropped by to give you some support. Obviously I won't be needing this hub, but the information is great and you did a wonderful job of preparing the hub for visual presentation. Great job!