The truth about pregnancy, week by week

Have you recently discovered you're expecting a little one? Congratulations! Pregnancy can be one of the most exciting times in a woman's life — however, if you don't know exactly what to expect, it can be one of the scariest times in your life, as well.

Don't fret, Mama! You're not the first pregnant person to ever walk the earth, and you definitely won't be the last. There's a multitude of resources for the expecting mother — online, in the library, and advice from your friends and family members who have done this before. Heck, there's a whole book about what you can expect when you're expecting — aptly titled What to Expect When You're Expecting. Of course, everyone knows moms-to-be can expect rapidly growing bellies, morning sickness, unusual culinary cravings, and people wanting to get a feel of that growing baby bump — but what's happening behind the scenes? 

Here's a look at the changes you can expect for your body and your baby throughout each week of your pregnancy. 

Weeks 1-4: Pregnancy or PMS?

Period pains or pregnancy? In the earliest stages of your pregnancy, it's likely you won't be able to tell much of a difference between the two! 

According to Healthline, early signs of pregnancy very closely mimic the symptoms caused by PMS. Symptoms caused by both pregnancy and PMS include breast swelling and tenderness, light vaginal bleeding or spotting, fatigue or trouble getting to sleep, nausea and aversion to certain smells and foods, changes in your mood or behavior, and abdominal cramping. If you're a woman, it's likely you've experienced one or all of the symptoms at some point in your life, even if you've never been pregnant. So it's completely understandable that early pregnancy symptoms are often so easily confused with PMS. 

While you're trying to figure out if you're even actually pregnant, baby has a lot of growing left to do. In the first four weeks of pregnancy, your little one is a teeny-tiny grouping of cells. According to WebMD, he or she is about the size of the head of a pin! Whaaa?

Weeks 5-9: Mood swings and tight jeans

By week five in your pregnancy, there's likely little doubt as to whether you're pregnant or not. You've probably taken a pregnancy test, excitedly told your family and friends, and had your first doctor's appointment with your bun in the oven. However, if there's still question regarding your mama-to-be status, look no further than your favorite pair of blue jeans. 

That's right — in weeks five through nine of your pregnancy, the pair of jeans you've had forever will probably start feeling just a little tight around the waist. Your belly is growing bigger because your little one is, too! Now is the time your little guy or gal is developing a mouth, nose, ears, and something that kind of resembles a human head. According to Baby Center, by week seven, your uterus will have doubled in size! 

Oh, and if you notice yourself getting frustrated with the little inconveniences in life, don't worry — according to WebMD, week eight is usually when moms-to-be start feeling a little moody. Morning sickness certainly doesn't help to put you in a better mood, so try to keep something on your stomach throughout the day to fight that queasy feeling. 

Weeks 10-14: Baby bump alert

There will be a number of graduations in your baby's life. Pre-K to kindergarten, high school to college, college to — well, the real world. But week 10 of your pregnancy can very well be considered your baby's first graduation. Why? Because your little baby bun has finally graduated from an embryo to a fetus! Hooray! 

By week 11, your baby is the size of a lime. According to What to Expect, your little one has developed hands and feet, nostrils, a tongue, and little fingers and toes! In fact, your baby is a growing machine! Your little one is the size of a plum in week 12, a size of a peach by week 13, and the size of a lemon by week 14. And a growing baby means a growing belly for Mommy. There will be many exciting times throughout your pregnancy, the least of which not being the first glimpse you see of a growing baby bump! Go ahead, Mama — take that mirror selfie and show of your new (adorable) baby belly!

Weeks 15-19: Butterflies in your belly

Bye-bye, first trimester — hello, second trimester!

For many moms-to-be, the most difficult part of pregnancy (aside from not being able to find a comfortable sleeping position as your belly grows bigger) is the first trimester of pregnancy. Luckily, the start of week 15 means that you're well into the second trimester of your pregnancy, which takes place from week 13 to week 28. And that's not where the exciting news ends! According to WebMD, some women start to feel their babies kicking around inside their bellies as early as week 13! Now that gives a whole new meaning to having butterflies in your belly. 

The second trimester is considered by many to be the least difficult three months of pregnancy, so you can expect the fatigue you've been suffering through to ease off a bit. Take advantage of this time to start planning for your little one's arrival — perhaps a nice, neutral yellow for the nursery? 

Weeks 20-24: Watch that belly grow!

Congratulations, Mama! You've reached the halfway point in your pregnancy. According to WebMD, you can expect to have your midpoint ultrasound between week 18 and week 22 of your pregnancy. It's also around this time that you'll be able to discover the gender of your little one — unless you'd rather be surprised, of course! 

According to Johnson Memorial, your growing baby is about the size of a banana by 20 weeks, so you most definitely have a bit of a baby bump. As WebMD points out, you've likely gained about 12 to 15 pounds by week 23 of your pregnancy. Your skin is probably feeling dry and uncomfortably itchy due to stretching, so make sure you keep some lotion on hand to combat the dryness. However, be sure whatever skincare products you use don't contain nasty chemicals that could potentially harm your baby, including (but not limited to) retinol, Targretin gel, and Panretin. 

Weeks 25-29: Hands off my belly!

Guess what? By week 26, you are officially into the third trimester of your pregnancy — only a few more weeks left until you finally get to meet your little one! It's a very exciting time in your pregnancy; but unfortunately, the last few weeks can be the most uncomfortable time in your pregnancy, as well. 

According to WebMD, by this point in your pregnancy, you can expect to be putting on about one pound per week. Both your belly and baby are growing at a rapid pace, which means more discomfort for Mama — and more people wanting to put their hands all over your growing baby bump. If you're not a fan of people touching your belly unprompted, don't feel bad — you're not alone. Don't be afraid to politely ask that people not touch your belly — after all, they probably wouldn't like you to rub their tummies, either! A bun in the oven doesn't give anyone entitlement to your body.

By week 29, you might notice signs of premature labor. Be sure you talk to your doctor immediately if you notice increased pressure in your pelvis, fluids leaking from your vagina, or contractions. 

Weeks 30-34: Where are your feet — and the cocoa butter?

You're in the homestretch now! Only a few short weeks until baby is here — and by this point in your pregnancy, you'll undoubtedly be anxiously awaiting his or her arrival. Not only are you ready to meet your little bun in the oven, but you probably feel like your belly can't possibly stretch any further. Well, we hate to be the one to break it to you, but it definitely can stretch further — and it will. Make sure you keep some pregnancy-safe cream on hand to combat those pesky stretch marks that come with a rapidly growing belly. 

According to WebMD, your baby likely measures about 18.9 inches long by week 32. Your little one is taking up pretty much all the space within your uterus (though you'll probably still feel some kicks from time to time). Those kicks and somersaults will slow down in the coming weeks, as your baby will have gained more than half its birthweight during that time, taking up even more space in your uterus. By week 34, your little one measures almost 20 inches long and is a whopping five pounds. They grow up so fast!

Weeks 35-40: Hello, Baby!

Here it is — the moment you've been waiting for!

One of the first signs that your baby will be making his or her way into the world soon is lightening, or the process of your baby's head moving into your pelvis before delivery. When lightening occurs, your belly will sit a little lower — and you'll probably feel the urge to urinate more frequently. You also may notice bloody discharge, loose stools, and — of course — contractions. When those contractions occur at intervals of less than ten minutes, labor has likely begun! 

Your delivery is divided into three stages. In the first stage, your cervix will begin to dilate — eventually dilating to ten centimeters! In the second stage, you'll be instructed to begin pushing to propel your baby through your birth canal, resulting in a successful delivery. During the third stage, you'll deliver your placenta. According to WebMD, the delivery process usually lasts somewhere between 12 and 14 hours for first pregnancies — and while labor may be painful, the feeling you get when you hold your little one for the first time will be well worth the wait (and the pain)!