As much as 50 percent more blood can be flowing through a pregnant woman. More blood flowing through the system means more blood reaching the placenta, and that means nourishment for the growing baby. Hooray! Yay for healthy babies!

This increase in blood, while of course being a healthy, normal part of being pregnant, can cause a few symptoms that said pregnant woman might consider, well, less than pleasant.

Some are just aesthetics, and while in our culture things related to appearance can seem to be of the absolute utmost importance, perhaps you want to know about some of these as potential health concerns — or, on the other hand, health, or, at the very least, pleasurable, benefits, if you know what I mean.

More intense action in the bedroom is for sure reported by some pregnant women. Being with child can really get the blood flowing! Women might also find themselves, well, hot in other ways, as in flushed, sweating, and wanting to sit in that air-conditioned car, please oh please, just a little bit longer. Preggos also sometimes find themselves just so, so tired. They might feel faint, dizzy, or lightheaded, or also swollen like a balloon that’s ready to pop.

I bet you’ve heard of some of these symptoms before, but did you know they were all related to a boost in blood? Here, from bumps in the butt to bonuses in the bedroom, are 15 changes that can go down when a woman is pregnant, and all due to increased blood volume!

15 Crazy Swelling

A lot of pregnant women notice this in their feet. During my second pregnancy, especially, I think I noticed a slightly fuller appearance to my usually quite prominently contoured face. I know for sure that when I bought shoes in my usual size online, I was like, “Hey, these stupid shoes run small!” once they came in the mail.

Edema is the fancy-shmancy medical term used to describe swelling of the body. Extra fluid can get trapped in the body’s tissues. The body is retaining more water and of course going through blood-flow changes. As mentioned, feet — especially toward the end of the day — tend to be a common place to notice the swelling. The hands, legs, and ankles can be other noticeably swollen areas. Any part of the body can be affected, though.

Try resting with your feet up throughout the day if you can. Certainly try to get some feet-up R&R in at the end of the day, especially days where you’ve been at work the whole time or unable to get off your feet for a spell here and there.

14 Hot As Heck

I already tend to run hot. I have my entire life. I don’t live somewhere that ever really gets all that cold, compared to most places in the world. Still, though, on days where others were wearing wool sweaters and scarves, I’d show up wearing flip-flops and tank tops, sometimes with wet hair. My mom always said I must have a fast metabolism. (I’ll take it!) The point is, once I was pregnant, I did not need any warm-weather clothes — that’s for sure!

Not only are your muscles doing more work to get an increasingly large body around all the livelong day; you also have like 50 percent more blood circulating around in there. To be able to handle this, the blood vessels dilate somewhat. The blood can come to the surface, making you want to strip down and run around through the sprinklers. Metabolic and hormonal changes can make the heat rise, as well.

Anyone who’s been pregnant before is quick to commiserate or offer you a lemonade or Popsicle on a warm summer day.

13 Head Is Spinning

Here’s a neat trick: when you are getting up from bed or any reclined position, do it slowly. Swing your legs out of bed and place each foot on the ground. Gradually elevate your head and your core. Then, even if you think you’re all set to spring out of bed, sit for a moment or two, or three, more. Dizziness can really take you by surprise, and when pregnant, it’s easy to feel light-headed at times, especially when going from a prone or supine position to an upright one.

Progesterone causes an increase in blood flow to the baby. This means lowered blood pressure for mom as well as less blood flowing to the brain. All that can make mom feel like whoa.

As the uterus grows larger and larger during the second trimester, it can put pressure on the blood vessels. In the later stages of pregnancy, the hefty babe you’re carrying around in there can put pressure on a major vein called the vena cava if you lie down on your back. When pressure is put on this vein that transports blood from the lower part of the body to the heart, it can cause dizziness, too.

12 Omigod I’m Tired

Once dinner - and honestly, quite often a decadent chocolate dessert - had been had, I often really saw no reason not to immediately floss, brush, and plop down in bed. Pregnancy can make you feel really, really tired sometimes!

Exhaustion in the first trimester was hard, mainly with my second pregnancy while I was also experiencing a few weeks of morning sickness, taking care of a toddler, working, and happened to have also come down with a super bad cough and cold. Rough times. Even if you are feeling otherwise healthy and well, though, being pregnant can take a lot out of you!

Think of all the work the body is doing — all the energy it takes to create a whole new person in there — and I suppose it makes sense. Right at the start and toward the end of this journey called pregnancy, can be prime times for feeling too tired for life. Some women report a boost in energy during the second trimester, as well as at the very, very end — when a surge in your desire to clean, organize, and generally get stuff done can be your nesting instinct kicking in and that labor may be starting soon!

What’s causing you to feel so pooped at other times, though? Hormonal changes cause increased blood flow so that baby gets the nutrients she needs. Blood sugar and blood pressure are lower, too. Progesterone levels are higher. What does this all mean? Feeling like you need more Z’s.

11 Hello, Huge Veins

All the extra blood pumping through your system may make veins at the surface of your skin appear bigger and more obvious. When veins are gnarled and enlarged, they are known as “varicose veins.” I bet you never thought of this one when you were dreaming of becoming pregnant! I know I didn’t! I also actually didn’t really notice this common symptom, personally, during the two times I’ve been pregnant.

For some women, though, the growing uterus puts pressure on a major vein called the vena cava. This can then put additional pressure on the veins in the legs. The veins may bulge out from the surface of the skin. They might appear blue or purplish. They might appear to have a few more twists in them than a regular vein. They may be uncomfortable, causing achiness or itchiness, and hot feelings on the skin. The extra burden on the veins due to increased blood volume is to blame.

10 Sweating Up A Storm

Can someone open a window? And actually, is it really necessary that I wear clothes right now? They’re all wet with sweat, anyway.

Sweating more during pregnancy is a very common symptom. The surging hormones cause other physical changes that can contribute to feeling hot — in general or sometimes in flashes — and therefore sweating much more than you did before you were with child.

More blood is flowing. Your metabolism is increased. These can both cause a major increase in perspiration. Your body temperature can tend to be higher, in general, when you are pregnant.

In some cases, more sweating can apparently be related to hyperthyroidism, which is a change with the thyroid gland. Increased sweating when experienced alongside heart palpitations and some other symptoms might mean you should seek medical care.

Generally, though, sweating more when pregnant is just a normal part of the whole glorious process. Plan and dress accordingly, so that when you feel hot, you can take off your sweater, enjoy a cold beverage, or relax for a while in front of a fan.

My place has all south-facing windows and gets very, very warm even on days that are just in the mid to high 70s. My husband and I bought a fan for every window and every room, and I still have them placed strategically in front of my nursing chairs.

9 So Baaad It’s Driving Me Mad

“Increased libido” would be a very medical way to say it. Another way to phrase it would be “increased sex drive.” The way I might say it is wanting to jump my hubby’s bones all the time.

Hormones surge, causing increased blood flow and other physical changes.

Breasts can become larger and more sensitive. For some women, this is A-OK. (For others, it is, at times, uncomfortable.) The vulva has more blood flowing to it along with many other body parts. It can become engorged and more sensitive than it was before. This can lead to things feeling pretty, pretty good. This can lead to a pregnant woman wanting to do it again. And again. And again.

I’ve said it before, and I’ll say it again: with an uncomplicated pregnancy and the doc’s OK, why not go right ahead? You have the time to enjoy bonding with your partner, before a little one — or another little one — is on the scene!

8 Straight Up Sucks To Sleep

I like to sleep on my back. We’ve been watching a TV show where a character climbs into bed, lies flat with head resting neatly on the pillow, arms folded loosely across the chest, eyes closed, sleeping soundly, and my husband has said, “Who sleeps like that? … Oh wait, I guess you do.” Ahh, so restful and supported, with no arm wedged underneath me or a pillow, no hip or knee bent a little too far this way or that way.

When you are pregnant though, due to, again, issues related to blood flow, it’s often advised that you sleep on your left side. This better allows the heart to do its increased work of pumping all that extra blood around your system. Either side is better than on the back, because that way the ever-larger uterus isn’t putting too much pressure on the major vein called the vena cava.

Being on your side lets blood flow well to the placenta and therefore nutrients to reach the baby. If, like me, it can be hard to catch some Z’s while forcing yourself to be in this position, buy a support pillow or wedge a comforter under your bump and/or between your knees, and godspeed.

7 Booty Bummers

What do you call a varicose vein sticking out of the butt? A hemorrhoid!

Some lucky ladies get to experience these bad boys for the first time during pregnancy. Others partake in the delight that is hemorrhoids after laboring and pushing to deliver a baby.

They can appear as small or grape-sized lumps, well, protruding down there. These are blood vessels that have swollen up. Sometimes they are inside of the rectum; sometimes they are sticking out.

What can they cause? Rectal bleeding. What else? Discomfort. What else still? Itching.

Progesterone has caused a pregnant body’s veins to relax so all the extra blood can flow more easily through them. This means the veins can swell more easily. Another fun little side affect of progesterone? It can slow down the digestive tract and cause things to get a bit backed up, aka constipation. Straining to have a bowel movement can cause hemorrhoids to appear or make them worse.

6 Blood Pressure Drops Like Whoa

An extra, growing body to nourish means the need for much more blood in a pregnant person’s body. The heart rate increases to supply the necessary blood to the placenta, nourishing the baby. Veins relax, letting the blood flow through. That’s why in the first half of pregnancy, blood pressure generally goes down.

Low blood pressure might contribute to a pregnant woman feeling dizzy. It also might make her feel fatigued. I know from experience that it can help to get up from sitting and standing positions very, very slowly. As mentioned earlier, put each foot on the ground, pause for a moment, and probably for an extra moment or two beyond that, before getting up. It can be easy to feel like you’re fine and ready to rock and then stand up only to realize you feel faint and lightheaded. Having low blood pressure, however, might not be something you really notice and end up being no big deal.

5 Oh-So-Intense Big Os

Let’s talk about sex. More specifically, let’s talk about sex during pregnancy. There are a few factors here that may just contribute to some pretty intense orgasms, possibly more intense than at any other time in a woman’s life.

Hormones are one thing to consider. Remember when you were a teenager? Remember those, well, interesting years when you were going through puberty? Similarly, perhaps, to during those times that you may or may not have blocked out from your memory bank, hormones are surging. Let’s just say that if you had a boy over and your parents were home, they might be telling you that you better leave your bedroom door open, young lady.

Another thing is flowing freely: blood. More blood flow throughout your body means more blood flow to reproductive organs, as well. What do you get when you have increased sensitivity, raging hormones, and, quite possibly, are feeling super pumped on the partner that helped you to make a baby in the first place? Some pretty intense stuff.

4 Careful About Clots!

With extra blood and extra blood flow, keep in mind the potentially dangerous blood clot. Blood clots have a purpose in the body: to stop bleeding. They can form at other times, though, as well. These masses of blood change from liquid to semisolid states. Sometimes they dissolve on their own, but sometimes they can be very dangerous and require treatment.

The answer to preventing clots is the answer, perhaps, to many things in life: a healthy lifestyle. Staying active, with the doctor’s okay, is one thing to do. Walking and mild exercise such as you may have already been carrying out before you became pregnant may be good to maintain. (This is not to mention what a great joy it can be to get outside and get moving!) When you travel by airplane, it is recommended to take breaks from sitting to walk around and get things moving.

Persistent pain, soreness, or redness could signal a clot, so if this happens, get thee to a doctor! Some anticoagulants are considered safe for use during pregnancy, and these may be used to treat it.

3 Swelling, High Blood Pressure, And Proteins — Oh My!

Preeclampsia is a set of conditions coming together to create one dangerous condition. Later on in pregnancy, some women have high blood pressure. If there is protein in the urine, as well, it is called preeclampsia.

This is very serious and can be seriously dangerous. Blood flow becomes restricted. When blood flow is restricted, a mother’s internal organs can be harmed, and the growth of the baby can be limited.

There are various levels of severity when it comes to preeclampsia, according to Pregnancy & Newborn. After diagnosing the condition, a doctor will advise a pregnant woman in what to do to cope with it. In some cases, a woman may be hospitalized. In others, she may be put on bed rest, where she is, as you might have guessed, confined to bed. The baby may need to be delivered early. Many times, the condition is not preventable, so keeping an eye out for warning signs and listening to the doctor’s instructions is the way to go.

2 Quit Playing Games With My Heart

An extra sound heard during a heartbeat is known as a heart murmur. It is actually rather common. It occurs when blood is not flowing normally through the valves of the heart. Of course, some people already just have them. Sometimes, though, the increase in blood volume caused by the hormonal changes of pregnancy can cause heart murmurs. Probably not surprisingly, a doctor will need to be consulted to diagnose and treat this condition.

Healthy children sometimes have heart murmurs and then outgrow them when they become adults. These murmurs do no occur alongside other heart conditions, and they don’t require people to receive any treatments or make any changes to their lifestyles. Pregnancy is the other common time during which they may happen. Sometimes, though, murmurs indicate a problem. People experiencing heart murmurs may have no other symptoms and therefore not know that they have one. In other cases, murmurs might occur alongside symptoms including chest pain, a rapid heartbeat, fatigue, shortness of breath, or skin that is bluish in color.

1 The Itsy Bitsy Spider Veins

Sometimes these occur at the same time as swollen, varicose veins, or sometimes they occur all on their own. They are small in size, and they are red or bluish in color. Spider veins usually appear on a woman’s legs, though they can also be seen on the face or other places on the body.

They can happen in sort of a pattern, perhaps the shape of a spider web. (Get it now?) They can also look like a collection of short little lines that are not connected.

Once again, it’s the increased blood volume that occurs during pregnancy that is a big factor here. Way more pressure is put on the body’s circulatory system, so veins of all sizes, including tiny little ones, can swell.

Some women get them; some women do not. Genetics are a factor here, as with many other symptoms experienced during pregnancy. The good news: they often don’t last forever and can sometimes be prevented with a healthy lifestyle and diet.

Sources: HowStuffWorks.com, PNMag.com, Livestrong.com, MayoClinic.org, Parenting.com, AmericanPregnancy.org, BabyCenter.com, Health-And-Parenting.com, WhatToExpect.com, HealthLine.com, Parents.com, HopkinsMedicine.org, WebMD.com