What a baby looks like and how they will act are, in many cases, predetermined by their parent's genetics. But a fetus' gestational environment can also play a role in who they become. Most expectant women are warned that drinking alcohol, smoking and even eating a few strange things like deli meats and sushi can have serious consequences for the growth and development of their unborn babies.

But what about how a mother feels, thinks, or says? It is normal to wonder how one's behavior during pregnancy affects a growing baby. And with so much information about what is okay and what is not okay during pregnancy, it can be quite hard to have a guilt free day to think about what mom wants.

Yet it is true, there are so many ways that the decisions moms make over those nine months can affect a baby for the rest of his or her life. Not to be bombarded by everything already online and in forums which may or may not be true, here are fifteen surprising factual ways that things pregnant moms do can affect their baby's character, and tips for what moms-to-be can do to help their babies in the long run.

15 Your Choice Of Foods

Introducing fish low in mercury and eggs into your prenatal diet has been shown to make babies smarter over time, according to a study found in the American Journal of Epidemiology. Fish like salmon and sardines have been shown to reduce the symptoms of autism, support a healthy brain, and improve their ability to take tests as a child.

Omega 3 fatty acids, found in many fish, have been prescribed by many obstetricians as supplements for pregnant women for their proven benefit to fetal brain development.

Implementing egg yolks into your diet has similar benefits for your baby's brain.

Egg yolks contain choline, a sort of vitamin, which has the abilities to supercharge your babies brain by improving memory retention and information processing speeds. Though egg yolks should never be eaten raw during pregnant, some cooked yolks are the secret ingredient to a smarty pants baby.

14 Your Deepest Thoughts

Think positively! Now more than ever positive thinking is essential for you and your baby's development. Growing babies know their mother's thoughts. Plain and simple. They may not think them themselves but they feel the effects of their mother's thoughts, be they positive or not.  So if you are thinking things like 'I don't want this baby.' they will know and it could affect how they address others and you for the rest of their lives. They could have attachment issues or issues with trust and feelings of abandonment.

So take some time to think positively about your baby. Let them know how loved and wanted they are. It’s important that your baby is brought up by love. It is normal to allow your thoughts to wander, however, and it can be a drag knowing that for nine whole months even your thoughts are not your own. But relax, it's temporary, and the gift of motherhood is forever.

13 Your Innermost Feelings

Hormones play a HUGE roll in how we are feeling while acting as a human incubator. But letting those hormones get the best of us can be detrimental to your baby and ultimately how they will carry themselves when they get older. Your baby can feel what you feel.

If you are stressed or anxious your baby will be stressed and anxious and will by default grow believing that those sensations are normal responses to dealing with daily activities.

Being anxious and stressed can also limit your baby's physical development. Babies who develop in stressed-out mommies are developing in an environment with high cortisol levels leading to babies who are at higher risk for allergies, eczema, and asthma. So be happy. A little nervousness is normal, but try to feel as happy as you want your future baby to be, because at the end of the day how you feel will determine how they feel about the world.

12 The Music You Play

The "Mozart Effect" is the phenomenon discovered in 1993 stating that babies who listen to Mozart's classical music in utero and as newborns grow up to be smarter children. The lasting effects of this phenomenon have been discussed and attempted to be disputed, but scientists have determined that one thing remains indisputable, music seems to prime our brains for certain kinds of thinking.

After listening to classical music, adults can do certain spatial tasks more quickly, such as putting together a jigsaw puzzle. The classical music pathways in our brain are similar to the pathways we use for spatial reasoning. When we listen to classical music, the spatial pathways are "turned on" and ready to be used. Though the lasting effects of the music remain unknown, while babies are developing in utero, why not encourage further development of spatial reasoning by cranking up some tunes.

11 Talking Out Loud To The Baby

The sound of a mothers voice is crucial to a baby's development. Babies in the womb are more attuned to high pitch tones than deeper ones, meaning that if a mothers voice is more shrill when a baby is born he or she may develop an aversion to high pitched voices and may wind up hating the sound of their own mother's voice, according to speech pathologist Dr. Alfred Tomatis.

If your voice does run on a higher octave the chances of your baby hating your voice are low, but you should still talk to him or her anyway.

Engaging with your baby before and after birth lead to children who are more alert, and more participatory in conversation. So sit down and get comfortable, start talking to your little one. It may seem strange at first, but after a while, you may find yourself getting into a routine and may even get a few kicks or flutters in response.

10 Basking In Natural Sunlight

With enough sunlight comes enough vitamin D. Scientists have discovered that vitamin D deficiency can put unborn babies at risk to have a low birth weight and put moms at risk for preeclampsia and gestational diabetes. Sunlight has also been linked to feelings of euphoria and happiness. Since your baby feels what you feel getting enough natural sunlight is essential for cooking up a happy baby. Vitamin D is produced in our skin that affects the amount of calcium the body absorbs and is important for bone growth and development.

Not enough vitamin D can also lead to osteoporosis, arthritis, and diabetes. Although spending all day in the sun is ill-advised especially since pregnancy makes your skin very sensitive, but just 10 minutes of natural sunlight can make a world of difference in your baby's development.

9 Monitoring Your Sugar Intake

No alcohol, no smoking, no stressing and not even the same clothes, surely some sugar indulgence is okay over the course of nine months, right? Sorry moms, wrong. A 2016 study published in the Journal of Pediatrics said that women who consumed more sugar during pregnancy resulted in babies and children who grew up to be less active.

High sugar intake during pregnancy can result in obesity. In fact, moms who drank just one sugary drink per day had babies with a 0.15 higher fat mass than those who did not.

Sugar during pregnancy is also linked to asthma and allergies.

We know cravings can be a bit hard to manage, but trying more nutritious options to the typical chips and ice cream may help your little one in the long run. Hoping your future son or daughter will be an Olympian? You may want to trade in that bear claw for a salad.

8 Loading Up On Coffee

Ever feel a bit jittery after your morning brew? Now imagine how you would feel with the same amount of caffeine and a semi-formed nervous system. They say limiting your coffee intake to one cup a day maximum while pregnant is important, but they rarely tell you why. Caffeine increases blood pressure because it is a stimulant, it also increases the frequency of urination which can lead to dehydration, especially during pregnancy.

So what's that got to do with your baby's character? Caffeine crosses directly over the placenta and since your baby's metabolism and nervous system are not fully developed, your baby can not metabolize caffeine the same way you can, which can make your baby jittery and lead to abnormal sleep patterns as they get older. Don't want an insomniac for a kid? Take it easy on the caffeine.

7 Your Interactions With The Baby’s Father

Babies whose fathers were present during pregnancy are more likely to have a longer gestational age and be less at risk for death in infancy during the first year of life. This doesn't mean that if you are a single mother your child will not live a long healthy life,

but studies have shown that mothers who have support from their partner during pregnancy are happier, healthier and more likely to keep up with prenatal care.

This effect on mothers directly affects the baby, which leads to a longer and happier life. If a father figure is not in the picture, having ample support can provide the same effects. Having someone to make you feel comfortable in your growing an changing figure as well as your ability to parent once your bundle of joy arrives. Stay happy and parent on.

6 Hitting The Gym

Getting enough exercise is essential to one's health regardless if you are pregnant or not. But did you know that when you are done working out, your body releases mood-boosting endorphins that travel directly to your baby? Making your baby calmer, happier, and more at ease. Exercise also increases blood circulation and pumps more blood to your womb, which enhances your baby’s overall development.

But it doesn’t stop there, practicing your aerobics during pregnancy target your baby’s brain, helping to improve brain function and spatial learning in particular­–making your baby smarter and a quick learner who can retain more information. Exercising before your baby comes will also make labor and recovery after birth, easier–which in turn allows you to take better care of your newborn helping he or she build a strong independent character.

5 Monitoring Your Mental Health

If you've had depression before, you're more likely than other women to have depression during pregnancy. Babies born to moms with depression are often more irritable, less active, less attentive and has fewer facial expressions than babies born to moms who don’t have depression during pregnancy. If you have been diagnosed with depression or another mental health-related issue treatment options are available. Just be sure to check with doctors about possible effects those can have on your unborn child, in some instances side effects of medication can be just as bad as the effects of depression.

Some research says certain antidepressants may cause a baby to be irritable or have feeding trouble.

Researchers have found that taking a selective serotonin reuptake inhibitor (SSRI) while pregnant may be linked to a higher risk of miscarriages, birth defects, preterm delivery and behavioral problems, including autism. Around 3 percent of women who take antidepressants during pregnancy report using an SSRI.

4 The Things You Say

Similar to your thoughts and feelings, what you say out loud to others and to your growing baby can have a huge impact on the type of person they become. A 2013 study in the Proceedings of the Natural Academy of the Sciences, suggests that language learning begins in utero. Surrounding your baby with languages you want he or she to learn and speaking out loud allows your little one to familiarize themselves with the environment they will be born into.

The study also suggests that speaking out loud allows your baby to recognize your voice and those you surround yourself with frequently. This helps with baby's safety mechanism and allows mom to soothe baby more easily since he or she can recognize your voice. So warm up those vocal pipes and get talking. Encourage your support system to speak to your belly as well. Play tapes if you would like to teach your baby another language to encourage word and sound recognition. Some say they can see the difference in as little as the first two months of life.

3 The Places You Go

Are those kicks getting more intense at certain times during the day or in certain locations? That's because where you go while you're pregnant, especially during the third trimester can directly affect your little one.

Loud noises can disturb your growing baby and make him or her agitated and jumpy.

When they grow older they could have noise aversions or on the other hand, have trouble waking because they are so used to noise, which could make it difficult to feed your newborn.

Being in areas with second-hand smoke can cause damage to your newborn's brain and overall growth since the toxins found in smoke can seep into your skin and pass the placenta, not to mention the chemicals you are breathing in. During your pregnancy be mindful of where you agree to go because one night out could result in a lifetime of harmful effects to your little one.

2 Reading In Utero

Calming, relaxation, lower maternal stress, and bonding are all great reasons to start reading to your unborn baby. But when you throw in a greater likelihood of language ability and word recognition, advanced cognitive skills, and problem-solving, it seems that not reading to your baby prenatally is disadvantageous for all those involved. Scientists say for the most lasting effects of reading to your baby, parents should begin as early as six months, by then the ears and brain are developed enough for the baby to benefit from the interaction.

There is no perfect book to read either, studies show that no matter the text, the benefit is in the experience. "Whatever text you choose to read to your unborn baby – funny or classically heartwarming – it’s the process of prenatal reading that matters. The experience of reading will surely benefit your little one just through the sharing time spent together and the soothing rhythm of familiar voices," school librarian Megan McCoy Dellecese said in an article about reading in utero.

1 Exposure To Air Pollution

Breathing outdoor air pollution caused by traffic, industry and even dust during pregnancy may slightly increase the risk that a baby will be born at a lower birth weight, according to a large, international study.

While women can't always change where they live or work, avoiding rush hour traffic as well as idling trucks, buses, taxis, and cars may help.

In case that is not an option, some moms have resorted to carpooling or wearing protective masks when outdoors.

One can combat some of the effects of air pollution by increasing your daily intake of fruits and veggies during pregnancy, which is good news for moms with a long commute or those living in highly populated areas. So while you are hosting your little one be mindful of where you are and how fresh the air is that you're breathing in, since it all goes to your baby.

References: The Guardian, Live Science, Fear Free Child Birth, March of Dimes, The Bump, and The United States National Institute of Health.