You may find that you are experiencing more heartburn than normal now. Heartburn is a burning sensation in the throat, chest and upper abdomen. This is a very common complaint during pregnancy at 12 weeks. It is caused by an increase in the hormone progesterone during pregnancy. Progesterone relaxes the valve between your stomach and esophagus. This relaxation allows stomach acids to enter the esophagus and cause severe irritation, which gives you that burning sensation.
Some great suggestions to relieve and prevent heartburn are as follows:
Eat less at each meal and have six meals a day instead of three.
Chew your food adequately and eat slowly.
Drink liquids before and after your meals and not with them.
For heavens sake stay away from fatty and greasy foods which will only make the problem worse.
Stay away from fizzy drinks, citrus juices and spicy meals.
Do not eat before going to bed.
Raise the head of your bed or prop yourself up with pillows which will help minimize heartburn.
Consider liquid antacids… they work much better than the tablet forms.
At 12 weeks pregnant, your baby is 2.2 inches long from crown to rump, or 55 mm in length. This is comparable in size to a kiwifruit! Your baby is big enough at this point to be weighed. He or she weighs up to half an ounce this week!
Your little one's brain is starting to produce hormones at pregnancy week 12, and nerve cells are multiplying at a rapid rate. Brain synapses are also forming this week, which means that your baby can now feel some types of pain.
An exciting development now – your baby may be making a sucking movement with his or her mouth as early as this week. Your little one's mouth can open and close at this point in gestation, so your baby's time might be filled with sucking, yawning, and swallowing amniotic fluid.
Your baby's kidneys may be developed enough to start producing urine. (Believe it or not, but babies do urinate in the womb.)
Your baby's heartbeat is going strong. The average fetal heartbeat is around 167 beats per minute; this is double the speed of an adult's heart. Your little one's heart rate will slow down once you hit the middle trimester.
The umbilical cord is fully formed , but it will continue to get longer and longer as your pregnancy continues. The umbilical cord has an essential role in pregnancy – it supplies the baby with oxygen and nutrients.
For weeks, you've probably been asking, "When will I start to show in pregnancy?" You don't have to ask this question anymore. For most women, they are finally showing. You might not have a prominent bump yet, but you should be noticing a difference in your abdomen.
But if you're 12 weeks pregnant with twins, you probably have a nice sized bump by now. Pregnant women carrying twins or multiples often look further along, compared to expectant mothers with a single baby. You may also have a larger bump if you're been pregnant before.
By the end of pregnancy week 12, your uterus will pop out of your pelvis, and appear just above the pubic bone. As the weeks pass, it will continue to grow into your abdomen.
If you have started showing, congratulations. Your miscarriage risk is also lower now. A majority of miscarriages occur before pregnancy week 12. This is a wonderful week to announce the big news to your family and friends. Enjoy this wonderful week and your diminished first trimester pregnancy symptoms!
At 12 weeks pregnant, many of your uncomfortable first trimester symptoms – such as morning sickness (nausea and vomiting) and fatigue – are almost gone, or at least not as severe. You might also notice that you don't have to go to the bathroom as often.
As first trimester symptoms are starting to disappear, new symptoms will start to crop up, such as the following.
Heartburn is a common pregnancy symptom to expect now. Also called acid reflux, heartburn is an uncomfortable burning sensation in your chest and it's caused by hormonal changes. When you're pregnant, progesterone (a hormone produced by the placenta) relaxes the valve that separates your stomach from the esophagus. Since this valve is more relaxed during pregnancy, it's easier for acids in your stomach to seep back upward into your esophagus, giving you that burning feeling. Heartburn tends to get worse later in pregnancy, due to the expanding uterus pressing against your gastrointestinal organs.
Skin changes should also be expected. If you have freckles or moles, you may notice that they become darker. The skin around your nipples and areolas might also be darker. This is due to hormonal changes increasing the production of a melanin (a pigment that gives your skin color). Melanin is also responsible for giving you chloasma.
Chloasma (the mask of pregnancy) might be making its appearance. If you've noticed any discolored, brownish splotches or patches on your chin, cheeks, temples, or forehead, this is chloasma and it's a common pregnancy symptom. Up to 70 percent of all pregnant women will develop the mask of pregnancy. Exposure to sunlight can make these dark spots even darker, so make sure to protect yourself from harmful UV rays.
Acne is also a side effect of hormonal changes, and it's a common symptom.. Getting pimples, acne breakouts, and zits isn't any fun, but it should be expected. If you have regular breakouts before your period, you are more likely to have acne in pregnancy.
Your weight gain at 12 weeks pregnant may be as high as five pounds. Don’t stress if you haven’t gained this much. (Remember that each woman gains her pregnancy weight at different rates.) Just focus on the total recommended weight gain for your body size.
If you are carrying twins or multiples, it’s not uncommon for you to have gained 10 pounds by pregnancy 12 weeks. You will show sooner if you’re pregnant with more than one baby, too.
Many women worry that it is not safe to wear a seatbelt during pregnancy. The opposite is actually true. During your pregnancy, it is more important than ever that you buckle up, to protect yourself AND your unborn child. In the unlikely event that you are in an accident, a seatbelt can prevent you from hurling through your car window.
Remember that your baby has a thick layer of amniotic fluid surrounding him or her to protect him or her from any sudden jarring or impact that might occur during a minor collision. Most of the pregnancy related injuries that do occur during pregnancy are the result of car accidents, so it is important that you buckle up to reduce your risk of serious injury.
Do you need a special seat belt during pregnancy? Not necessarily. Your lap belt should fit over your thighs underneath your belly, and be tightened so that it is snug but not uncomfortable. It is important that you also wear your shoulder strap, with the strap placed between your breasts diagonally and resting against your chest. The shoulder belt should also be snug but not uncomfortable. Never use just one belt or the other, as you could be compromising your safety and that of your baby!
Many women wonder early in their pregnancy if they might be carrying twins. Your physician might start suspecting a twin pregnancy early in your pregnancy if your uterus is larger than expected. Most of the time, a uterus that is larger than normal is the result of a miscalculated due date rather than twins. However, your healthcare provider might opt to perform an ultrasound now at 12 weeks pregnant (though some perform one many weeks sooner) to determine if your date is correct or if you are carrying twins.
Some tell tale signs that you might be carrying twins include: larger than average uterus for your due date, larger weight gain early in pregnancy, more than one heartbeat, worse than normal morning sickness, and increased levels of AFP.
A twin pregnancy is usually considered a higher risk pregnancy, but that doesn't necessarily mean you will have complications. One of the more common risks associated with carrying twins is pre-term labor, but many people will go on to carry their twins to term.
There is a slightly elevated chance of miscarriage in multiple pregnancies. Sometimes a mother will lose one baby but go on to carry the other to term. Most of the time however, the risk of fetal loss is reduced after the 12th week of pregnancy. Typically women who lose one twin will go on to deliver the other baby without complication. If a twin is lost in the first 12 weeks of pregnancy it will actually be reabsorbed and not cause any harm for the health of the infant that is continuing its development in your body.
If you are carrying twins or multiples, you are also at an increased risk for developing preeclampsia, a condition that results in high blood pressure during pregnancy. Preeclampsia is more common in up to 20 percent of women carrying multiples.
Are there certain things you should consider if you are pregnant with twins? You may realize worse than normal pregnancy symptoms if you are carrying twins, but this isn't always the case. Horrible morning sickness can strike a mom carrying a singleton just as much as one carrying multiples. Symptoms of fatigue and general discomfort are sometimes greater in moms carrying multiples, particularly later in pregnancy or during the third trimester.
Almost half of all mothers with multiples will go into labor before 37 weeks pregnant. Many women assume that they will undergo a cesarean section if they are carrying twins, but this is not always the case. There is a good chance you will be able to deliver both of your babies vaginally, depending on the position they present in at birth, and whether or not you experience any complications such as preeclampsia during your pregnancy.
Some women will have to be put on bed rest during their pregnancy in order to help minimize complications such as pre-term labor. A woman carrying multiples will likely be encouraged to take things easy much earlier than a woman carrying one baby.
If you are carrying multiples, even during pregnancy week 12, it is very important that you remain well hydrated and eat nutrient dense foods to maintain your energy levels and stay healthy during pregnancy. The average weight gain for a twin pregnancy is usually 45 pounds, which is more than the 25-35 pounds recommended for singleton mothers.
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You may find that you are experiencing more heartburn than normal now. Heartburn is a burning sensation in the throat, chest and upper abdomen. This is a very common complaint during pregnancy at 12 weeks. It is caused by an increase in the hormone progesterone during pregnancy. Progesterone relaxes the valve between your stomach and esophagus. This relaxation allows stomach acids to enter the esophagus and cause severe irritation, which gives you that burning sensation. 
For weeks, you've probably been asking, "When will I start to show in pregnancy?" You don't have to ask this question anymore. For most women, they are finally showing. You might not have a prominent bump yet, but you should be noticing a difference in your abdomen. 
