At 13 weeks pregnant, your baby is already 2.9 inches long from crown to rump, and he or she weighs up to 0.8 ounces. You could compare your baby to the size of a nectarine! Though your baby is significantly larger than last week, he or she is still considered pretty tiny.
Your baby's head is still huge at 13 weeks pregnant, but the body is starting to catch up. The arms and legs are lengthening this week, and you're baby's muscle control is developing. Although your baby has little control over the muscles right now, this will change in the upcoming weeks.
Up until this point in your pregnancy, your baby's eyes have rested along the side of the head. This week, the eyes are moving closer together. It won't be long before the eyes are situated in their rightful positions on the face.
At 13 weeks pregnant, your baby's toes have separated into individual digits, and they're all the same length. The joints in your baby's ankles have matured.
Your baby's skin is still transparent at 13 weeks pregnant, because your little one does not have underlying body fat. In the second trimester, he or she will build more fat layers and the skin will become less see-through.
At 13 weeks pregnant, your baby's intestines are also moving further into the body, and your baby's tiny pancreas is starting to produce insulin, which will be vital for regulating his or her sugar levels later in life.
Your baby's brain is maturing. The right and left hemispheres are beginning to connect. As the brain develops further, your baby will get more control over movements. In only ten weeks from now, your baby's brain will be fully developed.
Congratulations! Pregnancy week 13 marks the end of your first trimester. Next week, you'll be entering the second trimester – which is often referred to as the "honeymoon" of pregnancy. Your chance of miscarriage at 13 weeks pregnant is relatively low. Roughly 80 percent of all miscarriages occur before 12 weeks of pregnancy. Second trimester miscarriages can happen, but they're rare. You only have a 1 to 5 percent risk of having a miscarriage between 13 weeks to 19 weeks pregnant.
You are definitely showing now. As your uterus expands and grows larger, your internal organs are forced to shift their position to accommodate your baby's rapid growth.
Although your bump isn't that large yet and you probably don't need maternity clothes, you may find that your favorite pair of jeans no longer fit. It might be time for you to switch to wearing larger clothes. Some women find that baggy clothes and sweat pants are more comfortable at 13 weeks pregnant than their regular clothes.
Try to wear loose-fitting clothes, if it's possible. This will help you feel better, and it may reduce the abdominal discomfort that you may feel this week. Tight clothes may cause you to overheat.
At 13 weeks pregnant, you are probably feeling remarkably better than you have in the previous weeks. Your nausea and fatigue should be greatly reduced by now, and you may even find that you have a renewed sense of health and vigor.
Starting at 13 weeks pregnant, you may notice that you have more energy than before. For a majority of women, fatigue is decreasing with each passing week. Enjoy your higher energy levels in the second trimester. They won't last long. You are going to start feeling tired again in the latter part of your pregnancy.
Breast changes are common at 13 weeks pregnant and throughout your pregnancy. You may have noticed that your areolas are darker, and the blue veins in your breasts are more prominent. Some women also notice that there are tiny "bumps" surrounding the areola. These are called Montgomery's tubercles, and they are a normal pregnancy change.
Shortness of breath is a normal pregnancy symptom at 13 weeks pregnant, and it's often nothing to worry about. Feeling breathless can be alarming, but it's believed that up to 70 percent of all pregnant women will feel short of breath at some point during their pregnancies. Shortness of breath should be mild. If you're experiencing chest pain, a sense that you're not getting all the oxygen you require, or you have heart palpitations along with shortness of breath, contact your doctor or healthcare provider.
Mild abdominal discomfort is also relatively normal at 13 weeks pregnant, and it's due to round ligament pain. As your uterus grows, the round ligaments that surrounding it will stretch to accommodate your developing baby. During this stretching, the ligaments can irritate nearby nerve fibers, which causes the dull achiness or sharp pain that occurs when you change positions or move too quickly.
Swollen, tender gums is a common pregnancy experience at 13 weeks pregnant. Your body has double the amount of normal blood circulation in pregnancy, and this can soften your gums and cause minor irritation when you're brushing or flossing your teeth. Your tender and swollen gums may also bleed when you're brushing or flossing. This is pregnancy gingivitis, and you'll want to maintain good oral hygiene to prevent it from developing into gum disease.
It’s the final week of your first trimester, and your weight gain at 13 weeks pregnant is roughly five or six pounds. From this point in your pregnancy week by week onward, you’re going to gain at least one or two pounds.
It may be tempting to constantly weigh yourself to track your pregnancy weight gain, but you’ll want to resist this urge. Don’t worry about the pounds. Just try to eat as healthy as possible and exercise on a regular basis. You’ll want to aim for a weight gain of 25 to 35 pounds in total, if you’re an average size. You can easily achieve this by eating right and maintaining healthy lifestyle choices.
Spotlight on Increased Libido in the Second Trimester
Many women find that their libido returns after pregnancy at 13 weeks and throughout the second trimester. In fact, many women find they are more easily aroused in part due to the increased blood flowing through all parts of their body, including the genitals. Some women find that having relations is particularly arousing, and others find their climax is more intense than normal during the second trimester.
Along with an increased libido, however sometimes come misgivings, which can occur in either partner. You may find your partner is eager to have make love with you now that you are feeling better, but he is afraid that intercourse may harm the baby. By and large, making love during pregnancy is safe for most women, provided you do not have a high-risk pregnancy or are at risk for pre-term labor. If you still have misgivings, or if you find your partner is having misgivings, consider bringing him with you to your next appointment so your healthcare provider can help alleviate any concerns you might be having. Often this in and of itself is another way to initiate intimacy.
Talk Openly With Your Partner
If you are still having problems connecting with your partner, it is important that you talk with them openly about your needs, wants, desires, and concerns. It is important for your partner to understand that pregnancy can bring on feelings of depression, emotional liability, self-esteem issues, body image issues, and personal feelings regarding control. Try approaching your partner from a non threatening standpoint, and let them know your feelings. You should also work together with your partner to understand their feelings, which will help resolve any intimacy issues you may be having.
As your belly expands, you will undoubtedly have to come up with new and creative positions to engage in during lovemaking. This can be a fun and entertaining process for both partners. Keep in mind however that while some partners find the sight of their pregnant partners growing and blossoming body very arousing, others are turned off. This is not a reflection of how beautiful you are; all pregnant women are very beautiful, goddesses in fact in the eyes of mankind. The miracle of birth typically makes women more beautiful than at any other time in their life.
If you find that your partner simply cannot overcome their fear of intimacy during pregnancy, or find that your partner is turned off by pregnancy in general, remember that intimacy can still be expressed in many different ways. It is important that you remain close to your partner because you will need them for support and encouragement throughout your pregnancy. There are many forms of intimacy that do not involve intercourse. You and your partner can try a number of things to pleasure one another without actually engaging in lovemaking, and find this practice mutually satisfying throughout your pregnancy.
You may also find times when you simply feel too big and uncomfortable for lovemaking. This is another time when communication is very important, so your partner understands that you are not rejecting them, but you simply do not feel like 'your old self' at times. Remember when you communicate openly and honestly with your partner, the possibilities are endless. Your relationship will continue to be strong and remain close as long as you remember to speak freely and honestly with your partner, and ask that they do the same throughout your pregnancy.
Although your risk of miscarriage is lower at 13 weeks pregnant, second trimester miscarriages can occur. Some women are still at risk for miscarrying through their 20th week. In certain circumstances, a woman might be diagnosed as having an incompetent cervix.
An incompetent cervix is the result of a cervix that is too weak to stay closed during pregnancy. Typically what happens when a woman has an incompetent cervix is the baby is delivered too early to survive. This relatively uncommon problem is usually the cause of up to 25 percent of second trimester losses. A diagnosis of an incompetent cervix can be made using an ultrasound or a manual exam. Generally an incompetent cervix is diagnosed when the cervix is open more than 2.5 cm during pregnancy, or when the length is less than 20mm.
Unfortunately, an incompetent cervix is often only diagnosed after a woman has had one or two late miscarriages, or miscarriages that occur in the second trimester. There are some circumstances that may increase a woman's risk of suffering from this disorder, including: cervical trauma, congenital disorders and a previous D&C. Fortunately, there is a procedure called a cerclage that can be used to stitch the cervix closed. This is typically done between weeks 14 and 16, and it usually allows a woman to carry the baby to term. Remember that most women will not have an incompetent cervix, and they will have a high chance of carrying their baby to term after the 13th week mark.
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Congratulations! Pregnancy week 13 marks the end of your first trimester. Next week, you'll be entering the second trimester – which is often referred to as the "honeymoon" of pregnancy. Your chance of miscarriage at 13 weeks pregnant is relatively low. Roughly 80 percent of all miscarriages occur before 12 weeks of pregnancy. Second trimester miscarriages can happen, but they're rare. You only have a 1 to 5 percent risk of having a miscarriage between 13 weeks to 19 weeks pregnant. 
Many women find that their libido returns after pregnancy at 13 weeks and throughout the second trimester. In fact, many women find they are more easily aroused in part due to the increased blood flowing through all parts of their body, including the genitals. Some women find that having relations is particularly arousing, and others find their climax is more intense than normal during the second trimester. 
Although your risk of miscarriage is lower at 13 weeks pregnant, second trimester miscarriages can occur. Some women are still at risk for miscarrying through their 20th week. In certain circumstances, a woman might be diagnosed as having an incompetent cervix. 