{"id":28890,"date":"2019-01-09T09:57:00","date_gmt":"2019-01-09T17:57:00","guid":{"rendered":"https:\/\/www.avawomen.com\/?p=28890"},"modified":"2019-05-02T11:17:50","modified_gmt":"2019-05-02T18:17:50","slug":"4-weeks-pregnant","status":"publish","type":"post","link":"http:\/\/www.avawomen.com\/avaworld\/4-weeks-pregnant\/","title":{"rendered":"4 Weeks Pregnant: Your Symptoms and Baby’s Development"},"content":{"rendered":"

If your baby (now a blastocyst) didn\u2019t implant by the end of last week, it will do so this week. During <\/span>implantation<\/span><\/a>, the blastocyst burrows into the endometrium, which is the <\/span>mucous membrane that lines the<\/span> uterus. Before implantation happens, the blastocyst will break out of its protective covering, and an exchange of hormones will help the blastocyst attach.<\/span><\/p>\n

This happens when molecules on the embryo’s surface interact with molecules on the uterine wall, which will create a sticky environment that allows the blastocyst to attach\u2014sort of like a rolling rubber ball getting caught in a puddle of honey or syrup. <\/span><\/p>\n

Your mucus plug will develop<\/span><\/h2>\n

At this point, estrogen stimulates the production of mucus from the glands in your cervix, which will then soften, swell, and pump mucus into the cavity until there are no gaps left. Progesterone causes the mucus to thicken until the cervix seals up. The final <\/span>mucus plug<\/span><\/a> i<\/span>s about the size of a quarter with about two tablespoons of mucus.<\/span><\/p>\n

(If you\u2019re interested in <\/span>tracking your pregnancy<\/span><\/a> week by week\u2014Ava can help.)<\/span><\/p>\n

How big is my baby?<\/span><\/h2>\n

Baby\u2019s Length: 0.01 in.<\/span><\/p>\n

Baby\u2019s Weight: 0.04 oz.<\/span><\/p>\n

How is my baby developing?<\/span><\/h2>\n

Even though your baby is only the size of a poppy seed, a lot of significant developments are already happening.<\/span><\/p>\n

The cells of the blastocyst now burrowed deep into the wall of your uterus, continue to divide rapidly. <\/span>The inside of the blastocyst is the embryo; the outside of the blastocyst will later go on to become the <\/span>placenta<\/span><\/a>.<\/span><\/p>\n

The placenta releases the hormone human chorionic gonadotropin (<\/span>hCG<\/span><\/a>), which not only keeps you from releasing additional eggs but also stimulates the ovaries to produce estrogen and progesterone, hormones critical for a healthy pregnancy. <\/span><\/p>\n

The placenta will soon become your baby\u2019s source of nourishment and waste removal as it channels nutrients and oxygen from your body to your baby and your baby\u2019s waste away from you.<\/span><\/p>\n

The yolk sac and amniotic sac are also beginning to develop. The fluid-filled amniotic sac will cushion and protect your baby. The yolk sac will provide nourishment until the placenta is ready to take over. <\/span><\/p>\n

Your baby\u2019s physical features and traits are taking shape<\/span><\/h2>\n

Even more amazing: your baby\u2019s hair color, eye color, sex, and unique family traits like dimples or a widow\u2019s peak have already been determined by the chromosomes you and your partner have provided, although it will be quite a while before they take shape. Your baby even has the basic form of a face, with large dark circles for eyes.<\/span><\/p>\n

The heart and brain are developing<\/span><\/h2>\n

It\u2019s important to avoid any exposure to toxins right now\u2014and throughout the first trimester\u2014as your baby\u2019s internal organs are going through their initial development. <\/span><\/p>\n

The embryo continues to grown and now has three distinct layers of cells\u2014the endoderm, mesoderm, and ectoderm\u2014that will develop into specific parts of your baby’s body. The endoderm, the innermost layer, will become your baby’s liver, lungs, and digestive system. The mesoderm will soon be your baby’s skeleton, muscles, kidneys, and heart. The ectoderm, or outermost layer, is on its way to becoming your baby’s skin, hair, eyes, and nervous system.<\/span><\/p>\n

A sheet of cells has already begun to create the neural tube, where your baby’s brain, spinal cord, and backbone will form. Because this process happens so early in your pregnancy, it’s essential to ensure you’re taking in adequate folate. Folate drastically reduces the likelihood of neural tube defects like spina bifida and anencephaly, which can be disabling or fatal to your baby.<\/span><\/p>\n

What\u2019s happening in my body?<\/span><\/h2>\n

Next week, in week 5, is when many women start to begin feeling pregnancy symptoms. So now\u2019s a good time to talk about some <\/span>early signs of pregnancy<\/span><\/a>, as these changes may tip you off even before you get a positive pregnancy test result. <\/span><\/p>\n