Pregnancy Week by Week

Get a window on what’s happening in your pregnancy, week by week. From week four to week 42, your baby is experiencing a miraculous transformation from a clump of cells to a fully formed (and totally cute) newborn. Just imagine, as early as five weeks, your baby is already starting to form major organs (heart, stomach, liver, and kidneys) and systems (digestive, circulatory, nervous). By eight weeks, your raspberry-sized womb-mate is moving her arms and legs. At the beginning of your second trimester (week 14), your wee one is sucking his thumb. By week 28, the first week of the third trimester, baby (now as big as an eggplant) is prepping for breathing, developing his eyesight and packing on pounds in anticipation of life outside the womb. Each week is a new miracle. Less miraculous is how a mom-to-be may feel. Pregnancy Week-by-Week charts your baby’s development but also lets mom know what she might be feeling during each week of her pregnancy. Pregnancy week by Week includes everything mom needs to know to feel a sense of control over her pregnancy. Each week offers a complete guide to what you might feel, your must-do’s, your nice-to do’s, and answers and advice on everything pregnancy-related. Plus each week’s guide offers tips on maintaining a healthy and comfortable pregnancy from strategies on coping with pregnancy symptoms (morning sickness anyone?) to ideas for healthy eating, and pointers on talking to your OB. Let us guide you along your pregnancy, week by week.

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Q&A: When's my due date?

I'm very confused about my due date. I found out I was pregnant a week ago. I saw a nurse practitioner and she told me that I would have an ultrasound in two weeks to see how far along I am. My husband came home from deployment on July 1st. [Today's date: July 25.]

Re: I'm very confused about my due date. I found out I was pregnant a week ago. I saw a nurse practitioner and she told me that I would have an ultrasound in two weeks to see how far along I am. My husband came home from deployment on July 1st. [Today's date: July 25.]

The Bump Expert

I know it can be very confusing, but there is a simple explanation for the difference between your calculated weeks of pregnancy and how far along you are in your pregnancy according to conception date. The best way to explain this is with some basic info about the menstrual cycle.

Pregnancy is calculated based on the average menstrual cycle, which lasts 28 days. The first day of menstrual bleeding marks the first day of the menstrual cycle. This is called your LMP, or last menstrual period.During the first few days of the cycle, menstrual bleeding (your period) occurs as the uterus sloughs the lining that developed in the previous cycle. Afterwards, uterine lining (endometrium) grows again in preparation for possible conception.

Approximately two weeks into this cycle, ovulation occurs. The few days before and after this event is when you are most fertile. If during this time you have intercourse and sperm is released, fertilization(and thus, pregnancy) can occur. After fertilization and throughout pregnancy, the endometrium does not slough (meaning no menstrual bleeding) because it is now supporting the developing baby. If fertilization does not occur, the endometrium disintegrates and menstrual bleeding follows, signaling the beginning of a new cycle.

When calculating the weeks of pregnancy, we include those two weeks from the first day of the LMP to the approximate date of ovulation and conception. Because the first day of your LMP is the easiest part of the cycle to notice and record, that is where the beginning of the menstrual cycle and your pregnancy is measured from. It is about halfway through the average woman’s menstrual cycle that she ovulates and therefore conceives. So, just as your ovulation calculator indicates,your date of conception should coincide with right about the time your husband came home from deployment.

Whew…no need to worry there! So your little embryo may be only four weeks old, but you are six weeks pregnant. It sounds a little silly, but you aren’t really pregnant for about the first two weeks of your pregnancy. Finally, your estimated due date (EDC or EDD) is then calculated as 40 weeks from your LMP... And yes, this does mean that baby is actually only 38 weeks old when born.

Denise Gershwin, CNM

Q&A: When's my due date?

Not sure when it is haven't no period last one was feb 18

joycelinnhaff |


Can't remember when my Last period was

rockergirl84 |


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