You may like to take a look at charts for crown-rump length , biparietal diameter , femur length , abdominal circumference , gestational sac diameter , yolk sac diameter and intrauterine fetal weight. If you have problems understanding and calculating your due date, check out and download a copy of the Ob calculator by York Winston.
Hutchon's site and the Gestation Network also provide pregnancy calculators. A large number of mails I received are about fetal anomalies, I have therefore tried to put together a Catalogue of Web pages which describe in some detail specific congenital anomalies that are diagnosable by ultrasound.
You can visit the page here. I am pregnant for 7 weeks. I went for a scan yesterday and was told I should have a full bladder. They made me drink 4 cups of water and my bladder was almost bursting at the end of the session. Is this really necessary? A full bladder is usually necessary when the scan is done abdominally and in the early part of pregnancy.
This would tend to lift the uterus up a little bit and being in front displaces the bowels away and act as an echo-lucent windows for the ultrasound to pass through. Ultrasound doesn't go through air as in the bowels well but transmits perfectly through liquid as in the case of the urine in the bladder.
Your doctor will be able to see things so much more clearly with the full bladder there especially the presence or absence of fetal heart beat. In a vaginal scan however, a full bladder will not be necessary. I am pregnant for 6 weeks and 5 days, I turned up for a scan today but I was told they could not see the fetus. They say this could be due to my irregular menstruation, and ask me to return for another scan next week. What does that mean? I am quite worried. Usually we should be able to see the fetal heart beat quite clearly by about 6 and a half weeks, particularly in a vaginal scan.
In a woman with irregular and slightly longish cycles say, 35 days verses a usual 28 days , the day of ovulation would actually be postponed to 1 week on top of the 14 days in the usual case, that is, she ovulates on Day The number of days between the first day of menstruation and the date of ovulation the follicular phase is variable, but the number of days between ovulation and the start of the next menses the luteal phase is generally rather constant at about 14 days. So if you have a menstrual cycle of 42 days, then you ovulate on Day 28!
Add 14 days and your next menses will come. Therefore if you have a longish cycle then you ovulate late and your fetus will be less advance then it should be, meaning it will appear smaller or cannot be seen at all.
Of course, if for other reasons, the fetus has not grown, then it will also show up smaller. The way to get around making a correct diagnosis of which is which is to repeat a scan in about a week's time, so that those who are smaller because of a date factor will then be found to have grown.
I am 7 weeks pregnant and had a scan yesterday. My doctor said everything is fine and he could see the heart beat. He said the chance of a miscarriage is very small and he looks quite confident when he said that. Is the comment valid? Nowadays most Obstetricians would believe that the cause of the majority of 1st trimester miscarriages is a defect in the embryo, and is basically a chance event.
Imagine a sperm coming together with an egg to develop into a fetus. This involves many millions of cell divisions and changes so that the chance of something going wrong is very great. If it happens very early on in development say 4 to 5 weeks , the growth of the embryo may come to a stop. The heart will cease to beat. The body in due course rejects the non-viable material, giving rise to the process of 'miscarriage'.
Therefore if by about 7 or 8 weeks, everything appears intact with a good going heart beat, it is quite reasonable to say that the pregnancy will most likely carry on. My wife is 9 weeks pregnant with twins, she has on and off bleeding and spotting for the past 3 weeks. She already had 3 ultrasound scans, all of which showed two fetal heartbeats. What are the known causes of spotting and bleeding? Given a "positive" ultrasound, how does that weigh against the fact that there has been occasional spotting and bleeding?
It is always difficult to pinpoint the exact cause of bleeding in a first trimester pregnancy. In your wife's case, it could just be bleeding from the cervix or the edge of the placenta which is bigger and more close to the cervix because of the twin pregnancy and these situations generally bear little or no significance. Sometimes the bleeding can carry on up to the second trimester. If the heartbeat is present, the same still holds i. In the old days any vaginal bleeding in the early part of pregnancy is called ' threatened abortion '.
With the advent of Ultrasound, we have to say this is a misnomer, as in the cases when the fetal heartbeat is seen, the pregnancy is not ' threatened '. I had a scan yesterday. I am pregnant for about 30 weeks. My doctor said the fluid around the fetus is much decreased and told me to take more rest.
He seems to look worried. A decrease in the amount of fluid around the fetus oligohydramnios can be normal in most cases, and apparently can be improved with more rest, which in turn improves the circulation to the uterus.
A significant reduction in the amount of liquor, however, is associated with retardation of growth in the fetus and possible congenital malformations. Your doctor looked worried because he might be unsure as to whether the fetus is suffering from an abnormality or not. In such a case, referral to a centre with expertise in scanning for fetal malformations may be indicated.
But remember, most cases would be quite normal and bed rest with improve things. The amount of liquor around the fetus does not have any relationship with the size of the mother or how much water she is drinking everyday. My doctor has diagnosed polyhydramnios. I am currently 33 weeks gestation. I was sent to a specialist for a more advanced sonogram and told that nothing is wrong other than the polyhydramnios. I had a tri-screen at 18 weeks and it was negative as well. I still can't help but worry that something is wrong.
My concern is that a birth defect undetected by a sonogram may still be a possibility and that the doctor may be keeping something from me. He is reluctant to do an amniocentesis. It seems that they want to give me as little information as possible and I can't help but wonder why if everything is o. A detailed ultrasound examination at 33 weeks should be able to diagnosis most, if not all the recognizable causes of polyhydramnios.
A significant proportion of pregnancies with polyhydramnios does not have any demonstrable birth defects in the fetus. An amniocentesis may indeed be helpful for planning necessary treatment but your doctor probably felt that the chance of finding something wrong with the amnio is too small to warrant doing it. That is actually good news. I don't think your doctor is trying to keep things away from you.
My doctor said that my baby's head is a little 'smaller than dates' whereas the limb bone and the abdomen were quite on par with dates. Does that reflect that I have a baby with an abnormal head? If this is your first scan, then it may be a problem with dates. If your dates have been quite well validated from a previous scan, then it appears your baby could have a slightly smaller head. All of us has a different size head, isn't it? And mind you, your doctor measures the side-to-side 'diameter' of the fetal head and if your fetus has a relatively 'flatter' head it will appear 'smaller' on measurement.
This may simply reflect the head's configuration rather than anything that you should be alarmed about. It will need a size lag of up to weeks before one would start to consider malformations such as microcephaly small head syndrome.
I had a scan at 8 weeks and my doctor said the fetus is only 7 weeks, and it was because I had irregular menstrual cycles. I had another scan at 34 weeks and my doctor now said the fetus size was only 31 weeks. Should I stick to the earlier scan or should I use the later scan to fix my Due date? If my fetus is smaller, would it be wise to leave it in the womb for as long as possible so that it can grow bigger and get more mature?
You should always use the result of a scan that is done earlier on in pregnancy for 'dating' purposes as it will be more accurate. In the later part of pregnancy the measurements will be affected by growth variations and will no longer reflect the fetal 'age' correctly. In your case, the findings apparently indicated that you have a smaller than average baby. It is incorrect logic to think that babies who are not growing well should be left inside the womb for a longer period of time.
In fact the reverse should be true. The baby may be better off outside than in and for this reason we sometimes have to deliver these babies well before the actual due date. I had a scan at 34 weeks. My doctor said the estimated weight of the fetus is 2.
Is this too small? How much should an average baby weigh at 34 weeks? The weight for an average size fetus at 34 weeks is about 2. We would say a baby is small-for-dates when it's weight is below the 10th percentile line, and in the case of 34 weeks this will be 1. Please take a look at the Intrauterine weight chart. Your baby is on the small side, but not too small. You must also know that estimating the weight of the fetus with ultrasound measurements sometimes can incur errors of over 10 percent.
Your doctor will usually make an assessment together with other ultrasound findings. I will have a scan tomorrow.