Life Within Life

Now that I'm posted in the Obstetrics and Gynaecology department, I get to see a lot of pregnant women. Its amazing to watch the ultrasounds of the fetuses, watch their hearts beat, watch them sleeping or waving their hands, sucking their thumbs and so on. Its probably one of the most beautiful things ever, and one of the most beautiful feelings too. Its also lovely to see the smile on the mother's face on seeing her babies heart beat, and its little feet and hands. I wouldn't know, but it is amazing to think that you are actually carrying another life within yourself.

I'll rant about some pregnancy related stuff now. I think I'll start with calculating or estimating the age of the gestation (pregnancy).

Gestational age (GA) is basically calculated from the woman's first day of her last menstrual period (LMP). Basically, you know that your expected date of delivery (EDD) is 40 weeks from your LMP or an estimated 280 days or 10 lunar months. The traditional method of calculation is (LMP - 3months + 7days) and then adjust the year accordingly. Nowadays, there are ready-made charts available for easy use. However, this method of estimation is rarely accurate. (It is after-all an estimation.)

Another method is by clinical assessment of the size of the uterus, which is usually useful upto 28 to 30 weeks. You measure the fundal height using a tape measure. The uterus maynot be palpable until 12 weeks. And by 30 weeks (some books say 32 weeks, some say 34 weeks) the uterus reaches the maximum possible height it can attain.

Fetal movement is usual appreciated by the mother between 17-21 weeks (5th or 6th month). This is referred to as quickening (in medical terms).

The more accurate method of assessment is the ultrasonography.

During the first trimester (first 3 months), the fetal crown-rump length (CRL) is measured. Formula for calculating GA from CRL is kinda complicated (I dont know it by-heart :$). The ultrasound machines usually auto-calculate the GA for you (hehe). Anyway, this method is used until about 12 weeks. This can also help assess fetal growth and development.

During the second and third trimester, the best measurement is bi-parietal diameter (BPD). You can also use head circumference (HC) or femur length (FL). However, BPD is almost always routinely done and is also the easiest. Again the ultrasound machine auto-calculates the GA. BPD refers to the diameter of the head between the two parietals (kinda like saying from ear to ear).

Okay thats all for now.