Guest Author - Secola Edwards

You may or may not already be in the second trimester of your pregnancy, but there are questions that still abound in your mind. What do the babies look like by now? How much do they weigh? Are their arms forming? What about their lungs, are they healthy?

Let's solve some of the mystery for you here and take a look at the second trimester development of your babies.

Second Trimester

The second trimester of a multiple pregnancy typically begins around 13-14 weeks and last through week 27-28, depending on your given due date. The babies will undergo dramatic changes during this phase. They will progress from the first trimester where they began as a clump of cells to becoming a fetus. This is a very exciting time for expectant parents.

Why?

One major reason is that the ill side-effects of your pregnancy will begin to dissipate, if they haven't disappeared all together. This will make for a much more enjoyable time, especially for a mom carrying twins. The babies are growing at a rapid rate, beginning the second trimester approximately at a quarter pound and 2 inches and ending the period at a whopping 2 to 3 pounds and 11-14 inches each.

Probably the most significant event during your pregnancy will be the babies' first movement that you will be able to feel. They began moving during the first trimester, but in all likelihood, you did not feel them. Terms for the babies' first movements are sometimes called flutters or quickenings, which can begin anywhere from 14-16 weeks. Some people compare the feeling of the first movements to the fluttering of butterfly wings or the rumbling feeling when there is excessive gas in the abdomen. The movements will become more intense and frequent as the babies grow and their limbs become stronger. I remember feeling movement all over my abdomen at any given time once the twins reached 19-20 weeks in development.

Other significant milestones the babies will reach during the second trimester include:

* Their arms and legs are growing longer and their head to body ratio no longer have that alien look as they are now more proportionate.
* Towards the middle of the trimester, roughly 19-21 weeks, the fluttering will become much more intense and officially become kicks
* Also towards the middle of the second trimester the babies have gained hearing. Reading to them and conversing with them is important at this stage of development as voices heard often become familiar sounds. This will aide in soothing them during times of stress after they are born.
* Towards the end of this time of development, you may see amazing pictures on an ultrasound such as hairs on their head, fingernails, eyelashes and eyebrows!

If the babies are born at the end of this trimester, they have a great chance at survival. Their lungs will be vulnerable, so an extended hospital stay will be required.

Keep in mind that all weights, measurements and time-lines given in this article are averages for a twin gestation. Every pregnancy is unique, even within the same mother.