Did you miss me? Well, it is a new year (+ one or so months, ok now I am up to 6 before I finally finished and published this post) and I am ready to start back up again. So much has happened since I last wrote. I promise not to take 2+ years off again, but I had a good reason. I started a new job, got pregnant, found out I was having identical twin boys, made it through most of pregnancy until I developed Pre-eclampsia, gave birth, made it through a short hospital stay myself and a slightly longer NICU stay for the boys, our daughter started grade school, we bought a townhouse, moved, switched our daughter’s schools, and on top of all of that I switched positions at my place of work. All of that brings me to the here and now. Each of these amazing adventures pulled and pushed our family like Willie Wonka’s taffy-pulling machine and it had an impact on all our lives. I have so much that I can write about and share, but first TWINS!
So, yes it happened. There is nothing like finding out that you are growing more than one embryo inside your womb to wake you up. Let me set the scene. I was 9 weeks along, my husband was out of town at a conference and I was fine with missing the first appointment since we had been through this before; so away I went to my Doctor for the first ultrasound. Everything was going great. We found a good strong heartbeat, the embryo appeared normal in shape, and measured exactly as it should for 9 weeks along. Then the faithful words of my Doctor, “let us take a look around” to see how the placenta and the rest of my uterus looked. Everything looked great, the placenta was in the right place and appeared attached correctly; and then it happened... “wait, did you see that?” I had seen it - another heartbeat- but it was in a different location than before. Then the words that came next I will never forget, my Doctor exclaims, “There appears to be another one, looks like you are having twins”. How could this be, twins don’t run in my family and I was fortunate that we were able to conceive without medical assistance in my slightly more mature age.
TWIN FACTS:
Twin births are a relatively rare event even though statistics show that they are becoming more common with the twin birth rate rising 79% from 1980 to 2014 (18.9 to 33.9 per 1,000 births; National Vital Statistic Reports). This “trend” has been attributed to an increase in the use of fertility drugs (which we fortunately did not need), as well as, an increase in maternal age (that’s me). In 2011, it was estimated that 36% of twin births and 77% of triplet and higher-order births were attributed to medically assisted conceptions such as the taking of fertility medications, in-vitro fertilization procedures (IVF), etc. (Kulkarni, 2013). Additionally, multiple births occur more often as women approach perimenopause, due to more of the follicle stimulating hormone (FSH) being produced. Although this production is normally a sign of a decrease in fertility, FSH is the hormone needed for an egg to mature for ovulation and having extra hormone can lead to more than one egg maturing and releasing. So, while women of “advanced” maternal age are less likely to get pregnant, if they do, they are more likely to have twins. That explains a couple of the reasons for having fraternal twins (or dizygotic twins), however, this was not my case at all - lucky me. Ours were identical!
IDENTICAL TWINS:
Identical twins, also known in the scientific community as monozygotic twins, occur when one fertilized egg (zygote) splits into two, resulting in the development of two separate embryos. This type of twinning occurs in 3.5 per 1000 births (compared to 33.9 per 1,000 births for all types of twin) and more interesting is that this statistic is fairly consistent across all demographics (race, geography and maternal age) for natural conceptions. The risk of monozygotic twins with conceptions using IVF is 2.25 times higher than natural conceptions (https://academic.oup.com/humupd/article/15/1/45/860625/The-risk-of-monozygotic-twins-after-assisted). Additionally, monozygotic twinning can occur at different times after conception which can result in different numbers of amnions (inner sac) and placentas the embryos will have during their development. Most Identical twins result when the zygote splits 4-9 days post conception (65-70%), leading to the development of two amniotic sacs and one placenta. This is how our baby boys developed. A split occurring 1-4 days post conception (25-30%) results in two amniotic sacs and two placentas. The rarest twins result (1-5%) from a late split at 9-12 days post conception resulting in only one amniotic sacs and one placenta.
The crazy thing is that why a zygote splits and the actual cause of monozygotic twinning is still relatively unknown. What we do know comes from a 2007 discovery which showed that for twins to occur the cells of an very early developing embryo (when it is still just a ball of cells) collapses leading to the ball splitting in half, resulting in two sets of genetic material that will then go on to develop into two separate fetuses. The lead researcher on the study, Dianna Payne, believes the split occurs because the cell junctions (where cells stick together) fail, possibly due to cell death or just weaken of the junctions themselves during the cell collapse.
https://www.sciencedaily.com/releases/2007/07/070702145537.htm
Another researcher, Dr. Bruno Reversade, has been studying the genomes of families from areas of the world that have higher frequencies of twins hoping to find the “twinning” gene. He speculates that the “twinning” gene does not allow cells to “stick” together within the blastocyst leading to the split in the genetic material. http://www.reversade.com/
Dr. Judith Hall, a pediatrician and clinical researcher who specializes in genetic factors that affect children’s growth, suggests twinning depends on the timing of fertilization. Most mammals know their fertility cycle and therefore mate when eggs are freshly ovulated, but Humans mate at any time with the possibility of an older egg that may more likely split.
So twins...yeah, although they are becoming more common they are still rare and identical twins are still even more rare, I guess the mystery of why is still part of their magic. Cause magic is definitely what you need to make it through the first couple of years (possibly longer, only time will tell).
