Pregnancy is a common process that many females encounter throughout their lifetime. We were all brought into the world as a result of a pregnancy. During the long forty week process of fetal development, we were able to develop into the person we were born as. In a normal pregnancy, an egg is dropped from the ovaries where it is then fertilized, forming a zygote, to begin fetal development (BetterHealth, 2012). Sometimes, the egg can split causing twins, triplets, etc. One of the rarest types of pregnancies is a conjoined twin pregnancy, which occurs in every 1/100,000 live births (G.Rosica, D.Bucari, G.Pastore, A.Musella, 2020). In a conjoined twin pregnancy, the egg begins to split (in effort to end up with what is commonly known as an identical twin pregnancy) but it does not fully separate from one another (MayoClinic, 2019). The first 8-12 days after conception would be a normal range in which monozygotic twins split; it is believed that conjoined twins are a result from late splitting, usually 13-15 days after conception (MayoClinic, 2019). A conjoined twin pregnancy will result in the mother to have similar symptoms as a regular monozygotic pregnancy (A.R. Afzal and F.J. Montero, 2021). At six weeks of pregnancy, hormones are released that prevent the mother from having a normal period (Betterhealth, 2012). From 7-8 weeks, the mother is able to have an ultrasound screening to view the babies; this is the earliest time in which a conjoined twin pregnancy can be depicted (X.W.Liang, Y.Y.Cai, Y.Z.Yang, Z.Y.Chen, 2020). Apart from the normal symptoms of pregnancy, a conjoined twin pregnancy may result in more nausea, greater fatigue, and/or a faster growing uterus (MayoClinic, 2019). The conjoined twins can be fused at any part of their bodies: chest, abdomen, spine, trunk, pelvis, and/or head (MayoClinic, 2019). Conjunction at the thorax and/or abdomen accounts for over 50% of the total conjoined twin cases (A.R. Afzal and F.J. Montero, 2021). The site in which the twins are conjoined at and what organs are involved depict whether or not they can be considered for separation surgery after birth (A.R. Afzal and F.J. Montero, 2021). Unfortunately, the mortality rate of a conjoined twin pregnancy is high for the fetuses (X.W.Liang, Y.Y.Cai, Y.Z.Yang, Z.Y.Chen, 2020). In fact, the total survival rate of conjoined twins is 7.5% (A.R. Afzal and F.J. Montero, 2021). Factors that play into this rate are the complicated nature of the pregnancy and the separational surgery, if applicable (A.R. Afzal and F.J. Montero, 2021). Complications during pregnancy are often due to the physical characteristics of the conjoined twins, with most cases having a conjoined heart or liver, making it difficult for the fetuses to survive (G.Rosica, D.Bucari, G.Pastore, A.Musella, 2020). In the rare case that the pregnancy is able to last full term, the fetuses must be delivered by cesarean section (MayoClinic, 2019). Even after birth, risks run extremely high leading to 70% of conjoined twin births dying within the first 48 hours (X.W.Liang, Y.Y.Cai, Y.Z.Yang, Z.Y.Chen, 2020).





References: 
Afzal, A. R., & Montero, F. J. (n.d.). Conjoined Twins. In Statpearls. essay. 
Giovanna, R., Daniela, B., Giovanni, P., & Angela, M. (2020). Thoracopagus conjoined twins: Early diagnosis by ultrasound, a case report. Clinical Medical Reviews and Case Reports, 7(4). https://doi.org/10.23937/2378-3656/1410305 
Liang, X.-W., Cai, Y.-Y., Yang, Y.-Z., & Chen, Z.-Y. (2020). Early ultrasound diagnosis of conjoined twins at eight weeks of pregnancy: A case report. World Journal of Clinical Cases, 8(21), 5389–5393. https://doi.org/10.12998/wjcc.v8.i21.5389 
Liang, X.-W., Cai, Y.-Y., Yang, Y.-Z., & Chen, Z.-Y. (2020). Early ultrasound diagnosis of conjoined twins at eight weeks of pregnancy: A case report. World Journal of Clinical Cases, 8(21), 5389–5393. https://doi.org/10.12998/wjcc.v8.i21.5389 
Mayo Foundation for Medical Education and Research. (2019, July 31). Conjoined twins. Mayo Clinic. Retrieved April 13, 2022, from https://www.mayoclinic.org/diseases-conditions/conjoined-twins/symptoms-causes/syc-20353910 
Pregnancy – week by Week. Pregnancy – week by week – Better Health Channel. (n.d.). Retrieved April 13, 2022, from https://www.betterhealth.vic.gov.au/health/healthyliving/pregnancy-week-by-week#conception 

One Comment

  1. A conjoined twin is a person who is fused with their twin at any portion of the body. A conjoined twin pregnancy is the rarest complication in pregnancy though it is not an extraordinary occurrence. It occurs approximately one out of every hundred thousand live births – notice that this does not include failed pregnancies. It differs from a regular twin pregnancy in that the egg does not entirely split apart since the separation begins to occur too late in the pregnancy. The normal period of separation is 8-12 days after conception, yet conjoined twins begin to separate 13-15 days following conception. Between 7-8 weeks a conjoined twin pregnancy may be identified by an ultrasound. Even if a conjoined twin pregnancy is found, nothing different is done from a regular twin pregnancy until the birthing process – conjoined twins must always be delivered through a cesarean section. A woman pregnant with conjoined twins, will experience the normal symptoms of pregnancy – though likely in larger proportion. Nausea and fatigue may increase, and the rate of uterus growth will be higher. Conjoined twin pregnancies have a high mortality rate largely due to combined vital organs, such as the heart or the liver, which make survival very difficult for the babies. Due to this high mortality rate, conjoined twin pregnancies are more common than perceived since not many make it to term. As often as possible, depending on the risks associated with the site of fusion, surgery is performed to separate the twins.

    Naomi Bailey

Leave a Reply

Your email address will not be published.