Medical Perspective on Twin Pregnancies

Article by – Dr. Moe Thit Nay (Ayeyarwaddy Times, July 12) Carrying twins is a cause for great joy for a family, but it also presents a situation where increased medical care is needed for both the mother and the twin infants. We will explain the different ways twins are conceived, their types, and what needs to be known during twin births to enhance public understanding and knowledge. Dizygotic Twins (Two Fertilized Eggs) This is the most common type of twins. It occurs when two eggs are released from the mother's ovaries and are fertilized separately by two different sperm from the father. Even though the twins conceived together in the same womb, they may not look alike. They can be two boys, two girls, or a boy and a girl. Each twin has its own placenta and amniotic sac. Monozygotic Twins (One Fertilized Egg) This happens when a single egg is fertilized by a single sperm. Normally, only one fetus would develop. However, strangely, in the early stages shortly after fertilization, the fertilized egg splits into two, leading to the development of twins. These twins are genetically identical, so they look almost exactly alike. They will always be two boys or two girls, never a boy and a girl. Although they originate from one egg and one sperm, the structure of the placenta and amniotic sac differs depending on when the fertilized egg splits into two. Medically, monozygotic twins are further classified into four types based on this timing: 1. Dichorionic Diamniotic Twins Cell division occurs within 1 to 3 days after fertilization, allowing sufficient time for the placenta and amniotic sac to develop fully. Each baby has its own placenta and its own amniotic sac. Medically, this is the safest and most reassuring form of twin pregnancy, as there are no issues with placental blood flow competition between the twins. 2. Monochorionic Diamniotic Twins Cell division occurs between 4 and 8 days after fertilization. Both babies share a single placenta but have separate amniotic sacs. Medical studies show this is the most common form of twin pregnancy. Because they share one placenta, there can be an imbalance in blood flow to the two babies (Twin-to-Twin Transfusion Syndrome - TTTS), requiring close monitoring by a doctor via ultrasound throughout the pregnancy. 3. Monochorionic Monoamniotic Twins Cell division occurs late, between 8 and 13 days after fertilization. Both babies share a single placenta and live together in a single amniotic sac. Medically, this poses significant challenges and risks throughout the pregnancy, as the umbilical cords can become entangled. Close monitoring is essential. 4. Conjoined Twins Cell division occurs after 13 days post-fertilization. This late division means the fertilized egg does not split completely, and parts remain attached, resulting in twins born with connected bodies, such as joined chests, heads, or legs. Depending on the day of cell division, twins may share a single placenta (monochorionic) or live in a single amniotic sac (monoamniotic). In cases of monochorionic twins, there is a risk of TTTS, requiring close ultrasound monitoring by doctors. Women carrying twins have a significantly increased workload on their bodies compared to those carrying a single baby. Therefore, it is crucial to be aware of potential risk signs and manage the pregnancy systematically. Preterm Labor Approximately 60% of twin pregnancies result in preterm birth (before 37 weeks of gestation). This is because the uterus becomes too full to accommodate both babies. Pregnancy-Induced Hypertension and Preeclampsia Women with twin pregnancies are about twice as likely to develop pregnancy-induced hypertension and preeclampsia (a condition involving protein loss in the urine) compared to those with singleton pregnancies. Gestational Diabetes Increased pregnancy hormones produced by the placenta can lead to elevated blood sugar levels in the mother, requiring treatment for gestational diabetes. Anemia Both babies require a large amount of iron and folic acid for their development, which are supplied by the mother. This can lead to anemia. Furthermore, women with twin pregnancies tend to experience more weight gain, uterine pressure, back pain, leg swelling, and nausea compared to those with singleton pregnancies. Mode of Delivery for Twins Many people assume that twins must be delivered via Cesarean section. However, twin pregnancies can be delivered vaginally or by Cesarean section, and the chosen method depends on medical factors. Fetal Presentation If the first baby is in a cephalic (head-down) presentation, which is a normal position, a vaginal delivery can be attempted. After the first baby is born, the doctor will assess the position of the second baby and assist with delivery as needed. Indications for Cesarean Section If the first baby is in a transverse (sideways) or breech (bottom-down) presentation, or if both babies are breech, or if their positions are interfering with each other, labor may be prolonged, posing a risk to both the babies and the mother. To minimize risks to the mother and babies, a Cesarean section is the safest option. If the babies need to be delivered very prematurely (e.g., before 32 weeks of gestation), the baby's brain and body...