What is a Multiple Pregnancy?

A multiple pregnancy is defined as expecting more than one child at once. For example, twins are two infants that a woman is carrying at the same time and triplets are three children delivered inside one pregnancy. Additionally, one can carry numerous infants at once (high-order multiples). Multiple pregnancy often carries more risks and complications than a singleton pregnancy (carrying just one baby). 

What are Twins?

Twins are defined as two children produced in the same pregnancy. Due to an increase in the use of reproductive medications and treatments like IVF, multiple births have become more prevalent recently.

How are Twins conceived? How are Twins made?

Two key factors can lead to a multiple pregnancy:

• two or more independent eggs are fertilized by different sperm at the same time
• one fertilized egg is split before it implants in the uterine lining.

These two various kinds of multiple pregnancies result in siblings that are either identical or fraternal. The distinction between identical and fraternal twins is linked to the process of repeated pregnancies. When a single egg is fertilized before splitting later, identical twins or triplets result. These freshly split embryos are all the same. Children with identical multiples have the same sex and appearance.

Multiples that are fraternal are created from separate eggs that are fertilized by various sperm. The genetic material is diverse since these are unique eggs and unique sperm. These kids won't all have the same appearance, and they can be of different sexes.

In cases of expecting triplets or more, the children may be all identical, all fraternal, or a combination of the two. The body may release several eggs, and if more than one of them are fertilized, this may occur. When a woman has several fertilized eggs and at least one of those eggs divide after fertilization, she has both identical and fraternal multiples. 

What are the Signs of a Multiple Pregnancy? 

A prenatal ultrasound examination with the doctor is the only way to determine if a woman is carrying more than one baby. A medical professional can verify the number of babies inside the uterus during this exam by looking at pictures of the interior.

A multiple pregnancy could result in more severe symptoms than a single pregnancy. Twins early pregnancy symptoms may include:

• Nausea and vomiting (morning sickness) may be experienced.
• The body weight increases more rapidly during the first trimester of pregnancy with twins.
• The breasts may feel unusually tender or sore.
• While having twins hCG levels increase. Human chorionic gonadotrophin, abbreviated as hCG is a hormone produced during pregnancy, representing what pregnancy tests are designed to detect. 
• The amount of protein alpha-fetoprotein in the human blood also increases while having a multiple pregnancy.

Specialists may suspect multiples in addition to an ultrasound if a fetal Doppler scan reveals more than one heartbeat.

What increases the chances of multiple pregnancies? 

The likelihood of having numerous children can be impacted by various factors. A woman could be more likely to become pregnant and have multiple children consecutively if she:

• Is older- once a woman gets older, her body starts releasing multiple eggs at a time.
• Is a twin herself or have twins in the family? So, can twins have twins?

Genetics is also another risk factor for numerous pregnancies. If a woman is a multiple herself or if multiples run in her family, the risk of becoming pregnant with multiples is higher. This genetic feature typically runs in the mother's (maternal) side of the family.

• Uses fertility drugs. The use of reproductive drugs is another factor that could lead to numerous pregnancies. Techniques like in vitro fertilization (IVF), which occasionally involves implanting more than one fertilized egg in the womb, can increase the risk of becoming pregnant more than once. Medical professionals will often transfer more than one egg at once to increase the chances of a successful pregnancy. 
• If one is heavier or taller than usual, they may also be at a higher risk of having multiple pregnancies.

What are some complications and risks linked to having twins/ multiple births?

Difficulties during pregnancy can affect anyone, no matter how many babies a woman is carrying. However, the majority of medical professionals believe that repeated pregnancies are riskier than single pregnancies. This does not imply that all women who carry many pregnancies will experience difficulties. If one is expecting multiples, the healthcare practitioner will want to keep an eye on them for any potential issues that could arise from carrying multiples at once. Each risk factor will be discussed with the mother by the doctor, who will also periodically check in with her to make sure nothing alarming is happening. Possible complications are:

• Premature labor and premature birth

Premature labor is the most typical complication of multiple deliveries. Multiples-pregnant women are more likely than single-baby mothers to experience premature labor (before 37 weeks). Many multiples mothers set a goal of finishing 37 weeks. Reaching this week of gestation, which is considered term in twin pregnancies, enhances the likelihood that the infants will be born healthy and at a good weight. Low birth weight is another issue of multiple births that can affect prematurely born babies.

• Preeclampsia/ gestational hypertension

Hypertension refers to high blood pressure. A healthcare practitioner will closely monitor the blood pressure throughout pregnancy to ensure that the mother doesn't develop gestational high blood pressure. Preeclampsia is a risky condition that can result from this. Compared to women expecting a single child, women carrying multiples experience complications from high blood pressure twice as frequently. Additionally, this issue tends to affect multiple pregnancies more severely than single pregnancies and occurs earlier in pregnancy.

• Gestational diabetes

Diabetes can also manifest during pregnancy. The placenta's increased hormone production is the reason of this. The placenta's size may also play a role in this disorder. Insulin resistance is exacerbated if one has two placentas.

• Placenta abruption

This syndrome develops when the placenta separates from the uterine wall prior to delivery. There is an emergency here. Women who are expecting multiples are more likely to experience placenta abruption.

• Fetal growth restriction 

This disorder is also known as small for gestational age (SGA) or intrauterine growth restriction (IUGR). When one or more of the infants are not developing at the appropriate rate, this problem develops. The babies could be born early or with low birth weight as a result of this disorder. This issue arises in over half of multi-baby pregnancies.

There are usually two placentas for fraternal twins. The risks of fraternal twin pregnancies are comparable to those of single-baby pregnancies. However, compared to pregnancies with one child, more issues could occur.

One placenta makes up 70% of cases for identical twins, although it can also make up both placentas (30 percent of the cases). Similar dangers exist for identical twins carrying two placentas as for fraternal twins. Risks specific to identical twins with one placenta (referred to as monochorionics) exist. They may develop a disorder known as twin-twin-transfusion-syndrome in 5 to 15% of instances (TTTS). This is the result of the twins' vascular connections at the placenta level. The twins might have blood in common as a result of these communications. If nothing is done, there is a 90% chance that the twins will pass away in utero when this occurs. In-utero procedures are carried out to lower the twins' chance of fetal death.

Twin-anemia-polycythemia sequence is another issue that can occur in identical twins with one placenta (TAPS). This is because of vascular contacts at the placental level, which allow blood to flow from one twin to the co-twin. One twin experiences anemia (few red blood cells) in this disease, while the other twin experiences polycythemic anemia (too many red blood cells). When this occurs, numerous treatments and interventions are carried out.

Selective IUGR is another condition that can affect identical twins with a single placenta. While the co-twin does not experience much growth, one twin does.

Twin-reversed-arterial-perfusion syndrome is a different disorder that is common in identical twins. In this circumstance, one twin's heart pumps blood for the circulation of the other twin. The heart of one twin prevents it from surviving after delivery. The twin with a healthy heart's result differs. Thankfully, this syndrome is uncommon (1 in 20,000 to 40,000) and treatable in utero.

The same sac may also contain identical twins carrying the same placenta. They are referred to as monoamniotic-monochorionic (one placenta) (one gestational sac). This pregnancy occurs in 1% of multiple gestations and is linked to a higher probability of having one or both sets of twins.

Medical professionals use ultrasound in order to identify all the health complications and risks mentioned above. 

Twins Ultrasound

The imaging technique of diagnostic ultrasound, also known as sonography or diagnostic medical sonography, uses sound waves to generate images of the internal organs and other structures in the human body. A variety of diseases and ailments can be diagnosed, and treatment can be planned using photos. While certain ultrasound exams require inserting a tiny device into the body, most ultrasound examinations use ultrasound equipment that is outside of it.

The only method to confirm that one is expecting twins is via an ultrasound scan. The earliest they'll probably find this out is between 10 and 14 weeks after the dating scan. Diagnoses of twins can be made with ultrasound nearly without error. It becomes more difficult to determine how many babies a woman is expecting in cases of carrying more than two. The babies can be difficult to distinguish for the sonographer. The accuracy of the due date mostly depends on the results of the dating scan. An ultrasound scan is typically offered at around six weeks if the woman is pregnant as a consequence of fertility therapy to ensure everything is fine.

Twins 4 week ultrasound

Blastocysts will implant in the uterine wall during week 4 of a twin pregnancy, develop into embryos, and start to build their body parts. To support the unborn children, placentas, amniotic sacs, and yolk sacs will also be developing at this time.

At four weeks, twin pregnancy symptoms are identical to those of a regular pregnancy. The mother might already be displaying extremely early pregnancy symptoms, but it is important to remember that some women don't. If present at all, several symptoms, such as nausea and breast soreness, may be more severe in a twin pregnancy than in a single pregnancy. Though it's safe to say that not all women experience this, some women have spoken of "just knowing" or "having a sense" that they are carrying twins. Even while severe symptoms and intuition could be indicators of twin pregnancy, an ultrasound performed later on is the only way to be certain. Some significant changes take place at roughly the 4-week mark of pregnancy, including implantation. At this point, implantation bleeding, one of the early signs of pregnancy, may become apparent.

Twins 5,6,7,8 week ultrasound

Whether expecting a singleton or twins, 5 to 8 weeks pregnant is when nausea and vomiting, sometimes known as morning sickness, may start. Human chorionic gonadotropin (hCG), a hormone that is produced during pregnancy, may be a contributing factor even if the exact cause or causes of this illness are unknown. Although no one enjoys experiencing this uncomfortable symptom, which can sometimes be more intense when carrying twins, many expectant mothers prefer to view it as a positive sign that their pregnancy is progressing well. 

The brains and spinal cords of the twins begin to develop. The infants' spinal cords and brains will form from the neural tubes at around six weeks and little legs and limbs begin to appear. The twins will grow paddle-like buds for limbs around the eighth week of the pregnancy. At this point, the tissues that will eventually make up the babies’ hearts will start to form. During this trimester, healthcare professionals may even do an ultrasound exam during which heartbeats can be heard. Additionally, the primary organs begin to develop. All of the babies’ major organs will have begun to mature by the end of the eighth week.

Twins 9 to 12 week ultrasound 

One might be surprised to learn what's happening to the baby bump as the mother approaches the last weeks of the first trimester. Nails, fingers, and toes start to form. By 12 weeks, fingernails will also start to sprout. By this time, the little one will also begin to develop little toes. Changes also occur to facial characteristics, as the twins’ faces become more distinct and less rounded at twelve weeks. The lips, noses and eyes, as well as eyelids are formed during this time. Tooth buds appear under the gums, so the future teeth are already in place.

The second trimester of twins pregnancy 

When twin pregnancies are monitored week by week, the symptoms aren't all that dissimilar from singleton pregnancies. The second trimester is when it will become increasingly clear that one is expecting twins because twin moms typically start to show their bumps. The body is a nutritious home for two developing babies, meaning that it is normal for the mother to experience greater discomfort, fatigue or weight gain than singleton parents.

The third trimester of twins pregnancy

Backaches and swelling in your hands, feet, and legs are two of the most typical twin or singleton pregnancy symptoms that may develop week by week in the third trimester. One might consequently have trouble walking or sleeping comfortably. The twins are preparing for the big day in the meantime. They're listening to familiar sounds like voices during this period, and they're probably settling into the best position for a vaginal birth, which is for both infants to have their heads down. Sometimes only one twin will be facing headfirst, and other times both twins will. There is a larger chance of needing a cesarean delivery or giving birth too soon when having twins.

Twins FAQ

• Are identical twins the same sex?

Identical twins or triplets are always the same sex because they share the same genetic material. The specific sperm cell that fertilizes the egg during conception determines the baby's sex. Sperm cells come in two varieties: those with an X chromosome and those with a Y chromosome. An X chromosome can be found in the mother's egg. An XX combination will result from fertilization of the egg by a sperm cell with an X chromosome (female). There is an XY pairing if the sperm cell contains a Y chromosome (male). Whatever chromosomal combination is present during fertilization determines the sex of all multiples since identical multiples begin as one egg and later split.

• Twins vs twins with down syndrome

According to multiple sources, about two out of every 1,000 pregnancies for twins will result in at least one child with Down syndrome. The likelihood that a pregnancy will result in twins and that both of the twins will have Down syndrome, on the other hand, is approximately one in 1 to 5 million before conception.

• Staying healthy for twins pregnancy

For any pregnant woman, it's crucial to eat a balanced diet, get enough sleep, and see their doctor frequently in order to have a successful pregnancy. These actions are especially crucial when having twins or any other multiple pregnancy.

If expecting more than one child, the mother is advised to adjust her diet. It's crucial to consume adequate protein and drinks in order to stay hydrated. Additionally, she must ensure that she consumes enough extra calories for the growing fetuses. One general guideline is to consume an additional 300 calories per baby each day. This indicates that one will need to increase their daily calorie intake by 600 if expecting twins. The diet and the precise amounts one will need for a healthy pregnancy should be discussed with a healthcare professional. To lessen the difficulties of the pregnancy, it is essential for the mother to take good care of herself and rest.

For twins pregnancy the mother may want to locate a medical professional with knowledge and experience regarding multiple births. She and the unborn child can both benefit from specialized healthcare if the highest quality of treatment is desired. In multiple pregnancies, the necessity for frequent and more intense prenatal care is essential.

Moreover, while having twins daily movement and physical exercise are recommended. Low-impact workouts are a fantastic way to stay healthy and fit throughout pregnancy (swimming, walking, prenatal yoga). However, the ideal activities during pregnancy should be discussed with a medical professional, as some activities may not be recommended (for example, jogging and exercises that require jumping). 

Conclusion 

Multiples are infants that develop in the uterus of a woman at the same time. They occasionally have the same appearance — identical — and occasionally have the same appearance as usual siblings — fraternal. There are many ways this phenomenon can happen. The most common key factors linked to a twin pregnancy are more than two independent eggs being fertilized by different sperm at the same time and a fertilized egg splitting before its implantation in the uterine lining.

As multiple pregnancies and births may have more risks and complications than single pregnancies, it is essential to acknowledge and fully understand what being pregnant with twins implies, including the signs and early pregnancy symptoms, health complications and how the overall pregnancy normally looks like. Consulting a medical professional regarding any experienced issues during twin pregnancy is crucial, as many severe complications may occur. The mother should take good care of herself, get enough rest and be physically active, as well as make sure that she gets enough nutrients for herself and the two developing babies.