Twin Pregnancy: Answers from an Expert | Johns Hopkins Medicine
When you’re expecting twins, you know you’ll need two of everything for your registry. But what about staying healthy during your pregnancy? Do you need to double your food intake, weight gain and visits to the doctor? With regard to the babies, are there two placentas and two amniotic sacs, or can they share these?
While some twins may share a placenta and an amniotic sac, that is not the case for the vast majority of pregnancies. Here are three major possibilities that exist:
Two placentas and two amniotic sacs. A twin pregnancy with two placentas and two amniotic sacs is the optimal twin pregnancy, as each baby has its own nutritional source and protective membrane.
One placenta and two amniotic sacs. In pregnancies with one placenta and two amniotic sacs, you will definitely have identical twins. Additionally, when your babies share a placenta, there is a greater risk for complications, such as twin-to-twin transfusion syndrome. Your physician will closely monitor your pregnancy to check for potential problems.
One placenta and one amniotic sac. This is the riskiest and rarest type of twin pregnancy. Fetal complications can arise due to tangling of the umbilical cords or an imbalance in nutrients, blood or other vital life supporting systems.
Do I need to double my caloric intake during a twin pregnancy?
A common misconception surrounding twin pregnancy is that you need to double your caloric intake to provide your babies with enough nutrients. However, pregnancy nutrition guidelines aren’t simply based on the number of babies you’re carrying. Instead, they’re based on your body mass index at the time you became pregnant.
Your doctor will make individualized recommendations based on your starting weight. On average, it’s estimated that a woman’s caloric requirements will increase about 40 percent for a twin pregnancy. What’s most important, though, is that a woman eats as healthy as possible.
Do I need to take different prenatal vitamins for twins?
If you’re pregnant with twins, you should take the same prenatal vitamins you would take for any pregnancy, but your physician will recommend extra folic acid and iron. The additional folic acid and extra iron will help ward off iron-deficiency anemia, which is more common when you’re pregnant with multiples.
Will I need to visit my doctor more frequently?
While every pregnancy is different, most women carrying twins will have more frequent prenatal visits than women carrying only one baby. If your twins are sharing one placenta, you will automatically have a more frequent monitoring schedule.
If your pregnancy doesn’t have complications, your prenatal visits may not differ much from a singleton pregnancy until you get to the end of your second trimester. At that point, you’ll be seen more frequently because there is a higher risk of pre-eclampsia and preterm labor.
Do I have to see a maternal-fetal medicine specialist for a twin pregnancy?
Maternal-fetal medicine specialists see high-risk pregnancies, but not every twin pregnancy will fall into this category.
To find the best care provider for your twins, make sure that the physician is comfortable managing twins, including vaginal delivery of twins rather than only offering a cesarean section (C-section) for delivery.
Are all twin pregnancies delivered preterm?
A little more than half of twin pregnancies end in preterm delivery (before 37 weeks). While 40 weeks is the full gestation period of the average pregnancy, most twin pregnancies are delivered at approximately 36 weeks (range 32-38 weeks depending on the type of twin pregnancy).
Unfortunately, preventing preterm labor with multiples is more challenging than with a singleton pregnancy because the interventions used with singleton pregnancies are not as effective with multiples.
Can bed rest reduce the risk of preterm delivery?
Scientific data show that bed rest does not prevent preterm delivery. In fact, bed rest can increase your risk of developing blood clots and have negative financial and social consequences.
Although bed rest is not prescribed as frequently as it once was, your doctor may suggest reducing your activity level if you’re showing signs of early labor at the end of your second trimester or early in your third trimester.
Is labor and delivery significantly different with twins?
Labor is generally the same whether you’re having one baby or two. During delivery is when things differ significantly.
When it’s time to deliver your twins, you will go to an operating room even if you are delivering vaginally. This is a safety precaution known as a double setup. Following the vaginal delivery of the first baby, there is a small risk of an emergency cesarean section for the second baby. There is also the possibility of the second twin being delivered breech, which is a safe form of vaginal delivery if the obstetrician is experienced in this type of delivery.
Of women giving birth to twins over 32 weeks, only about 4 percent who try for a vaginal delivery will have a combined vaginal and cesarean section delivery. While it doesn’t happen very often, by delivering both babies in the operating room, physicians are better prepared to protect the health of the mother and the babies.
Although being pregnant with twins can seem very different, your doctor will treat your pregnancy like any other unless a complication occurs.
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Giving birth to twins | Pregnancy Birth and Baby
Twins are more likely to be born early, often before 38 weeks, so it's important to understand your birth options. Less than half of all twin pregnancies last beyond 37 weeks.
Because of the likelihood that your babies will be born early, there is a good chance one or both of them will spend some time in special care.
As twins are often born prematurely, it's a good idea to discuss birth options with your midwife or doctor early in your pregnancy.
You should also discuss where you would like to give birth. You will most likely be advised to give birth in a hospital because there's a higher chance of complications with a twin birth.
It's common for more medical staff to be involved in the birth of twins, such as a midwife, an obstetrician and two paediatricians - one for each baby.
While the process of labour is the same as when single babies are born, twin babies are more closely monitored. To do this, an electronic monitor and a scalp clip might be fitted on the first baby once your waters have broken. You will be given a drip in case it is needed later.
About one third of all twins are born vaginally and the process is similar to that of giving birth to a single baby. If you're planning a vaginal delivery, it's usually recommended that you have an epidural for pain relief. This is because, if there are problems, it's easier and quicker to assist the delivery when the mother already has good pain relief.
If the first twin is in a head down position (cephalic), it's usual to consider having a vaginal birth. However, there may be other medical reasons why this would not be possible. If you have had a previous caesarean section, it's usually not recommended you have a vaginal birth with twins.
If you have a vaginal birth, you may need an assisted birth, which is when a suction cup (ventouse) or forceps are used to help deliver the babies.
Once the first baby is born, the midwife or doctor will check the position of the second baby by feeling your abdomen and doing a vaginal examination. If the second baby is in a good position, the waters will be broken and this baby should be born soon after the first as the cervix is already fully dilated. If contractions stop after the first birth, hormones will be added to the drip to restart them.
You may choose to have an elective caesarean from the outset of your pregnancy, or your doctor may recommend a caesarean section later in the pregnancy as a result of potential complications. You’re nearly twice as likely to have a caesarean if you’re giving birth to twins than if you’re giving birth to a single baby.
The babies' position may determine whether they need to be delivered by caesarean section or not. If the presenting baby - the one that will be born first - is in a breech position (feet, knees or buttocks first), or if one twin is lying in a transverse position (with its body lying sideways), you will need to have a caesarean section.
Some conditions also mean you will need a caesarean section; for example if you have placenta praevia (a low-lying placenta) or if your twins share a placenta.
If you have previously had a very difficult delivery with a single baby, you may be advised to have a caesarean section with twins. Even if you plan a vaginal birth, you may end up having an emergency caesarean section.
This could be because:
one or both babies become distressed
the umbilical cord prolapses (falls into the birth canal ahead of the baby)
your blood pressure is going up
the labour is progressing too slowly
assisted delivery doesn't work
In very rare cases, you may deliver one twin vaginally and then require a caesarean section to deliver the second twin if it becomes distressed.
After the birth
After the birth, your midwife will examine the placenta to determine what type of twins you have. Twins can either be fraternal or identical.
If your babies need special care
Depending on where you plan to give birth, you may need to go to another hospital with appropriate facilities if complications in your pregnancy indicate you're likely to have an early delivery. This may not be near to home, so make sure to check there are enough beds for both your babies in the neonatal unit.
Ask if your chosen hospital has a transitional care unit or a special care nursery. These are places that allow mothers to care for their babies if they need special care but not intensive care. These hospitals are more likely to be able to keep you and your babies in the same place.
You might also want to ask if your hospital has cots that allow co-bedding (where your babies sleep in a single cot), if this is appropriate and if you want your babies to sleep together.
If you have one baby in the hospital and one at home, you will need to think about splitting your time between the two. When you visit your baby in hospital, ask if you can bring their twin and if co-bedding is allowed during visits.
If you want to breastfeed and only one twin can feed effectively, you may need to express milk to feed the twin who is having trouble feeding. You may then need to put the twin who can feed on the breast to encourage milk production in order to get enough milk to feed both babies.
Check if your hospital offers support from a community neonatal nurse, which would allow for you and your babies to leave hospital earlier, for example if your baby is still tube-fed.
When you go to clinics for follow-up appointments, it's a good idea to ask not to be booked into early morning appointments. Getting out of the house with two babies, particularly if one is unwell, can be difficult.
For more information and support, visit Twins Research Australia.
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Preparing for the birth of twins
The news of a multiple pregnancy often throws future parents into a small (or big) shock. Even if the pregnancy was planned and expected, you still need to get used to the idea that you will return from the hospital with two babies, and not with one. Get used to and start preparing for a joyful event, based on new circumstances.
Features of multiple pregnancy
Before the first ultrasound, you might not have suspected that two hearts were beating inside at once. But now that this has been clarified, the doctor will take you under special control: be prepared for the fact that you will have to visit the antenatal clinic more often than you planned.
In the case of multiple pregnancies, it can manifest itself more strongly and for a longer time. Toxicosis can disturb the expectant mother not only in the early stages, but sometimes in the later ones. Strange taste preferences may be more pronounced. Such unpleasant manifestations as digestive problems and constipation are also more common in multiple pregnancies.
Be sure to follow your doctor's recommendations for nutrition and diet. Eat a varied diet and choose healthy foods. Now you need more vitamins and minerals. But DO NOT OVEREAT either. During pregnancy with twins, weight gain will be more than with one child. Excess weight is a burden on the whole body as a whole, and on the heart in particular. So try to gain kilograms within the normal range.
It will appear earlier and will increase faster than during pregnancy with one baby. Get ready to need the special maternity clothes sooner than you think. Be sure to wear a bandage when your belly is big enough.
In case of multiple pregnancy, childbirth usually occurs . If the approximate terms of delivery with one baby are 39-40 weeks, then during pregnancy with twins they happen at about 35-37 weeks. This does not mean that you will definitely have it - twins are born later than this period - but it is still worth preparing mentally (and financially) for an earlier birth.
4. Preparing for childbirth and returning from the hospital
Preparing your home for the reception of new residents - also plan all these things for an earlier date. If you want to participate in this in person, then plan to do so by around week 20. Later, it will be just physically difficult for you to do all this.
A double burden on a woman's body, the likelihood of premature birth - a mother of twins should take care of herself and have more rest. For the health and well-being of babies, it is very important to develop before the due date in the mother's tummy. And your primary task is to remain a happy pregnant woman for as long as possible. If possible, go EARLY ON Maternity Leave. Before the expected maternity leave, you can take another regular leave or leave at your own expense.
We organize life with two babies
Even with one baby, the first year is not easy for a mother. Her every day is a cycle of the same things: washing-cleaning-ironing-cooking. It is good if someone can help you with the children and around the house. But besides the “live”, there are also all kinds of mechanical helpers in everyday life (glory to progress). Of course, they cost money and will take up space in the house, but they will save you a lot of time and effort.
1. Household helpers
- multicooker . It is convenient to cook diet meals for a nursing mother, and later for babies who receive complementary foods. It is also a big plus that it can keep dishes hot for a long time;
- thermopot . Especially useful for diluting baby food;
- dishwasher .
With the advent of children, you will have more of it at times. Along with the actual washing machine, a dryer will also come in handy. You will not need to hang up and remove a bunch of wet laundry, but just shift from one machine to another. And many things, if taken out immediately after the completion of a certain program, do not need to be ironed.
You can attract numerous relatives who are eager to give something for the birth of babies to buy these helpers.
Two babies at once exclusively breastfed - this, of course, is not easy, but as practice shows, it is quite feasible. To make the process as comfortable as possible, there are special underwear and comfortable clothes for breastfeeding for nursing mothers.
Also, when feeding two children at the same time, a special pillow for feeding twins is useful. It allows you to place the kids in the most convenient way. And mom's back will not strain and get tired.
In any case, every mother understands that no mixture can replace everything that breast milk gives the child, so it is worth making every effort to establish lactation and feed two babies at once. If there are difficulties with this, in our time of available information, you can always seek help and advice in this matter from experienced mothers who have had experience in feeding twins, or from specialist breastfeeding consultants.
A sling can be an indispensable help for a mother of twins. It will be useful to you both at home and on a walk. The temperament and regimen of babies can differ significantly: while one lies calmly or sleeps in a crib, the second requires mother's hands. At home, a sling can be used for motion sickness, feeding, or simply to carry a naughty baby.
Walking with a stroller for twins is a separate “song”. Even with an ordinary stroller, it is not always convenient for a mother to walk and drive everywhere, to say nothing of a larger design. With a stroller for twins, you need wide doors and ramps, a freight elevator in the house and enough space in the apartment for storage. Not to mention the fact that such a stroller also has an impressive weight.
An excellent option for walking can be a tandem of a regular stroller and a sling. Again, while one baby is sleeping peacefully in the stroller, the second can be awake or receive a portion of mother's milk in a sling.
Both babies can be worn in the sling at the same time . This will require more experience and skill from the mother, but it will also allow her to be more mobile.
Despite all the everyday difficulties, the birth of twins is a double happiness. Undoubtedly, you will have a difficult period before the kids become large enough and independent. But all these difficulties will block the joyful and amazing moments of your communication with children.
Twin birth: natural or caesarean section
Why do multiple pregnancies and twin births happen?
Features of pregnancy by identical twins depending on the time of separation of the zygote.
Can a woman have twins in her first birth?
How often do twin births occur?
How long does a twin birth take?
When is the due date for multiple pregnancies?
Which is better for twins - caesarean section or natural childbirth?
The human reproductive system is very economical, and usually a woman becomes the mother of one baby. However, occasionally we come across parents walking with a double stroller or trying to fit two identical toddlers into a car. Why is this happening? What is the probability of becoming a mother of twins? What awaits a woman when the time comes for twins to be born - caesarean section or natural childbirth? We answer your questions.
Why do multiple pregnancies and twin births happen?
Sometimes two or even more babies begin to grow in the womb of a future mother at once. If you do not consider unique and very rare cases, then twins can be homozygous (identical, emerging from the same egg) and heterozygous (fraternal, grown from different eggs).
Heterozygous twins appear when several eggs mature in a woman at the same time. Babies are always isolated - each of them has an individual placenta and fetal (amniotic) bladder. They may have different sexes, and, in general, they usually resemble each other no more than the children of this couple, born several years apart from different pregnancies. At the same time, eggs can be fertilized both as a result of one sexual intercourse, and different - with an interval of several hours or days.
If a woman has a very active sex life, it is even possible that one egg is fertilized by the sperm of one partner, and the second by the other. Then, during the birth of twins, babies are born, each of which has its own father, which in scientific language is called the term "superfecundation". The exact frequency of this phenomenon is unknown, but in cases where DNA examinations were performed when paternity was disputed (in other words, when potential dads suspected in advance that the matter was unclean), superfecundation was confirmed in 2.4% of twin pairs 1 .
Monozygotic twins are a different story. At first, everything happens as usual: one egg comes out of the follicle during ovulation, it is fertilized by one sperm, it becomes one zygote (a cell with the combined genetic material of the parents), from which one embryo should develop. But after a while, it suddenly splits into two identical copies. One of them can divide again, and then instead of giving birth to twins, the mother will give birth to triplets, if both zygotes do this, there will be four twins.
Features of pregnancy by identical twins depending on the time of separation of the zygote.
If fraternal twins always have separate "apartments" - each has its own placenta and amniotic bladder, in identical twins it depends on the time of separation 2 .
Day of separation of the zygote
Percentage of cases
Each baby has its own placenta and amniotic sac, just like fraternal ones.
Twins share a common placenta but amniotic sacs are separated.
Twins share one amniotic sac and feed on a common placenta.
Siamese twins appear late in separation. Contrary to the common misconception, they do not grow together, but, on the contrary, do not have time to separate.
Can a woman have twins in her first birth?
Everything is possible. Do you remember that multiple pregnancies can be identical and heterozygous? The likelihood of developing identical twins is the same for all women. In both first and subsequent births, twins of identical babies are born in about 4 out of 1000 pregnancies 3 .
Fraternal twins appear for a different reason - due to hyperovulation, i.e. maturation of two or more eggs in one cycle. This is influenced by the following factors 4 :
Use of fertility drugs.
Recent withdrawal of hormonal contraceptives or irregular use of contraceptives.
Obesity, i.e. body mass index above 305.
Genetic predisposition. If you yourself have a twin, if your mother or your sister gave birth to twins, your chances are higher than the average natural probability of giving birth to twins 6 .
Rost. Tall women are more likely to become mothers of fraternal twins.
Woman's age. The likelihood of multiple pregnancy increases after age 35 7 .
How often do twins occur?
In obstetrics, there is the so-called Hellin's law 8 , which states that the probability of having twins, triplets, etc. obeys the following formula: 1/89N-1, where N is the number of twins.
Number of fruits
1 out of 89 genera
1 out of 7,921 births
1 out of more than 700 thousand births
Hellin's law is just a curious observation made by a late 19th century physician, and modern science offers much more complex formulas. However, sometimes it works amazingly. For example, in 2016 in Russia there were 1,876,646 births, in which 22,144 twins and 408 triplets were born 9 , which in percentage terms is 1.18% and 0.021%. Not bad accuracy!
In general, the statistics of twin births in our country looks like this:
Percentage of twin births among all births in Russia from 1996 to 2016 9 .
It is easy to see that in the late 90s and early 2000s, the statistics were almost constant, and then unexpectedly, but surely, they crept up. The answer is simple: medicinal and other assisted reproductive technologies have been actively developing lately, and they often lead to multiple pregnancies 10 . So the last numbers are naturally occurring twins plus the contribution of infertility treatments.
How long does it take to give birth to twins?
Doctors distinguish three stages in childbirth - the period of disclosure, the period of exile and the subsequent period. The first period begins with contractions and ends with the full opening of the cervix, the third starts after the birth of the baby and ends with the appearance of the afterbirth - the placenta and the remains of the membranes. The duration of these periods depends more on the individual characteristics of the body than on how many babies the woman bore.
Of greatest interest is the period of exile - the very one when babies from a cozy mother's womb are "expelled" into our difficult world. They come out sequentially, which means that we can assume that the birth of twins is longer for this particular interval between the appearance of the first and second child. So how much does he make?
Thanks to doctors from the Hesse region in Germany, this question has a very precise answer. For 15 years, they carefully researched information about natural births of twins in local hospitals. As a result, an impressive amount of data was collected - more than 4,000 cases of multiple pregnancies, as a result of which more than 8,000 babies were born. The analysis of this array made it possible to calculate the most probable interval that passes between the birth of babies in twin births in a natural way. For 3 out of 4 mothers, this takes no more than 15 minutes, and on average, one twin is only 13.5 minutes older than the other 11 .
Interval between births of twins, minutes
Up to 15
Rarely in obstetric practice, surprising cases are noted when a much longer time elapses between the birth of twins. Apparently, the first position among the record holders for the duration of the birth of twins is occupied by a resident of the German city of Cologne named Oksana (we will not say, but the name suggests that she may be our former compatriot).
On November 17, 2018, at the 26th week of pregnancy, a woman went into premature labor. She gave birth to a live premature baby girl weighing 900 grams, after which the cervix closed and the contractions stopped. The doctors decided to give the second child the opportunity to stay in the mother's womb as long as possible. As a result, another girl was born four days after the planned date - 97 days later than her sister and already in 2019 12 . By the way, don't worry about the older baby: the doctors took her out, and after a three-month separation, the twins met again.
When is the due date for multiple pregnancies?
Pregnancy in a woman expecting several babies at once is usually shorter. Twins can be expected as early as week 35, triplets at week 33, and four twins starting at week 29 13 . After the birth of twins, doctors surround newborns with special care. And the birth of three or more babies requires the closest attention, because such twins in the vast majority of cases are born prematurely.
A woman who has several children has a significantly higher chance of becoming a mother ahead of schedule. Doctors will try to do everything to prolong the pregnancy as much as possible, but the woman herself should not risk the future of her babies either. At the very least, she needs to monitor her diet and health, breathe fresh air, avoid psychological stress and excessive physical exertion.
What is better for twins - caesarean section or vaginal delivery?
The final decision on the tactics of childbirth is made by the specialists of the maternity hospital, guided by all the information available to them about the pregnancy. However, practice shows that if everything goes on the whole normally (the gestational age by the time of delivery exceeds 32 weeks, and the first twin is settled in head presentation, i.e. is going to go head first), there is no significant difference between the natural birth of twins and caesarean section 14 . A large study involving 106 medical centers in 25 countries showed that the risk to babies remains the same with both modes of delivery.
Cesarean section is indicated for breech presentation of the first twin in twin birth. However, in this situation, the operation is recommended even during pregnancy with one baby. If the twins are growing up in a common amniotic sac, doctors also usually opt for a caesarean section. In other cases, you should not be afraid of giving birth to twins in a natural way - they are no more dangerous than surgery 14 .
Links to sources:
Wenk, R. E.; Houtz, T; Brooks, M; Chiafari, F. A. (1992). How frequent is heteropaternal superfecundation? Acta geneticae medicae et gemellologiae. 41(1):43–7.
Curran, Mark (2005-11-02). twinning. Focus Information Technology.
Professor Hanan Hamamy. GFMER. Monozygotic twinning.
Joel Forman, MD. Causes of Identical and Fraternal Twins.
WebMD. Moms' Obesity Makes Twins More Likely.
U.S. National Library of Medicine. Is the probability of having twins determined by genetics?
ACOG. Multiple Pregnancy.
Johan Fellman (November 5th 2018). Historical Studies of Hellin's Law, Multiple Pregnancy - New Challenges, Julio Elito Jr., IntechOpen.
Federal State Statistics Service (Rosstat). Demographic Yearbook of Russia. 2017: Stat. Sat / Rosstat. - M., 2017. - 263 p. ISBN 978-5-89476-447-4.
Kulkarni AD, Jamieson DJ, Jones HW, Kissin DM, Gallo MF, Macaluso M, Adashi EY (2013). Fertility Treatments and Multiple Births in the United States. New England Journal of Medicine. 369(23): 2218–2225.
Stein W, Misselwitz B, Schmidt S (2008). "Twin-to-twin delivery time interval: influencing factors and effect on short-term outcome of the second twin".