Illustration: Olivia Mew
Finding out that you’re pregnant is one of the great joys of life. Being pregnant with twins is double the joy (and sometimes double the unpleasantness, too). Twin pregnancy is very different from being pregnant with one baby. Here’s what you need to know.
Eating for three (not really) You might think that being pregnant with twins means eating for three. Sadly, that isn’t the case. Whether you’re carrying one baby (or singleton, in doctor-speak) or twins, the amount of weight you should gain depends on your pre-pregnancy body mass index (BMI). If your BMI is in the healthy range (18.5 to 24.9), the recommended weight gain for a singleton is between 20 and 35 pounds. And though there are no set guidelines for twins, between 30 and 50 pounds is average, says Ellen Giesbrecht, senior medical director of the maternal program at BC Women’s Hospital in Vancouver. “It’s double the placenta, the baby, the fluid and the additional body resources to supplement that pregnancy,” she says.
Gaining enough weight is important (it’s been shown to help ward off preterm labour), but it only takes an extra 200 to 400 calories each day (versus 150 to 250 calories for one baby) to hit your target—the equivalent of a bowl of yogurt and some fruit every day.
So sick, so tired That is, of course, assuming you can eat because twin morning sickness laughs in the face of regular morning sickness. “The so-called minor symptoms of pregnancy, which almost everybody gets in a pregnancy with a singleton, aren’t as minor with a twin pregnancy,” explains Jon Barrett, a specialist in maternal-fetal medicine at Sunnybrook Health Sciences Centre in Toronto and a leading expert on multiple births.
Hormones such as human chorionic gonadotropin (hCG), progesterone, relaxin and estrogen are thought to be the main culprits in backaches and other unpleasant muscular symptoms. Those hormones also make you feel as though you are going to puke all the time, give you the urge to pee constantly and cause acid reflux from hell. Two babies means way more hormones—not necessarily twice as much but enough that these symptoms are often considerably worse, start sooner (like, right away) and last longer. If you truly feel awful and are having difficulty eating or keeping anything down, speak to your healthcare provider.
Your belly is going to get really, really big While women with singleton pregnancies can sometimes hide their baby bumps well into their second trimesters, twin moms might find themselves having to pull on the stretchy-panel maternity pants between eight and 12 weeks. This is especially true if previous children have already taught your abs how to make like Elsa and “let it go.” How big will you get? There’s no way to predict and every woman is different, but measuring weeks ahead and looking like you’re ready to pop at six months along isn’t uncommon. By the time I hit 32 weeks, I was down to one super-stretchy shirt that could still cover my belly. Otherwise, I was flashing midriff like a ’90s pop star.
We like to move it, but we can’t With singletons, mobility generally doesn’t become difficult until the third trimester, but the sheer bulk of a twin pregnancy means that simple tasks (like bending over or getting off the couch) may become next to impossible in the second trimester.
The added weight of carrying twins and loosey-goosey ligaments caused by the hormone relaxin often lead to big-time backache, whether you’re standing up or lying down. Having to physically support your belly when you turn over in bed doesn’t help either. Barrett says to enlist lots of pillows to prop up your bump (OK, more like personal mountain) and find a comfortable side-sleeping position. You’ll still wake up multiple times a night to rearrange the pillows, but chances are, you’re going to have to pee—again—anyway.
Keeping active can help with sleep and backaches, but you’ll have to temper your expectations, even if you’re super-sporty. “Because you’ll get tired faster and carry more weight, you’re not going to be the woman who is running a 10K right up until the end of her pregnancy,” says Giesbrecht.
Scans, scans, and more scans Clinical guidelines recommend that all women have an ultrasound between 10 and 13 weeks and another between 18 and 22 weeks to confirm gestational age, check for development and screen for abnormalities. With normally developing singletons, that’s it for scans because external measurements are used to gauge baby’s growth. The only way to track growth with twins is through regular ultrasounds, so instead of having two, twin moms get to see their beans on screen every two to four weeks, with monozygotic twins (those who developed from one egg) often requiring more frequent scans than dizygotic (two babies resulting from two separate eggs). You may also have transvaginal scans (where an ultrasound wand is inserted into the vagina) to assess the thickness of your cervix, which can be an early indicator of preterm labour. After 30 weeks, you can expect to see your doctor and your sonographer (and by then, you will know every wand-wielding ultrasound wizard in the clinic by name) once a week until your babies arrive.
Higher risk of complications for the babies In addition to growth, your healthcare provider is also using the ultrasound at 19 weeks to look for abnormalities in development, which are more common with multiples. “It’s not that each baby is at increased risk; each baby is at the same risk as a singleton,” says Barrett. “But, because there are two babies, there’s twice the risk of chromosomal abnormalities.” The most common genetic abnormality is Down syndrome, but the scans and routine pregnancy bloodwork will also check for other genetic abnormalities, such as Trisomy 18, and physical abnormalities, including neural tube defects. There’s no increase in the likelihood of structural problems with dichorioinic twins (fraternal twins with separate placentas). However, monochorionic twins (twins who share the same placenta) are more likely to have issues like cardiac and neurological defects, and monozygotic-monochorionic twins (who share a placenta) have a 10 to 15 percent chance of developing twin to twin transfusion syndrome (TTTS), an imbalance in blood flow between the babies. Your doctor and a genetic counsellor will inform you about these risks and their possible outcomes.
More risks for Mom, too All twin pregnancies are considered high risk, regardless of how old you are or what kind of shape you’re in (though both age and general health can have an effect). Twin moms face the same potential complications as singleton moms, but many of them are either more likely to happen or more serious. Some complications, like iron deficiency and anemia, are almost universal for twin moms but easily treatable with supplements. More-serious issues, such as placental problems, are more common because of the added pressure and weight of carrying two babies. You’re also two to three times as likely to develop gestational diabetes. There is also a greater risk of developing hypertension (high blood pressure), which can sometimes lead to pre-eclampsia, a rapid and dangerous rise in blood pressure.
You’ll probably go into labour early More than half of all twins in Canada are preterm (born before 37 weeks). While bed rest is losing favour as a treatment for preterm labour, your healthcare provider will recommend that you take it easy, including taking leave from work several weeks before the babies are due.
Full-term babies will still probably be born before 40 weeks, but that’s OK, says Giesbrecht. “We recommend delivery for all patients by 38 weeks with twins,” she says. “There is no proven benefit for the babies in a twin pregnancy being in utero beyond 38 weeks that offsets the increased risks of complications and adverse events for mothers and babies.”
You’re going to need tiny onesies Though there’s no guarantee, it’s likely that your twins will be on the smaller side. “They’re still on a normal singleton growth curve, but they tend to be on the lower end rather than the higher end of average,” says Giesbrecht. The average weight for a twin born in Canada is around 5.5 pounds (2,500 grams). If they’re born earlier than 37 weeks, they may have a lower birth weight. While the majority of late-preterm twins (those born after 32 weeks) experience no long-term complications, they are more likely to end up in the neonatal intensive care unit (NICU) with breathing, heart and developmental issues.
Your healthcare provider options are more limited There are midwives and family doctors who will happily take on a patient expecting twins, but the high-risk nature of multiple births means that you’re probably going to have to see an obstetrician at some point, even if it’s only in consultation or through a shared-care approach.
You’re more likely to have a Caesarean delivery or other intervention The rate of C-sections for singleton pregnancies has remained fairly constant over the past few years, at around 30 percent. For twins, the rate is almost double, though a large-scale study led by Barrett shows that planned Caesarean sections for twin births have no benefits in terms of maternal and fetal outcomes.
Drug-free birth? Probably not If you have your heart set on a drug-free delivery, you might be able to, depending on your individual circumstances and your healthcare provider’s stance. But the increased likelihood of needing a C-section or other assistance, such as forceps and vacuum extraction, is why most OB-GYNs strongly caution their twin-mom patients against trying for a drug-free birth.
“Very often, you have to get the second baby out quickly because the placenta starts to separate,” explains Barrett. “Having the epidural in place really facilitates that because you can put your hand in and do a breech delivery, extraction or whatever you need to do to get that second baby out quickly.” In rare cases (two to four percent) when the first baby has been delivered vaginally but a D-section is required for the second, having the epidural in place is vital to ensure that the second twin is delivered before further complications arise. “If you don’t have an epidural in place, the only option is to give an emergency general anaesthetic, and that’s very dangerous for the baby and the mother,” explains Barrett. “We can do it if we have to and we can do it safely most of the time, but the risk is much higher.”
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