Being pregnant

Big Mama: Plus-size pregnancy

Carrying some extra weight? Here's what you can do to have a healthy pregnancy

By Wendy Haaf
Big Mama: Plus-size pregnancy

A biological clock that’s quickly running down. A missed Pill, or a sperm that pole-vaults the diaphragm. Whatever the reason, many of us get pregnant at a less-than-perfect time, before we’ve attained financial stability, a solid relationship — or a healthy weight. And since more than one in five Canadian women of childbearing age has a weight problem, a growing number find themselves in Andrea Rowland’s shoes.

The Innisfail, Alta., mom who is expecting her second child began both her pregnancies well above her ideal weight. Andrea’s first baby had to be delivered early because he stopped growing normally, and she knows her size increases her chances of encountering complications again. “I am concerned about how my weight will affect this pregnancy,” she says.

In this situation, a woman’s worries often loom out of proportion to her real risks, according to Brette McWhorter Sember, co-author of Your Plus-Size Pregnancy: The Ultimate Guide for the Full-Figured Expectant Mom. “I think some recent studies have been reported in a skewed way in the media, which has made women more worried than they need to be.” While Sember acknowledges that larger-sized women face somewhat higher risks, she adds an important qualifier: “Most have healthy pregnancies and perfect babies.”

With that fact firmly in mind, here’s a look at what to do to keep you and your baby as healthy as possible.

Defining overweight

First, where do researchers, caregivers and doctors draw the line between optimal weight and overweight when it comes to pregnancy? “It’s based on pre-pregnancy status,” explains David Young, professor and chair of obstetrics and gynaecology at Dalhousie University in Halifax. “There are different definitions, but it’s usually related to the body mass index (BMI),” a number that takes into account both a woman’s weight and her height. Many researchers use this measurement when studying the relationship between body size and health problems. (To calculate yours, click here).

“Once your pre-pregnancy BMI falls into the overweight category, your risks start to go up,” Sember explains, “and they increase with how overweight you are.”

So which complications become more commonplace?

Well, the not-so-great news is that the odds of pretty well everything seem to climb in step with BMI — from common nuisances like back pain and urinary tract infections to more worrisome problems like postdate pregnancy and abnormalities in the baby’s growth (either too much or not enough).

“The risk of most things increases at a rate of about 11/2 to three times normal,” Young explains. “But that has to be considered in context.”

That means scary but uncommon problems, such as certain congenital abnormalities, remain relatively rare — increasing by two to three chances in 1,000. More widespread conditions, such as pregnancy-induced hypertension and gestational diabetes, also increase proportionally. Young cites the example of pre-eclampsia, which crops up in five to 10 percent of women with an optimal BMI. “It’s not like suddenly it’s a 95 percent chance [if],” he stresses.

Due in part to the increased prevalence of such conditions in bigger moms, the probability of interventions during birth, including induction and Caesarean, also rise.

While you can’t wave a wand and make these risks magically disappear, “you certainly can moderate them,” reassures Philip Hall, professor of obstetrics, gynaecology and reproductive sciences at the University of Manitoba and director of fetal assessment at St. Boniface General Hospital in Winnipeg.

The first step? Find a knowledgeable, compassionate caregiver. You’ll undoubtedly feel most comfortable with a physician or midwife who’s vigilant yet relaxed, and offers encouragement and guidance in lieu of lectures on the perils of excessive weight gain.

A caregiver with experience looking after larger moms should be well-versed in size-specific issues, such as the importance of using the correct blood pressure cuff (one that’s too small can artificially inflate the reading); special wound-closing techniques that cut the risk of post-C-section infection in large women; and any other special care or extra tests you may need.
For example, if you weren’t screened for pre-existing Type 2 diabetes before conceiving, it may be prudent to undergo blood sugar testing early in the second trimester, rather than waiting until 24 to 28 weeks, when the test for gestational diabetes is typically performed. Some experts also advise plus-size moms to take a heftier-than-usual dose of folic acid (one milligram versus the typical 0.4), both before and after conception, to protect against neural tube defects.

An experienced midwife or doctor may also refer you for at least one or two ultrasounds later in pregnancy to keep tabs on how well the baby is growing. That’s because the usual method of monitoring the baby’s progress — measuring the height of the uterus — tends to be less accurate in full-figured moms.

Your caregiver can also give you personalized guidance about optimal weight gain (which is a matter of debate) and refer you to other professionals when it’s appropriate (say, a physiotherapist who specializes in maternity care if you’re experiencing a lot of back pain) instead of brushing off such complaints as a consequence of your size.

A knowledgeable childbirth educator or doula can also answer questions about labour and birth, and help you develop strategies to maximize your chances of ending up with the kind of birth you want. “I took Lamaze classes and met with our doula several times before the birth, and that gave me incredible peace of mind,” says Barb Anderson,* who lives in Kamloops, BC.

During labour, an experienced doula can provide tips for coping with contractions, and literally offer support — helping to hold you in a squatting position, or assisting with position changes. And some studies suggest the presence of a doula reduces the likelihood of interventions and may even shorten labours (though this research didn’t specifically look at larger moms). That may be particularly valuable for plus-size women, since at least one trial found plus-size moms labour longer on average than their skinnier sisters — which Sember believes may lead doctors to intervene unnecessarily. “I do believe longer labours are a cause of C-sections,” she says.

Food for thought

How should you be eating? “Dieting is really discouraged,” stresses Joel Ray, a clinician-researcher in medicine, obstetrics and gynaecology at St. Michael’s Hospital in Toronto. “It’s not so much how much you’re eating as the quality and type of food,” adds Kris Robinson, a clinical midwifery specialist for the Winnipeg Regional Health Authority. Basically, most experts suggest expectant moms — plus-size or not — consume a diet in keeping with Canada’s Food Guide: rich in veggies, whole grains and lean protein like chicken, soy and fish, and low in unhealthy fats and simple starches.

It really comes down to removing some of the simple sugars, such as fruit juice, white bread and white rice, says Ray, and substituting more slowly digested alternatives like whole wheat bread and brown rice. This keeps a lid on blood sugar levels, which in turn helps prevent the baby from growing too large (which can lead to difficulties during delivery). Spreading the day’s food intake over six smaller meals and snacks instead of three bigger meals also keeps your blood sugar on an even keel.

When you arrange your plate, have half the plate veggies, one quarter protein, and one quarter carbohydrates such as rice, potato or noodles. Treat yourself to a new cookbook, and experiment with healthy foods you haven’t tried before. Prepare big batches of cut, washed veggies when you’re feeling up to it — maybe while you’re preparing dinner anyway — and stash them in the fridge to encourage healthy snacking.

For more individualized advice, there’s nothing like working with a registered dietitian, says Liz Wilson* of Barrie, Ont. “I would highly recommend it to anyone. She looked at my weekly food journal and gave suggestions on how to cut back without risking poor nutrition or making me feel deprived.”

*Names changed by request.

Most of us know the importance of exercise in curbing excessive weight gain, maintaining healthy blood pressure levels, helping your body use insulin (which controls blood sugar) more efficiently, and building your stamina for labour and delivery. But we could all use workable advice on how to incorporate regular physical activity into our lives — no Lycra tights or gym membership necessary.

That’s where Michelle Mottola comes in. The director of the R. Samuel McLaughlin Foundation Exercise and Pregnancy Laboratory at the University of Western Ontario in London, Mottola is studying the effect of a simple walking program (plus nutritional counselling) on women who are at high risk of developing gestational diabetes due to weight, family history or ethnic background. Women who enrol in the trial walk at a comfortable pace three to four times per week. (What’s “comfortable”? You should be able to carry on a conversation.) They start off at 25 minutes per session, adding two minutes per week until they reach 40 minutes, the level they maintain until giving birth, and beyond.

According to preliminary data: “We’ve been finding our program works really well — by two months postpartum, most women are at or below their pre-pregnancy weight,” Mottola says. “We haven’t seen any gestational diabetes, nor have we seen high blood pressure.”

So how do you motivate yourself to move a little more? An inexpensive pedometer is a terrific tool to gauge your current activity level, and inspire you to reach the recommended 10,000 steps per day.

Even without a pedometer, Kanata, Ont., mom Anna McCready incorporated walking into her day by hoofing it back and forth to school, taking strolls at work, and choosing the stairs over the elevator. “It helped with my weight, my mood and my flexibility, and just helped me feel good about myself,” she says.

Of course, if you’re so inclined, you don’t have to limit yourself to pounding the pavement. “I’d never done yoga before, but I took a prenatal yoga class and really enjoyed it,” recalls Anita MacDonald of Orleans, Ont. “I also did a lot of swimming.”
Maintaining and sustaining

Many plus-size moms find pregnancy is the perfect time to make the small, sustainable changes that add up to better health. “I was more motivated during my pregnancy than I ever have been to take better care of myself, for my baby’s sake,” Barb Anderson observes.

In the shorter run, taking good care of yourself will optimize your baby’s health and could even help disprove predictions that you won’t be able to have the birth you’re hoping for. “For my second birth, my obstetrician didn’t think I would be able to have a VBAC (vaginal birth after Caesarean),” says Laura Landry, of Saint- Jean-sur-Richelieu, Que. “He was very surprised!”

Judging by the number of news stories on rising obesity rates, you’d think women who start pregnancy at a lighter-than-ideal weight are just a tad more common than unicorns. But stats say 19.5 percent of Canadian women aged 20 to 34 are underweight — which means a substantial minority of moms-to-be are too. So what are the health considerations unique to underweight pregnancy?

First, the good news. According to a 2001 study, underweight women actually run a slightly lower risk of certain complications — including pre-eclampsia, gestational diabetes and postpartum hemorrhage — than moms-to-be in the “appropriate” weight range. They are also less likely to have labour induced, a forceps delivery or a C-section.

On the other hand, low pre-pregnancy weight is linked with a higher-than-average risk of premature birth, and of having a baby that’s smaller than expected, based on age — which may in turn increase the risk (though it’s a small likelihood) of needing extra TLC in the neonatal intensive care unit.

So, if you were underweight before conceiving, what can you do to have the healthiest possible pregnancy, and to optimize your baby’s growth?

While some women are skinny by nature, others may be underweight due to a health problem. “Eating disorders are fairly common in young women,” notes Kathi Wilson, city-wide chief of midwifery at St. Joseph’s Health Care London (Ont.) and London Health Sciences Centre. Smoking and substance abuse can also curb appetite. If you’re struggling with any of these issues, confide in your caregiver, who can refer you to someone who can help.

Pay attention to nutrition
While being underweight prior to conception has been linked to premature birth and low birth weight, some studies suggest that part of that risk is actually related to gaining too little weight during pregnancy. It appears that heading into pregnancy with low stores of certain vitamins and minerals, and inadequate nutritional intake while pregnant, both play their part.

If you don’t take in enough calories to build up the 25 to 30 pounds needed for the baby, placenta, extra blood supply, etc., you’ll end up with a net weight loss, says Jan Christilaw, an obstetrician/gynaecologist and VP of medicine at BC Women’s Hospital in Vancouver. That may affect your underlying health, for example, sabotaging the strength of bones and muscles. “And if you’re not getting enough nutrition during pregnancy, your baby will not grow properly,” she says.

So how do you get the nutrients you need?

• Take a prenatal vitamin that contains folic acid, as recommended by your caregiver.

• If you’re severely underweight, your caregiver may refer you to a dietitian who can offer guidance about how to fill any nutritional gaps.

• You do need extra calories, but it’s best to get them from foods that are packed with nutrients, instead of ones that are full of empty calories. “That means vegetables, fruits, whole grains and protein, and limit treats,” says Christilaw. Nuts, seeds, dried fruits and avocados are all examples of higher-calorie foods that are also rich in vitamins and minerals.

If, despite your best efforts, the numbers on the scale still climb a little more slowly than recommended, take heart. “Most women who are metabolically underweight and don’t gain much during pregnancy grow perfectly healthy, good-sized babies,” Wilson reassures. “I had a client who only gained 15 pounds in each of her pregnancies — and she had eight-pound babies.”

Body Mass Index (BMI) is a tool for estimating weight status in proportion to height. It can be calculated in the following ways:

Weight in pounds x 703
(Height in inches)²


Weight in kilograms x 10,000
(Height in centimetres)²

Lousy at math? Many websites feature automatic BMI calculators. You can find one at:

For example, a five foot, four inch woman with a pre-pregnancy weight of 160 pounds has a BMI of 27.5; a woman of the same height who weighs 180 pounds has a BMI of 30.9.

According to the World Health Organization, a pre-pregnancy BMI under 20 is low; 20 to 27 is considered healthy; and more than 27 is deemed overweight. BMI isn’t perfect (for example, because muscle is more dense than fat, BMI doesn’t accurately reflect risk for, say, a marathon runner), but it’s a useful method of estimating the likelihood of certain health problems.

Resources Click on Find a Dietitian to locate one in your area. for tips, resources and encouragement from Brette McWhorter Sember.

Your Plus-Size Pregnancy: The Ultimate Guide for the Full-Figured Expectant Mom by Brette McWhorter Sember with Bruce D. Rodgers, Barricade Books 2005.

Carrying a Little Extra: A Guide to Healthy Pregnancy for the Plus-Size Woman by Paula Bernstein, Marlene Clark and Netty Levine, Berkley Books 2003.

Nutrition and Exercise Lifestyle Intervention Program (NELIP) If you live near London, Ont., and you’re pregnant, less than 20 weeks gestation, overweight, currently not exercising and at risk for gestational diabetes, and you’d like to find out more about participating in the above study, call: (519) 661-2111 ext. 88366.

This article was originally published on Jul 20, 2007

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