Pregnant pause

Health is not valued until sickness comes.

Dr Thomas Fuller (1654–1734)

This month Canadian Family Physician focuses on pregnancy and maternal health. The powerful cover story, written by Dr Sarah de Leeuw, profiles the important work of the joint task force on rural surgical and obstetric care, shown through the lens of the community of Bella Bella in remote British Columbia.¹ But maternity care has many challenges.

In the past 3½ decades, Canada has seen a marked increase in obesity. The proportion of overweight and obese women in Canada rose from 34% in the late 1970s to about 55% in 2004.² Almost half of Canadian women of childbearing age are overweight or obese.³ Such excess weight is associated with increased rates of gestational diabetes mellitus, type 2 diabetes, preeclampsia, eclampsia, thromboembolic disease, and congenital anomalies.⁴ Further, delivery complications such as shoulder dystocia and cesarean section are increased in this population.⁴

Recognizing the risks associated with prepregnancy excess weight, the Society of Obstetricians and Gynaecologists of Canada has recommended⁵ that women should ideally begin pregnancy with a body mass index (BMI) less than 25 kg/m². Recommendations for gestational weight gain in singleton pregnancies have also been made by the Institute of Medicine (IOM) and adopted by Health Canada. These depend on a mother’s prepregnancy BMI: for those who are underweight, appropriate gestational weight gain is 12.5 to 18.0 kg; for those of normal weight, 11.5 to 16.0 kg; for those who are overweight, 7.0 to 11.5 kg; and for those who are obese, 5.0 to 9.0 kg.^6,7

In this issue, companion research studies by Woolcott and Piccinini-Vallis and their colleagues add to our knowledge of weight gain during pregnancy and its implications for the future health of both women and their children.^8,9

The first article (page e400) is a descriptive, epidemiologic study using the Nova Scotia Atlee Perinatal Database⁸ to assess prepregnancy BMI and gestational weight gain in more than 54 000 singleton pregnancies. The authors were also able to assess interpregnancy weight change in almost 23 000 pregnancies. They found that half of the women in the study were overweight or obese before pregnancy, and excess weight gain was observed in almost 58% of women, with half of these women above the IOM recommended weight gain by at least 4.8 kg. A third of women entered a subsequent pregnancy weighing at least 4.8 kg more than they had weighed at the start of their previous pregnancy.

The second study (page e407) examined the trajectory of weight gain in a sample of 280 women in Halifax, NS,⁹ to answer 2 key questions: Does prepregnancy BMI influence the trajectory of gestational weight gain among women with singleton pregnancies receiving prenatal care in primary care? and What is the discordance between actual and targeted weight gain by gestational age, based on the 2009 IOM guidelines, among women with singleton pregnancies receiving prenatal care in primary care? The authors found that women who were overweight gained the most excess weight during their pregnancies.

The results of both studies are congruent with national trends and once again raise the alarm that excess weight gain during pregnancy and the attendant health complications provide us with crucial glimpses into a woman’s future cardiovascular health risks and those of her children.^4,10 What is the optimal way to respond to such worrying trends in gestational weight gain? As the authors themselves state, “Successful strategies are needed to promote healthier body weight in reproductive-aged women, optimize gestational weight gain, and support postpartum weight management.”⁸

The traditional approach to tackling problems like excess weight is a medical one, focusing on individual counseling by family physicians or other primary care providers. The results of a study by Klein and colleagues at the University of Alberta in Edmonton (page e393) should give us pause at such conventional solutions. They found “that lifestyle habits among physician faculty do not routinely meet recommended guidelines, and that physicians might counsel patients less frequently on lifestyle guidelines that they themselves are not meeting.”¹¹

On the problem of excess weight gain in pregnancy and the implications for the future health of both women and their families, new thinking is needed.

• Copyright© the College of Family Physicians of Canada