VANCOUVER, B.C. – When it comes to counseling women about weight gain during pregnancy, there is plenty of room for improvement, new data suggest.

In a survey of more than 300 pregnant women, less than a third reported being counseled on the topic, researchers reported at the annual meeting of the Society of Obstetricians and Gynaecologists of Canada. And even fewer, merely an eighth, were counseled correctly about how much weight to gain.

In likely related findings, three-fourths of women who were overweight or obese before conceiving planned to gain more weight than was recommended for them in guidelines.

"A lack of reported counseling has been associated in the literature with inappropriate weight gain, both excessive and inadequate," said lead investigator Dr. Sarah McDonald, an obstetrician-gynecologist at McMaster University in Hamilton, Ont. "So these findings were very concerning for us."

She noted that most women who were approached agreed to participate in the survey and were comfortable when it came to discussing weight. Therefore, "it appeared unlikely that the lack of reported counseling was due to patient-driven factors, apart from possibly forgetting."

Interestingly, a staggered companion survey of the providers had dramatically different findings, showing high reported rates of counseling. "It was like I was surveying people on a different planet," she commented. "We think we are doing very well," yet there is an obvious discrepancy that is as yet unexplained.

Citing the obesity epidemic, Dr. McDonald endorsed repeated counseling of women about weight, both before and during pregnancy.

"Obviously, an optimal BMI [body mass index] prepregnancy is ideal, but that’s not the situation where most of us come into contact with our patients – it’s when they are already pregnant. Then, I think talking about optimal gestational weight gain to not compound the problems of overweight and obesity is important," she said. "But given the size of the [obesity] epidemic, [the approach has] got to be multipronged."

In 2009, the U.S. Institute of Medicine released new recommendations regarding gestational weight gain, tailored to prepregnancy BMI, that have been adopted by Canada and other countries.

"However, previous studies done in the era of the 1990 guidelines have shown that only about 30% to 40% of pregnant women gained the appropriate amount of weight during pregnancy," Dr. McDonald noted. "And we were curious what was going on in the era of the new guidelines."

The investigators surveyed 310 women (94% of those approached) who made at least one visit to representative Hamilton prenatal clinics, other than for pregnancy diagnosis, and currently had a live, singleton gestation. The women’s mean age was 30 years, and the median gestational age was 33.0 weeks. Fully 74% were white, and for 43%, the birth would be their first. They had a mean prepregnancy BMI of 25.1 kg/m².

"Interestingly enough, 84% of the women reported that they were either comfortable or very comfortable talking about weight-related issues with their care provider, despite the fact that the mean BMI [in this study] is already in the overweight category prepregnancy," Dr. McDonald observed.

Only 29% of the women reported that their provider counseled them to gain a specific amount or range of weight, and for just 12% overall, that amount or range was correct according to the new guidelines. Additionally, only about a quarter of women reported being told that there were risks associated with gaining too much weight or too little weight during pregnancy.

The median number of prenatal visits before the survey was 10 for the study population, she pointed out, and "so there were multiple opportunities for discussion about weight gain."

"We wondered, are clinicians just too busy to be talking about weight and weight-related matters, and nutrition, and preventive-type medicine?" said Dr. McDonald. Yet, nearly all of the women (97%) reported being counseled to take a vitamin.

When asked how much weight they planned to gain during pregnancy, only 12%-54% of women, depending on prepregnancy BMI category, cited an amount within the guideline-recommended range for them. In particular, in a finding that she described as "alarming," 75% of overweight and obese women were planning to gain more weight than was recommended for them.

The proportion of women counseled about weight gain differed by the type of provider that had provided the majority of a woman’s pregnancy care; it was 40% for midwives, 24% for obstetricians, 23% for general practitioners, and 28% for other providers. The proportion that was correctly counseled showed a similar pattern, but the differences were not significant.

The investigators are still analyzing data on whether women had been counseled about weight in a previous pregnancy, which might have led providers to assume they already had the information, according to Dr. McDonald. But "that is a dangerous assumption, it would appear, based on our results."

Dr. McDonald reported that she had no relevant financial disclosures.

Women Are Seldom Counseled About Weight Gain During Pregnancy