Bull World Health Organ 2011;89:127–136 | doi:10.2471/BLT.10.077982
e Global Safe Motherhood Initiative, launched in 1987, is
designed to improve antenatal care and counselling throughout
the world. Nutrient intake and weight gain during pregnancy are
the two main modiable factors inuencing maternal and infant
Indeed, a low body mass index (BMI) and suboptimal
weight gain during pregnancy are long-recognized risk factors for
the delivery of infants too small for gestational age.
Being born small for gestational age is a major predictor of
neonatal mortality and morbidity,
failure to grow, slow cognitive
development and chronic diseases in adulthood.
Infants too large
for gestational age also experience higher perinatal and long-term
In addition, both groups of infants are more likely
to be delivered by Caesarean section. us, reducing the delivery
of excessively small or large infants translates into fewer surgical
risks for women.
Appropriate antenatal management of maternal
nutrition, as dictated by scientic evidence, is critical in reducing
the delivery of these babies for whom both the intrauterine environ-
ment and the birth process can be life-threatening.
Maternal anthropometry diers across populations.
belonging to ethnic groups characterized by a small body size have
been reported to gain less weight on average during pregnancy
than larger women. In less-developed Asian countries, including
Viet Nam, women generally have a lower BMI and/or a smaller
gestational weight gain than in developed countries.
United States of America, for example, 2% of pregnant women
have a BMI < 18.5 and more than 50% have a BMI > 25.
a need to assess whether the current anthropometric recommenda-
tions for pregnant women of the United States National Academy
of Sciences Institute of Medicine (IOM), which are based on data
from western countries, are appropriate for preventing adverse
pregnancy outcomes across populations everywhere, including
e objectives of this study were: (i) to determine the preva-
lence of small and large size for gestational age among infants of
Vietnamese women, and (ii) to estimate the risk of giving birth
to an infant too small or too large for gestational age as a func-
tion of maternal gestational weight gain and BMI in Viet Nam.
Study setting and population
Viet Nam is a low-income country with an estimated total population
of 87 million. According to data from the United Nations Children’s
Fund, from 2003 to 2008 the average annual number of births in the
country was 1 494 000 and the average annual prevalence of low birth
weight was 7%. In 2008, the maternal mortality ratio was 150 per
Abstracts in رع, 中文, Français, Pусский and Español at the end of each article.
Objective To examine the association between gestational weight gain and maternal body mass index (BMI) among Vietnamese women
and the risk of delivering an infant too small or too large for gestational age.
Methods A prospective health-facility-based study of 2989 pregnant Vietnamese women was conducted in the city of Nha Trang
in 2007–2008. Cubic logistic regression was used to investigate the association of interest. Infants were classiﬁed into weight-for-
gestational-age categories according to weight centiles for the Asian population. Gestational age was based on the date of last menstrual
period and adjusted by the results of ﬁrst-trimester ultrasound.
Findings BMI was low (< 18.5), normal (18.5–22.9) and high (≥ 23.0) in 26.1%, 65.4% and 8.5% of the women, respectively. In
each of these BMI categories, the percentage of women who delivered infants too small for gestational age was 18.1, 10.0 and
9.4, respectively, and the mean gestational weight gain was 12.5 kg (standard deviation, SD: ± 3.6), 12.2 kg (SD: ± 3.8) and 11.5
kg (SD: ± 4.7), respectively. Among women with low BMI, the risk of delivering an infant too small for gestational age ranged from
approximately 40% if the gestational weight gain was < 5 kg to 20% if it was 5–10 kg.
Conclusion Having a low BMI, commonly found in Viet Nam, puts women at risk of delivering an infant too small for gestational age,
especially when total maternal gestational weight gain is < 10 kg.
Maternal body mass index and gestational weight gain and
their association with perinatal outcomes in Viet Nam
Dang Duc Anh,
Le Huu Tho,
Nguyen Thi Thanh Tam,
Vu Dinh Thiem,
Nguyen Thi Hien Anh,
& Hideki Yanai
Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
National Institute of Hygiene and Epidemiology, Ministry of Health, Hanoi, Viet Nam.
Khanh Hoa Health Service, Nha Trang, Viet Nam.
Khanh Hoa General Hospital, Nha Trang, Viet Nam.
School of Medicine, Tokai University, Isehara, Japan.
School of Medicine, Nagasaki University, Nagasaki, Japan.
Fukujuji Hospital, Japan Anti-Tuberculosis Association, 3-1-24 Matsuyama, Kiyose, Tokyo 204-8522, Japan.
(Submitted: 20 April 2010 – Revised version received: 16 October 2010 – Accepted: 18 October 2010 – Published online: 10 November 2010 )