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Obesity Surgery,
11
, 59-65
© FD-Communications Inc. Obesity Surgery, 11, 2001 59
Background: Severely obese women have higher
obstetric risks and poorer neonatal outcomes.
Weight loss reduces obstetric risk. The introduction
of a laparoscopically-placed adjustable gastric band,
a safe and effective method of weight loss, has given
us the ability and responsibility to adjust the band in
relation to pregnancy.
Objective: Our aim was to devise a safe manage-
ment plan to achieve healthy maternal weight gain
(Institute of Medicine 1990) during pregnancy.
Methods: In a cohort group of 650 patients to have
a Lap-Band
®
placement for severe obesity, we have
reviewed the management of the band and preg-
nancy outcomes of all women (n=20) to complete a
pregnancy (n=22) with a band in-situ.
Results: All 22 pregnancies were singleton, with
no primary caesarean sections (3 for recurring indi-
cations). The mean maternal weight gain was 8.3 kg
compared with 15.2 kg for the 15 previous pregnan-
cies of women in this group (p<0.05). There was no
difference in birth weights. Obstetric complications
were minimal, and there were no premature or low
birth weight infants. 11 of 15 subjects with active
management of the band achieved a maternal weight
gain within the advised range compared with only 2
of 7 prior to this.
Conclusion: The ability to adjust gastric restriction
allows optimal control of maternal weight change in
pregnancy and should help avoid the risks of exces-
sive weight change.
Key words: Morbid obesity, gastric banding, laparoscopy,
pregnancy, obstetric management
Introduction
Pregnancy in severely obese women is associated
with increased risks and costs. These women suffer
an increased incidence of complications during
pregnancy including hypertension, preeclampsia,
late fetal death and gestational diabetes.
1-5
There is
a higher risk of induction of labor, primary caesar-
ian section and perioperative morbidity.
6-8
Their
infants are more likely to have fetal growth abnor-
malities, macrosomia and intrauterine growth
retardation, and are more likely to require admis-
sion to a neonatal intensive care unit.
2
They may
also be at greater risk of developmental abnormal-
ities including neural tube defects.
9-11
Duration of
hospital stay and overall cost is strongly related to
maternal weight.
8
Weight loss has been shown to lead to improved
fertility and lower obstetric complications.
5,12
Effective and durable weight loss is rarely achieved
by medical programs alone, and in the reports
cited, the weight loss was achieved by gastric sta-
pling or bypass surgery. These forms of bariatric
surgery generate a fixed restriction to food and/or
malabsorption, which continues through the preg-
nancy and thus must be seen to carry risks as well
as benefits. Specific nutritional deficiencies may
cause fetal abnormalities,
13
and weight-loss or
inadequate weight gain during pregnancy may lead
to low birth weight with its associated risks.
14-17
The introduction of a laparoscopically-placed
adjustable gastric band for the surgical manage-
ment of morbid obesity provides an opportunity for
achieving weight loss prior to the pregnancy and
Pregnancy after Lap-Band
®
Surgery: Management
of the Band to Achieve Healthy Weight Outcomes
John B. Dixon, MBBS, Dip RACOG, FRACGP; Maureen E. Dixon, BSc,
Dip Ed; Paul E. O’Brien, MD, FRACS
Monash University Department of Surgery, Alfred Hospital, Melbourne, Victoria, Australia
Reprint requests to: Dr. John Dixon, Monash University
Department of Surgery, Alfred Hospital, Melbourne 3181,
Australia. Tel: 61 3 9903 0608; fax: 61 3 9510 3365; e-mail:
john.dixon@med.monash.edu.au
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60 Obesity Surgery, 11, 2001
Dixon et al
then modifying the degree of restriction of food
intake during the pregnancy to ensure optimal out-
come for the mother and the baby. The gastric band
is placed 2 cm below the gastroesophageal junction
and functions by producing gastric restriction and a
sense of early satiety. There is no malabsorption.
The band has an internal balloon into which saline
can be instilled or removed to adjust the degree of
gastric restriction. The balloon is connected via
tubing to a Portacath reservoir attached to the ante-
rior rectus sheath and adjusted percutaneously.
Further description and outcomes have been pub-
lished elsewhere.
18
Optimal weight gain for pregnancy requires a
balance between allowing sufficient weight gain to
allow for normal fetal growth and development,
and yet avoiding excess weight gain with its obstet-
ric risks, macrosomia and post-pregnancy weight
retention. The Institute of Medicine (IOM) in 1990,
issued total gestational weight gain recommenda-
tions based on pre-pregnancy BMI.
19
These guide-
lines may not apply to severely obese women
where recommendations for a minimum weight
gain may be unnecessary.
20,21
We have found no
reference recommending a net weight loss during
pregnancy.
From a group of 650 patients who have had
placement of the Lap-Band system
®
(BioEnterics
Corporation, Carpinteria, CA), a laparoscopically-
placed silicone adjustable gastric band, we have
followed all women having a pregnancy. We pre-
sent the results of these pregnancies and our cur-
rent approach to the management of the Lap-
Band
®
system during pregnancy. In addition,
obstetric histories have been taken from severely
obese women presenting for Lap-Band
®
surgery,
and their incidence of obstetric complications is
compared with the group who have completed
pregnancy after Lap-Band
®
placement.
Methods
Patients with a body mass index (BMI) greater than
35 kg/m
2
, suffering significant medical, physical or
psychosocial disabilities and who have attempted
weight reduction by other means for at least 5 years
were considered for entry into the Lap-Band
®
pro-
gram. Preoperative assessment included as part of
the medical assessment a questionnaire that
enquired about infertility, parity and obstetric his-
tory. Details of this history were then obtained at
preoperative interview or at post-operative review
visits. The history was dependent on the mother’s
recall of obstetric events. A history of gestational
hypertension was difficult in many cases to further
classify; consequently this category contains all
women diagnosed with hypertension in pregnancy
who had no pre-gestational hypertension.
All patients were followed regularly at a central
multidisciplinary bariatric clinic and urged to
inform us of any intention to become pregnant or
of pregnancy, as soon as possible. Patients are
advised to delay pregnancy for at least 1 year after
Lap-Band
®
placement, but this recommendation is
not always followed, as obesity-related infertility
often resolves with early weight loss.
During the period of study an active approach for
the management of the Lap-Band
®
during preg-
nancy evolved. The key elements of this were:
1) Close co-operation was established with the
obstetrician.
2) As early as possible during pregnancy, all fluid
was removed from the band to minimize band
restriction, thereby allowing optimal nutrition dur-
ing embryogenesis and minimizing the effect of the
band on hyperemesis during the first trimester.
3) Optimal weight gain for the pregnancy was dis-
cussed with all women, and fluid was added after
14 weeks gestation or later if weight gain is exces-
sive. The adjustment was aimed to limit excessive
weight gain rather than to assist with weight loss.
4) All fluid was again removed from the band at 36
weeks gestation to minimize its impact on delivery
and the establishment of lactation. Once lactation
was established, the band was adjusted to near pre-
pregnancy level, to allow for continued weight-loss
or weight maintenance as appropriate. Feeling the
band reservoir through the skin allows us to make
band adjustments, and we have not required ultra-
sound to locate the site in any pregnant women to
date.
5) Optimal weight gain for pregnancy was based
on the IOM recommendations for weight gain at
varying BMI levels. In addition, we did not set a
minimum weight gain for those with a BMI >35
kg/m
2
at the commencement of pregnancy.
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Obesity Surgery, 11, 2001 61
Obesity and Pregnancy: Outcomes after Lap-Band® Surgery
Data Analysis
Descriptive statistics include mean and standard
deviation for continuous variables. The chi-squared
test was used for binary variables to assess the sig-
nificance of proportions. Unpaired t-test was used
to assess pregnancy weight outcomes before and
after weight loss. A p-value of 0.05 or less was con-
sidered statistically significant.
Results
We obtained obstetric histories from 264 parous
women prior to Lap-Band
®
surgery; 88 (30%) of
the 264 parous women had had at least one cae-
sarean section, with 168 (31%) of 621 babies born
by caesarean section. This is significantly above
the Australian caesarean section rate of 20%
(p<0.01).
22
Gestational hypertension complicated
pregnancies in 98 women (37%). It was a factor in
35% of 264 primigravids, 34% of 217 second, 39%
of 101 third and 38% of 39 fourth or subsequent
pregnancies, all significantly higher than the
expected community incidence of 10-13%
(p<0.001).
23
Gestational diabetes had been diag-
nosed in 9.4% of women compared with a commu-
nity incidence of 5.5% (p<0.05)
24
with universal
screening.
Twenty women have completed 22 pregnancies
with a Lap-Band
®
in-situ. One woman (not
included in this study) had a spontaneous first
trimester abortion. The details of the mothers’
demographics, weight gain and pregnancy out-
comes are shown in Table 1. All were singleton
pregnancies. Nineteen of 22 had vaginal deliveries,
with two primigravids requiring low forceps assis-
tance. Three had elective caesarean section for
recurring indications: two for previous obstructed
labors and one for previous pelvic fracture. There
were no primary caesarean sections.
Eight of these 20 women suffered infertility prior
to weight loss. Four had primary and four had sec-
ondary infertility. In seven, infertility appeared to
be related to anovulation associated with severe
obesity and resolved spontaneously with weight
loss. The remaining woman achieved a pregnancy
following in vitro-fertilization.
Ten women had a past history of 15 previous
deliveries, with average maternal weight gain for
pregnancy of 15.3 (SD 8) kg and a mean infant
birth weight of 3,415 (SD 520) gm. The mean
maternal weight gain in the patients with a band in-
situ was significantly less 8.3 (SD 7) kg (p<0.05),
but this was not at a cost of lower birth-weight
(mean 3,495 SD 485 gm).
There were few pregnancy complications. One
primigravid woman developed mild uncomplicated
gestational hypertension in late pregnancy. A dia-
betic woman developed mild hyperglycemia late in
her second pregnancy. She had previously devel-
oped gestational diabetes in her first pregnancy,
and 2 years later type 2 diabetes was diagnosed and
controlled with diet. Before Lap-Band
®
placement,
fasting blood glucose was 9.6 mmol/l and HbA1c
7.8%. With weight loss after surgery and prior to
pregnancy she was normoglycemic with fasting
glucose 4.5 mmol/l and HbA1c 5.4%. Fluid was
added to the band during pregnancy to limit weight
gain. She re-developed mild diabetes late in preg-
nancy. Her macrosomic infant (4,540 gm) was
delivered normally and required management of
hypoglycemia in the early neonatal period. There
were no long-term effects.
In this small group of 22 pregnancies, there was
a lower incidence of gestational hypertension
(p<0.05) and primary caesarean (p<0.05) than the
severely obese comparison group.
There were only two other maternal complica-
tions, both possibly indirectly related to weight
Table 1. Pregnancy (N=22) details for 20 women with Lap-
Band in situ during pregnancy
Mean (SD) Range
Maternal age (years) 28.8 (4.4) 22-40
Parity 1.85 (0.8) 1-4
Pre Lap-Band‚ weight (kg) 129 (18) 105-172
Pre Lap-Band‚ BMI (kg/m
2
) 46.4 (6.0) 37-60
Time from L/B placement to
conception (months) 16.6 (11) 1-43
% EWL at start of pregnancy (%) 45 (17) 17-80
Pre-pregnancy BMI (kg/m
2
) 35 (7) 26-49
Pre-pregnancy weight (kg) 99 (19) 72-145
Pre-delivery weight (kg) 107.3 (17) 82-139
Pregnancy weight gain (kg) 8.3 (7) -8-26
Gestation (weeks) 39.3 (1.3) 37-42
Birth weight (gm) 3495 (485) 2735-4540
Infants Male : Female 14:8
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62 Obesity Surgery, 11, 2001
Dixon et al
loss surgery. One woman managed at a distant cen-
ter without liaison developed hyperemesis in late
pregnancy, having a net weight loss of 2 kg for the
pregnancy. The band had not been adjusted for the
pregnancy and she had not attended for follow-up.
She was induced for hyperemesis but continued to
vomit post-natally and required urgent post-natal
removal of all fluid to control vomiting. Another
woman developed symptomatic gallstones with
frequent attacks of biliary colic and an episode of
pancreatitis during the last trimester. Fluid was
removed from the band on diagnosis of the biliary
colic but despite this she had a net weight loss of 7
kg for the pregnancy. She had an uncomplicated
delivery of a 3,560 gm healthy male after induction
at 38 weeks gestation. An uneventful laparoscopic
cholecystectomy was performed 6 weeks post-par-
tum.
There were no premature deliveries, low birth
weight infants (< 2,500 gm), congenital abnormal-
ities or major neonatal problems. There were 5
infants with weight less than 3,000 gm and 4 over
4,000 gm with one macrosomic infant (> 4,500
gm).
Maternal weight gains for pregnancy with pre-
pregnancy BMI levels are plotted in Figure 1, with
IOM recommended gains indicated and a possible
adjustment for maternal BMI>35 kg/m
2
also indi-
cated (Table 2). Two of three who had all fluid
removed for the pregnancy and were not reviewed
until after the pregnancy had excessive weight
gain. Three of four who had fluid in the band and
had no adjustments at all during pregnancy had a
net weight loss. Of 15 with planned active man-
agement, all had the fluid removed from the band
early in pregnancy and were given advice regard-
ing nutrition and optimal weight gain. Only 6
required the addition of fluid during pregnancy.
Eleven of 15 patients with active band management
had weight gain within the advised range. Only
two of seven treated prior to establishing the active
management plan achieved weight gain within this
range.
Discussion
The obstetric histories of severely obese women
presenting for Lap-Band
®
gastric restrictive
surgery are consistent with known increased risks
of hypertension during pregnancy, gestational dia-
Figure 1. Weight gain for pregnancy vs pre-pregnancy BMI (N=22).
Institute of Medicine recommendations for gestational weight gain.
Possible adjustment for no recommended minimum gain during pregnancy
for women with a BMI >35 kg/m
2
.
1,36,37
Fluid removed to relieve Lap-Band restriction.
Lap-Band restriction not altered for pregnancy.
Active management of band.
30
25
20
15
10
5
0
-5
-10
15 20 25 30 35 40 45 50 55
Maternal weight gain (kg)
Start pregnancy BMI (kg/m
2
)
n
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Obesity Surgery, 11, 2001 63
Obesity and Pregnancy: Outcomes after Lap-Band® Surgery
betes and high caesarean section rate in these
women. In our series of 22 pregnancies, these
obstetric complications were lower than the com-
parison group and consistent with reports from
other groups reporting pregnancy outcomes after
bariatric surgery and for a non-obese popula-
tion.
5,12,23,24
Neonatal outcomes were also excel-
lent, with a mean birth weight of 3,495 gm consis-
tent with community birth weight, and not different
from the mean birth weight of infants born to these
women prior to weight loss surgery.
25
A low mean
birth weight has been reported following other
non-adjustable forms of weight loss surgery.
14,15,26
Obese women are extremely concerned at the
possibility of gaining excessive weight during
pregnancy and there is some justification for this
concern. Obese women tend to gain less weight
during pregnancy than women of normal weight
do.
27
However, they have greater weight retention
after pregnancy and tend to gain more weight
between pregnancies.
28
For this reason, women are
reluctant to have their gastric restriction relieved
for pregnancy. A policy of removing the fluid may
lead to excessive weight gain. Because of this fear,
women may delay informing us of the pregnancy
in an attempt to continue weight loss. However, not
relieving the gastric restriction may put the fetus at
risk of nutritional deficit and low birth weight, both
preventable risks, which may have long-term con-
sequences. Fetal malnutrition in infants born into
an affluent society may have increased risk of the
metabolic syndrome as proposed by Barker.
17,29
These children have, of course, a family history of
severe obesity. Active management of the
adjustable band permitted women to choose a
healthy weight gain for their child with the knowl-
edge that, if necessary, restriction could be added
during the pregnancy to prevent excessive weight
gain. Only six of our patients required some added
restriction during pregnancy. With the presence of
adjustability, they are also reassured that increase
of the level of gastric restriction when lactation is
established will minimize weight retention and
allow continued weight loss.
Nutritional considerations are also important
during pregnancy. It is vital that women of child-
bearing age have adequate folic acid prior to preg-
nancy to minimize the risk of neural tube defects.
An oral supplement of 400 mcg /day is recom-
mended for all women who could become preg-
nant.
30
We have recently found that patients losing
weight after Lap-Band
®
surgery require higher
plasma levels of folate and vitamin B12 to main-
tain normal homocysteine levels.
31
Multivitamin
supplements containing folate, vitamin B6 and vit-
amin B12 help minimize this effect. Recent weight
loss by the mother may put the child at increased
risk of neural tube defects. Robert et al
32
found an
association between weight loss in the month after
conception and neural tube defect. While selective
multivitamin supplements during pregnancy may
be appropriate, care should be taken to avoid risk.
Supplement of vitamin A more than 5000 IU/day
should be avoided.
33
Iron deficiency is not associated with gastric
restrictive Lap-Band
®
surgery, and routine supple-
mentation during pregnancy is of no proven value
and unnecessary.
34
Iron tablets can be locally ero-
sive
35
in association with delayed gastric emptying,
a necessary feature of gastric restrictive surgery.
Monitoring hemoglobin and iron status prior to and
during pregnancy would be more appropriate, with
liquid oral or parenteral iron therapy given if nec-
essary. A calcium intake of 1200-1500 mg is rec-
ommended throughout pregnancy and lactation,
and dietary advice to achieve this intake is neces-
sary.
36
Severely obese women are at high risk for obstet-
ric complications. The introduction of a laparo-
scopically-placed, adjustable and effective method
of weight loss gives us the opportunity to use this
system in severely obese women planning future
pregnancies, to reduce obstetric risks in addition to
the other advantages of losing weight. While it is
Table 2. Recommended weight gain in pregnancy
BMI Range Lower Upper
wt gain kg (lbs) wt gain kg (lbs)
BMI < 20* 11.5 (25) 18 (39)
BMI 19-26* 11.5 (25) 15.5 (34)
BMI 26-29* 7 (15) 13 (24)
BMI 29+* 7 (15) 13 (24)
BMI 35+** 0 13 (24)
*Institute of Medicine 1990 recommendations for weight gain in preg-
nancy.
** Minimum weight gain in pregnancy for severely obese women in preg-
nancy may be inappropriate.
1,37,38
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64 Obesity Surgery, 11, 2001
Dixon et al
ideal for women to lose most of their excess weight
prior to pregnancy, it is reassuring that the system
can be used with the knowledge that band restric-
tion can be decreased during pregnancy.
Conclusion
In our experience, an active management which
utilizes the adjustability of the Lap-Band
®
and
planned and careful monitoring of pregnant women
with a Lap-Band
®
in situ, has achieved optimal
weight control and appears to be associated with
reduction of the risks and complications of preg-
nancy for the mother and infant.
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(Received September 26, 2000; accepted October 25, 2000)
