The investigators aim to develop guidelines or recommendations for the management of
pregnancies after bariatric surgery based on large-scale prospective research.
The study is a multicentric prospective cohort study with UZ Leuven as the coordinating
central cite and AZ St Jan Brugge (obesity clinic and obstetric clinic), AZ St Lucas Brugge
(obstetric clinic), AZ St Nikolaas St Niklaas (obesity clinic), UZ Gent (obesity clinic and
obstetric clinic), AZ St Augustinus Wilrijk (obstetric clinic) and CHRH Mons Hainaut (obesity
clinic and obstetric clinic) as local sites.
The design for the breast milk analyses is longitudinal and will, for practical reasons, only
be initiated in UZ Leuven and UZ Gent. The investogators will collect a breast milk sample of
10 ml on day four of the postpartum and then weekly by the participants at home until the
routine 6 week postpartum consultation.
A simple, user-friendly website will be used to simplify the collection and entry of data and
to create a large database. Researchers will be able to directly and continuously register
patient data (replacing paper forms) and participants will be able to complete the
questionnaires online. The database will be available via a secure online login.
Participating researchers will only have access to their own patient database.
For breast milk analyses, the investigators wil collect a sample of 10 ml during the first
feeding moment (between 8 am and 11am) on day four of the postpartum manually or by use of a
vacuum pump. Each sample is divided into two different recipients. One part of the sample is
frozen immediately in the freezer at -20 °C. The rest of the sample will immediately be
heated to +40 °C by use of a bottle warmer. As soon as the sample is heated, it will be
ultrasonically analyzed with the MIRIS Sonicator® in order to ensure that the sample is
homogeneous. Immediately afterwards, the sample is analyzed with the Human Milk Analyzer
(HMA) (MIRIS ®, Uppsala, Sweden) for fat (g/100 ml), proteins (g/100 ml), carbohydrates
(g/100 ml), dry matter (g/100 ml) and energy (kcal/100ml). The samples that are being
collected at the participants' homes will be frozen at -20° and afterwards analyzed with the
HMA.
T0 = baseline T1 = pre-operative T2 = 3 weeks post-operative T3 = 3 months post-operative T4
= 6 months post-operative T5 = 12 of x months post-operative T6 = first trimester pregnancy
T7 = second trimester pregnancy T8 = third trimester pregnancy T9 = pregnancy T10 = 6 weeks
postpartum T11 = 6 months postpartum The number of measurements varies according to the
moment of inclusion.
Demographical data will be collected at (T0) (participant self-reporting). Age,
nationality, ethnicity, marital status, family status, educational level, employment
status and profession wil be questioned.
Anthropometric data, including body weight, waist circumference, hip circumference and
body fat percentage (if measured) are collected at all measurement points and will be
recorded by the researcher. The body length is only questioned at the first measurement.
Body height and body weight will be used to calculate the Body Mass Index (kg/m²) at
each measurement point.
During the first measurement the investigators will ask for past medical conditions
(reported by the researcher) and obstetric history (gravidity, parity, abortion -
self-report participant);
The type of procedure, date of surgery and institute of the surgeon will be recorded by
the investigators during the first measurement (Reported by researcher). Potential
problems or complications will be reported at the next measurement points. (T1-T5).
Current medical conditions (eg hypertension) will be reported at each measurement point,
together with the used medication (Reported by the researcher).
The nutritional status of the participant will be assessed by the investigators on the
basis of biochemical parameters in the venous blood. The nutritional status of the
newborn will be assessed on the basis of biochemical parameters in the venous umbilical
cord blood.
(total protein and albumin, fasten glucose level, fat soluble vitamins A, 25 -hydroxy-
vitamin D, vitamin E and vitamin K1, water soluble vitamins B1, vitamin B12 and folate
(in the serum and red blood cells (RBC), iron , (+ transferrin, transferrin saturation,
ferritin ), calcium, zinc and magnesium, hematology (hemoglobin, hematocrit and RBC
count, mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration
(MCHC), mean corpuscular volume (MCV)), coagulation (prothrombin time (PT) and activated
partial thromboplastin time (aPTT)).
During measurement time T1, T3, T4, T5, a blood sample will be taken at the department
of endocrinology and on T6, T7, T9 and T10 at the department of obstetrics-gynecology.
Investigators will ask the participants about alcohol, tobacco and sleeping habits
(self-report participant). The alcohol consumption will be asked by using the AUDIT-C
questionnaire (Alcohol Abuse Disorder Identification Test). If the participant smokes,
the amount of cigarettes or other tobacco products that are smoked daily will be
recorded.
At the beginning of pregnancy, the participant will be asked whether alcohol and tobacco
use have changed. Finally, the sleep duration will also be determined.
The food intake will be measured during three days (of which at least 1 day in the
weekend), on the basis of a 3-day food diary (self-report participant). The intake of
supplements is also questioned (self-report participant).
Physical activity will be measured by use of the Kaiser Physical Activity Survey (KPAS),
a modified version of the Baecke physical activity questionnaire, which was specifically
designed to assess the physical activity in women. The KPAS assesses different domains
of physical activity (household /family care activities, professional activities,
activities of daily life and sports/exercise). The KPAS was validated for both pregnant
and non-pregnant women.
The Moorehead-Ardelt Quality of Life Questionnaire II (MA QoLQII) will be used both
pre-and postoperatively to assess the quality of life (self-report participant). This
validated questionnaire is part of the Bariatric Analysis and Reporting Outcome System
(BAROS). The MA QoLQII has been validated in an obese population and can be used for
bariatric surgery.
The Self-Rating Questionnaire will be used to assess the psycho-social condition of the
participant. This is a Dutch-validated questionnaire to measure anxiety, based on the
American "State-Trait Anxiety Inventory" version Y of Spielberger (35). The
questionnaire included two separated self- questionnaires in which two different
concepts can be measured: state anxiety and trait anxiety. The Edinburgh Depression
Scale (EDS), a validated 10-item questionnaire, will be used to measure depression
during pregnancy and postpartum (self-report participant).
A questionnaire will be used to record the menstrual cycle (self-report participant).
The menstrual cycle's length, duration of bleeding, number of periods per year, the
pattern of the menstrual cycle and the presence of amenorrhea or oligomenorrhea will be
assessed. The questionnaire is administered at T1, T4 and T5.
Pregnancy intention is asked in non-pregnant women (self-report participant) at the
first measurement point (T0).
The use of contraceptives, which also examines the therapy adherence, is also questioned
(self-report participant). The questionnaire is administered at T1, T4 and T5.
Sexuality will be questioned to determine the relationship with fertility and the
interval between surgery and pregnancy (self-report participant). The questionnaire will
be completed at T1, T4 and T5.
Clinical pregnancy outcomes of the mother will be questioned each pregnancy trimester
(T6-T8) (Reported by the researcher) e.g. conception method, blood pressure, gestational
age, gestational diabetes, pre-eclampsia, pregnancy-induced hypertension, clinical
problems, etc. The results of the fetal ultrasounds will also be collected during each
pregnancy trimester (T6-T8). During childbirth (T9) the duration of pregnancy, labor and
delivery method will be questioned. The parameters of the newborn, including gender,
birth weight, birth length, head circumference, Apgar scores, admission to the neonatal
intensive care unit (NICU) and any complication will be recorded (T9). Finally,
postpartum data such as hemoglobin, prescribed supplements, breastfeeding, or any other
problems will be recorded.
A structured questionnaire about breastfeeding practices, developed by Guelinckx et al.
(2011), will be used at 6 months postpartum (T11) (self-report participant). This
questionnaire consists of 11 questions including the intention to breastfeed,
breastfeeding initiation, duration of (exclusive) breastfeeding and the reasons to stop
with breastfeeding.