Material and methods: The study is a case control study of women registered at El-Shatby Maternity University Hospital at the time of delivery in the period between June 2009 and June 2010. The cases were 50 pregnant obese women (BMI> 30Kg/ m2) aged 20-30 years. The controls were 50 normal pre-pregnancy weight women with
(BMI 18.5 - 24.9 Kg/ m2) matched with cases as regards age and gestational age. Data were gathered from women who delivered in addition to their caring obstetricians involved as well as reviewing the medical records. Laboratory investigations included assessment of lipid profile (serum cholesterol, and serum triglycerides) at the time of delivery. Also, leptin hormone was measured in serum of patients using DRG Leptin (Sandwich) ELISA (EIA-2395) USA.
Results: Caesarean section rate was significantly higher among obese women (82% versus 30%; P<0.001).
The mean serum leptin concentration was significantly higher in obese women (BMI>30 kg/m2)
than normal weight controls (p= 0.013). Neonates born to obese had a statistically significant increased
birth weight than infants of normal weight participants (P=0.0001). Additionally, neonates born to
obese women had an increased risk of admission to Neonatal Intensive Care Unit OR (4.1), 95% (CI) 1.2 -2.4, p<0.001.
Conclusion: Obesity is associated with increased adverse maternal and perinatal complications.
INTRODUCTION
Obesity is a worldwide epidemic disease.(1) It is a leading preventable cause of death worldwide, with increasing prevalence in adults and children. Authorities view it as one of the most serious public health problems of the 21st century.(2) In Egypt, the prevalence of obesity is increasing according to Egyptian Demographic and Health Survey "EDHS" 2005. Obese women represent 47% of all females in reproductive age (15-49 years).(3) Extreme obesity is common in more than 52% among pregnant women in Saudi Arabia.(4)
Obesity has a deleterious effect on the mother
and foetus. In pregnancy, obesity increases the
risk for gestational diabetes, insulin resistance syndrome, and preeclampsia. It is also associated with increased risk of recurrent miscarriage in the first trimester and abruption placenta in late pregnancy.(5)
Body mass index (BMI) is an accurate reflection of body fat percentage in the majority of the adult population. BMI is calculated by dividing the subjects mass by the square of his or her
height, typically expressed in metric (Metric:
BMI = Kilograms/ meters2). A body mass index
of about 30 is roughly equivalent to 30% excess body weight the point at which excess mortality begins.(6)
Correspondence to: Dr Nermeen El Beltagy,
Department Obstetrics and Gynaecology, Faculty
of Medicine Alexandria University, Tel: +20101551161, E-mail: [email protected]
Leptin is a polypeptide hormone that helps in the regulation of body weight and energy regulation, and is linked to a variety of reproductive process. Interactions of leptin with mechanisms regulating pre-eclampsia and maternal diabetes and intrauterine growth retardation have been suggested.(7)
The aim of this study was to compare lipid profile and foetal outcome in obese pregnant females to non obese women delivered in El-Shatby Maternity University hospital.
METHODS
This study is a case control study of women registered at El Shatby Maternity University Hospital at the time of delivery in the period between June 2009 and June 2010. Cases were 50 obese prepregnant weight women (BMI> 30Kg/ m2) aged 20-30 years. Controls were 50 normal pre-pregnancy weight women with (BMI 18.5 - 24.9 Kg/ m2) matched with cases as regard age and gestational age. Gestational age at delivery was based upon the date of last regular menstrual period confirmed by ultrasonographic measurement of biparietal diameter and femur length. After approval of the local ethics committee an informed consent was obtained from each pregnant woman before inclusion in the study. The BMI was calculated using self reported weight and height from the patients at the time of delivery. Abdominal ultrasound using biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and femur length (FL) were done to assess foetal weight, and biophysical profile scoring. The machine used was CHISON 600 A. Neonatal examination included Apgar score and neonatal weight to assess newborn condition and incidence of admission to Neonatal Intensive Care Unit. Data were collected using delivery and newborn
medical records. Laboratory investigations included assessment of lipid profile (serum cholesterol, and serum triglycerides) at the time of delivery. Also, leptin hormone was measured in serum of patients using DRG Leptin (Sandwich) ELISA (EIA-2395) USA.(8)
Independent samples t-test was used as a parametric test of significance for comparison between two sample means, after performing the Leven's test for quality of variance. Chi-square (X2) was used to assess differences for qualitative variables. A level of significance equal to 0.05 was used to determine statistical significance.
RESULTS
A case control study included 50 obese pregnant females aged 20-30 years with a full term pregnancy were matched for age and gestational age with 50 non obese controls. Table I shows a significant difference in BMI between obese women and non obese control (p =0.001). Table II shows that caesarean section rate was significantly higher among obese women (82% versus 30%; P=0.001).
Table II illustrates that serum leptin concentrations were statistically significant higher in obese women than normal weight controls (P= 0.013). The serum levels of leptin in obese women were ranged from 13-155 mg/dl with a mean of 46.93 32.76. But, among non obese women serum leptin levels were ranged from 10-85 mg/dl with a mean of 29.9314.68.
Table II also shows the comparison between the two studied groups regarding the lipid profile. The serum level of cholesterol were ranged from 158 -529 mg/dl among obese women and 63-230 mg/dl in non obese controls with a mean of 379.04 91.97 and 150.8842.00 respectively. Serum cholesterol levels were statistically significant higher among obese women than the control (P=0.001). Obese cases had statistically significant higher levels of serum triglycerides than the control group. (P=0.0021) table II.
Obese women had more adverse maternal complications such as hypertension and diabetes than controls (hypertension was found in 50% of obese cases versus 32% of their counteracts. Diabetes was diagnosed in 30% of obese cases versus 10 % among non obese women (P<0.0001& 0.002 respectively) table III.
Table IV shows that infants born to pregnant obese women had a statistical significant higher APGAR score at one minute (P=0.004), but there were no statistical significant differences between neonates born to cases and control regarding APGAR score at 5 minute(p=0.42). Neonates born to obese cases had a statistically significant increased birth weight than infants of normal weight participants (P=0.0001) table IV. Additionally, neonates born to obese women had more than four folds increased risk of admission to NICU as OR (4.3), 95% (CI) 1.2 -2.4, p=0.001.
Table I: Demographic characteristics of obese cases and non obese control
Characteristics
obese pregnant
(n=50)
Non obese pregnant
(n=50)
p
Maternal age(y)
27.46± 3.05
27.98 ± 3.58
0.22 NS
BMI (kg/m2)
32.98 ± 1.35
22.81 ±0.82
0.001*
Weeks of gestation at delivery
± 0.81
38.94 ±1.37
0.28 NS
Data are shown as mean ± SD. BMI: body mass index
*significant NS: not significant
Table II: Comparison of Serum lipid profile and Leptin concentration, mode of delivery
between obese and non obese pregnant women
Characteristics
obese pregnant
(n=50)
non obese pregnant
(n=50)
P
Serum Leptin(mg/dl)
46.93±32.76
29.93±14.68
0.013*
Cholesterol(mg/dl)
379.04±91.97
150.88±42
0.001*
Triglycerides(mg/dl)
262.28±93
106.06±39.7
0.0021*
Mode of delivery
Vaginal
Caesarean
9 (18%)
41(82%)
35 (70%)
15 (30%)
0.001*
Data are shown as mean ± SD.
*significant
Table III: Comparison between pregnant obese non obese according
to maternal complication
Maternal
complication
obese pregnant
(n=50)
non obese pregnant
(n=50)
P
n
%
n
%
Hypertension
Diabetes
25
15
50.0
30.0
16
5
32.0
10.0
<0.001*
0.002*
*significant
Table IV: Comparison of Apgar score, admission to NICU and foetal weight between obese
and non obese pregnant women
Obese pregnant
(n=50)
non obese pregnant
(n=50)
OR (95% CI)
p
Apgar score at 1 minute
6.64±1.102
7.20±.782
0.004*
Apgar score at 5 minute
Foetal admission to NICU
9.14±.990
4 (8%)
9.28±.730
1 (2%)
4.3(1.2-2.4)
0.42 NS
0.001*
Foetal weight(gm)
3518.20±460.380
2919.80±436.472
0.0001*
Data are shown as mean ± SD.
*significant
NS: not significant
DISCUSSION
In the present study caesarean section rate
was significantly higher among obese women
(82% versus 30% in the normal weight control.
Our results were similar to a study done by
Doherty et al.(9) This finding might be explained
by the work of Poobalan et al,(10)who proposed
that deposition of pelvic fat causing obstruction
to the birth passage; poor myometrial contractility and consequent dysfunctional labour in obese women have all been identified as underlying mechanisms and pathogenesis for increased risk of caesarean delivery. Also, another cohort study of
Abdenhaimet al (11) revealed that caesarean sections were found to be increasingly more common with increasing BMI categories.
It has been evidenced in the present study that cases of BMI>30 had more maternal complication
of hypertension and diabetes than normal weight controls. Similarly, Herring(12) in his study demonstrated that maternal obesity is associated with an alarmingly high incidence of medical complications and increased level of obstetric interventions.
In this study, the serum leptin level showed an increase with the degree of BMI. Our results conforms with the study of Erturk, et al.(13) Other studies found that liptin has an inhibitory effect on spontaneous as well as induced uterine contractions. This lead to the proposed theory that leptin may be the cause of dysfunctional labor in obese women leading to increased caesarean section rates.(14) In this study, the mean foetal weight was significantly higher in obese women in comparison to controls. Findings of other studies confirm this association. they found that both obese and morbidity obese patients have a significantly increased risk for birth weight greater than 4000g compared with controls
(OR= 1.7).(11,15) Neonates born to obese women had an increased risk of admission to NICU. Our results were similar to a cohort study conducted in Saudi Arabia by El-Gilany and Hammad in 2010.(4)
One of this study limitation was the lack of assessment of length of hospital stay among obese women which can reflect the needed cost for health care of obese women. Also, Pre pregnancy or early pregnancy maternal BMI on admission sheet of Egyptian maternity hospitals should be recorded.
