Risk Factors of Preterm Birth among Palestinian Women: Case Control Study

Research Article

Austin J Nurs Health Care. 2015;2(1): 1011.

Risk Factors of Preterm Birth among Palestinian Women: Case Control Study

Adnan Lutfi Sarhan RN1* and Heyam Ezat Anini RN2

1College of Nursing Science, Al-Ghad International Colleges for Applied Medical Sciences, Kingdom of Saudi Arabia

2Department of Mental health Nursing, School of Nursing, Capodistrian University of Athens, Greece

*Corresponding author: Adnan Lutfi Sarhan RN, College of Nursing Science, Al-Ghad International Colleges for Applied Medical Sciences, Al-Madinah Al-Monawarah, Kingdom of Saudi Arabia

Received: November 17, 2014; Accepted: January 05,2015; Published: January 07, 2015

Abstract

Introduction: Preterm birth is the delivery of an infant before 37 weeks of gestation. It is a major public health problem. Prematurity is the leading cause of infant mortality and morbidity worldwide. The purpose of this study is to identify the risk factors of preterm birth and possible determinants among Palestinian women in the Northern part of the West Bank.

Methodology: A case control study of 100 cases of preterm delivery and 201 controls of full term delivery was carried out. The cases were taken from three governmental hospitals in the Northern West Bank. The data was analyzed by using Statistical Package of Social Sciences (SPSS) version 19. Frequencies, Chi-square and multiple regressions were done to explore the relation between the dependent variable (preterm birth) and the other independent variables. The study took six months starting from the first of May 2013 to the 31 of October 2013. Face to face interviews using a questionnaire were used.

Result: The results show that the main risk factors of preterm birth are the following: medical indication for pregnancy termination, (p= 0.001), (95% CI 0.328- 0.617); Preterm Premature Rupture of Membrane (PPROM), (p=0.006), (95% CI 0.079- 0.462); previous history of preterm delivery, (p=0.007), (95% CI 0.049- 0.309); and disorders associated with pregnancy, (p= 0 .015), (95%, CI 0.028-0.254t). Other risk factors identified by the study are the following: type of family, congenital gynecological problems, family history of preterm birth, previous delivery by Caesarean Section (CS), daily, vaginal bleeding during pregnancy, psychological problems, and height.

Conclusion: The main risk factors of preterm birth were multiple pregnancies, medical indications for preterm birth (mainly preeclampsia), placenta previa, abruption placenta, previous Caesarean Section, the presence of a disorder associated with pregnancy (mainly hypertensive disorder), preterm premature rupture of membrane, and a previous history of preterm birth.

Keywords: Pregnancy; Labour; Female; Premature birth; Preterm labour

Abbreviations

ABGAR: Appearance Pulse Grimace Activity Respiration; CS: Caesarean Section; IMR: Infant Mortality Rate; IPTB: Indicated Preterm Birth; IVF: Invetro- Fertilization; LMP: last Menstrual Period; NIS: New Israeli Shekel; PPROM: Preterm Premature Rupture Of Membrane; PTB: Preterm Birth; RDS: Respiratory Distress Syndrome; SPSS: Statistical Package of Social Sciences; SPTB: Spontaneous Preterm Birth; UTI: Urinary Tract Infection

Introduction

Background

Despite advances in prenatal medicine, the incidence of preterm labour continuous to increase [1]. In Palestine the preterm services developed in acceptable situation, but still the preterm care going to increase. Preterm labour continues to be one of the main causes of neonatal mortality and morbidity. It refers to labour with an onset before 37 weeks gestation. This is essentially an arbitrary lower cut-off for a ‘term’ pregnancy and there is clearly a big difference between labour at 27 weeks gestation and labour at 36 weeks and 6 days. From an epidemiological perspective it is possible to evaluate exposures (potential risk factors) and outcomes (morbidity or mortality) on a gestational week-by-week basis and this approach offers certain statistical advantages [2]. Most preterm babies have long life impairment and impose a significant economic burden on society [3]. Prematurity, whether examined by gestational age or birth weight is associated with significant neonatal cost, which is decreased with advancing gestational age. The total cost for each gestational age group from 25 – 36 weeks was $38 million in United States. The financial burden of the acute care of preterm infants has been estimated to be at least 26.2 billion per year also in United States [4]. Most of the risk factors for preterm birth are modifiable: socioeconomic, smoking, maternal stress, lack of prenatal care and iatrogenic preterm birth. So the identification of modifiable risk factors is an essential first step in any primary prevention program [3]. The basic mission in identifying risk factors is to improve the health of infants by preventing premature birth and decreasing infant mortality rates. By improving community services, education and undertaking advocacy lives can be saved.

The Palestinian community has an overall low socioeconomic standing [5]. Many Palestinians live below the poverty line and all live under occupation. These conditions make Palestinian women suffer from a lack of health services. Additionally, the number of neonatal units and incubators is not enough to accommodate the number of premature babies arriving daily in Palestine. Many preterm deliveries occur in hospitals without neonatal units, and the transferring process is difficult and time consuming due to the restriction of movement imposed by Israeli authorities. This affects the baby’s condition and increases infant morbidity and mortality rates. Thus, preventing premature births in paramount in Palestine considering the existence of these additional factors of vulnerability. In order to be effective, preventative measures must be supported by high quality research in the Palestinian community. Researchers must be supported financially by the government and the Ministry of Health. The aim of this study is to identify the risk factors of preterm birth and possible determinants among Palestinian women in the Northern part of the West Bank.

Methods

Study design

The type of this study is a hospital-based comparative study by choosing one case and two controls with a ratio of 1:2. Cases were composed of the respondents who had (preterm delivery) and control respondents who had the condition (full term delivery).

Study population

The study population consisted of women who had recently given birth and their infants. For every premature delivery (a case) two fullterm deliveries were taken as a control. For each premature baby (a case), two full term babies were chosen a control. Approximately 6,400 deliveries were enrolled in the study over six months. The distribution of deliveries was 2,885 from Rafidia Hospital; 1,040 deliveries from Al-Shaheed Thabet hospital and 2,482 deliveries from Al-Shaheed Ali hospital. The period of the study was six months. It started from the first of May 2013 to thirty-first of October 2013.

Criteria for inclusion of participants in the study

Inclusion criteria for cases

The inclusion criteria for cases were a live preterm birth during the period from the first of May 2013 to the thirty-first of October 2013. The gestational age inclusion criteria for cases were from 27 weeks to 36 weeks and 6 days according to the last Menstrual Period (L.M.P.). Gestational age was calculated by Nagles rule (L.M.P plus seven days to minus three months). The 27 weeks were used as a lower limit because the birth record registration in governmental hospitals is 27 weeks. The inclusion criterion for the control group was a fullterm delivery, from 37 weeks of gestation to 41 weeks.

Exclusion criteria for cases and controls

Still birth, unknown L.M.P, less than 27 weeks of gestation for cases and more than 41 weeks of gestation for controls, and congenital abnormal babies.

Sampling process

Weekly visits to the three governmental hospitals were made. All cases of premature delivery presented at the hospital that day were taken as cases. Controls were chosen by taking the next two beds of full term delivery available at hospital. If they did not meet the inclusion criteria the next bed was taken.

Data collection process

Primary data were collected through highly structured interviews and questionnaires were filled by face to face interviews directly after delivery while the women were staying at the hospital. The researchers sat in front of the women, asked her the questions and ticked her answers. The questionnaire was prepared, organized and numbered with serial numbers, which were taken from a previous study done in the Gaza Strip. Necessary modifications for the questionnaire were done to be applicable for the current study and population. Also, the questionnaire was translated to Arabic language to be easier for use, and was designed around the risk factors of preterm birth; it contains seven parts. The first part contains personal information, the second part socioeconomic information, the third part contains past obstetrical and gynaecological information, the forth part contains current pregnancy information, the fifth part contains maternal physical information, the sixth part contains antenatal care information during pregnancy and the seventh part contains newborn information. Secondary data were taken from mothers’ files and birth records. These data are: women’s weight, height, and haemoglobin level before birth. Newborn information was taken from newborn files at the neonatal unit such as birth weight, Appearance Pulse Grimace Activity Respiration (ABGAR) score, and causes of admission to neonatal unit and period of admission.

Sample size

A convenient sample of 301 subjects was chosen, 100 cases and 201 controls. This sample size was chosen in limited number due to that the study was not funded which limited its results.

Reliability of the study

Reliable questionnaire with cronbach alpha 82%; was filled by face to face interviews with both cases and controls by the researcher. The questionnaire was used before in a study done in the Gaza Strip and checked for validity and reliability. A pilot study was done on 15 cases and ten controls to examine the internal consistency of the questionnaire by using test-retest reliability test. The necessary modifications of the questionnaire questions were done to be suitable for our population.

Statistical analysis

The data was analyzed by using (SPSS) version 19. Frequencies, Chi-square and multiple regressions were done to explore the relation between dependent variable (preterm birth) and the other independent variables.

Ethical considerations

A consent form was prepared on the first page of the questionnaire, and the participants’ agreement requested. If the participant could not read, the consent was read to her by the researcher. Also, the permission from the Institution Review Board at An-Najah National University was taken.

Results

Introduction

A hospital-based case control study was conducted in three governmental hospitals in three Palestinian cities at the Northern West Bank: Nablus, Jenin and Tulkarem. The study started on the first of May 2013 and ended on the 31st of October 2013. The aim of this study is to identify the risk factors of preterm birth among Palestinian women. Our anticipation from the study is that there were deferent risk factors for preterm birth. Preterm birth is mainly related to previous history of preterm delivery, family history, genitourinary tract infection, disorder caused by or associated with pregnancy such as pregnancy induced hypertension, preeclampsia and eclampsia, gyneobstetric conditions as uterine, cervical, and placental abnormalities as placenta previa and abruption placenta which are presented by massive ante partum haemorrhage that needs medical intervention and urgent caesarean section to save both mothers’ and babies’ lives. Chronic diseases associated with pregnancy like hypertension and diabetes were the most common causes of medically indicated preterm delivery. Additional preterm risk factors were multiple pregnancies, such as twins or triplets, who caused over distension of the uterus and resulted in preterm delivery, as well as maternal habits like smoking, and stressful life events. The aetiology of preterm delivery is multi factorial and the isolation of one factor from another is very difficult, and requires high quality research on the community.

Study findings

The main risk factors of preterm birth were found to be:

Table 1 contains main risk factors of preterm birth and Table 2 contains other risk factors. After analysis, five of these factors were found to be significant. Multiple pregnancy (p= 0.001), previous history of preterm birth (p=0.007), Preterm Premature rupture of membrane (p= 0.006), medical indications of preterm birth (p= 0.001) and a disorder associated with pregnancy (p= 0.0158).