|Year : 2022 | Volume
| Issue : 4 | Page : 225-229
Changes in birthweights and perinatal mortality rate in a rural block in South India over 30 years
Anne George Cherian, Jackwin Sam Paul, Vinod Joseph Abraham, Venkata Raghava Mohan, Jasmin Helan Prasad, Kuryan George
Department of Community Health, Christian Medical College and Hospital, Vellore, Tamil Nadu, India
|Date of Submission||12-May-2022|
|Date of Decision||25-Jun-2022|
|Date of Acceptance||29-Jun-2022|
|Date of Web Publication||17-Oct-2022|
Dr. Anne George Cherian
Department of Community Health, Christian Medical College, Vellore, Tamil Nadu
Source of Support: None, Conflict of Interest: None
Background: Perinatal mortality rate (PMR) includes both fetal deaths and deaths occurring during the 1st week of life. Low birthweight (LBW) continues to be a significant problem with 14.6% of all births globally and 20% of all births in India being LBW. There is a powerful association between birthweight and perinatal mortality. This study looks at data from a rural block in South India to understand the trends, possible reasons, and strategies for interventions. Methodology: Information regarding 80,206 pregnancies who were registered in the community health and development (CHAD) program between January 1986 and December 2018 was obtained from the CHAD health information system. Trends regarding birthweight, gestational age, and perinatal mortality were extracted from this system and analyzed. Results: Among the 69,386 babies whose birthweights were recorded, 16.7% were LBW (<2.5 kg). The PMR has steadily declined from 45.2/1000 live births in the period 1986–1990 to 14.3/1000 live births during the period 2016–2018. The mean birthweight has shown a steady rise over the years from 2.73 kg in 1986–1990 to 2.9 in 2016–2018. The mean standard deviation height of the mother has gone up from 152.3 cm (5.4) between 1986–1990 and 156.3 cm (5.7) in the 2016–2018 period. The proportion of anemic women (hemoglobin <11 g/dL) in 1986–1990 was 46.4% and had drastically come down to 23.8% in 2016–2018. Conclusion: The decreasing PMR may be attributed to the increasing birthweight which may, in turn, be related to better nutritional status of mothers which is evident in the increased height and decreased proportion of anemic women.
Keywords: Birthweights, perinatal mortality, South India
|How to cite this article:|
Cherian AG, Paul JS, Abraham VJ, Mohan VR, Prasad JH, George K. Changes in birthweights and perinatal mortality rate in a rural block in South India over 30 years. Curr Med Issues 2022;20:225-9
|How to cite this URL:|
Cherian AG, Paul JS, Abraham VJ, Mohan VR, Prasad JH, George K. Changes in birthweights and perinatal mortality rate in a rural block in South India over 30 years. Curr Med Issues [serial online] 2022 [cited 2022 Dec 6];20:225-9. Available from: https://www.cmijournal.org/text.asp?2022/20/4/225/358642
| Introduction|| |
Perinatal mortality refers to the death of a fetus or a neonate during 1st week of life and reflects the quality of prenatal, intrapartum, and newborn care. It is widely used as an indicator for international comparisons, and within countries and regions to estimate temporal trends. Since perinatal mortality rate (PMR) includes both fetal deaths and deaths occurring in the 1st week of life, it avoids conflicting judgments as to whether a fetus exhibited signs of life at birth and variations in prevalent practices which could lead to misclassification. Early neonatal deaths (ENDs) respond quickly to programmatic interventions, such as the WHO Essential Newborn Care Package, while stillbirths decline less rapidly as they are dependent more on interventions that primarily influence maternal health.
Globally, it is estimated that about 2.6 million stillbirths and 2.9 million neonatal deaths occur each year. Ending preventable perinatal deaths is high on the international public health agenda. Globally, the neonatal mortality rate fell by 49% from 37 deaths per 1000 live births in 1990–2018 to 18 in 2017.
With the birth of 25 million children each year, India accounts for nearly one-fifth of the world's annual childbirths. Nearly 40% of neonatal deaths happen during labor or the first 24 h after birth. Prematurity (35%), neonatal infections (33%), birth asphyxia (20%), and congenital malformations (9%) are among the major causes of newborn deaths. Nearly 3.5 million babies in India are born too early; 1.7 million babies are born with birth defects.
Low birthweight (LBW) continues to be a significant problem with 14.6% of all births globally and 20% of all births in India being LBW., LBW is defined as a birthweight of <2.5 kg. LBW babies are more likely to die in the 1st month of life and those who survive often develop life-long complications such as stunted growth, lower IQ, and chronic adult-onset conditions such as diabetes and obesity. There is a powerful association between birthweight and perinatal mortality. This could be partially attributed to the association between prematurity and LBW. It was previously presumed that babies were LBW due to their prematurity. However, all small babies are not premature, and all premature babies are not small.
The infant mortality rate tends to be higher in the population with a higher rate of preterm deliveries. This was elegantly illustrated in a study comparing the United States and Norway where it was found that the higher rate of perinatal deaths in the US was due to excess preterm deliveries. If the US could decrease these preterm births, they could bring down the PMR down to that seen in Norway. In contrast, if two populations of babies have different distributions of birthweight alone without a commensurate change in gestation, there is no predictable difference in their infant mortality. Populations with lighter babies do not necessarily have worse mortality. An example of this is the Mexican American babies who have lower weights compared to US white babies but a better overall survival. This may suggest that gestational age is a better predictor of Infant mortality than birthweight.
These data from three decades highlight trends, explore reasons, and postulate strategies that have worked in the community with a potential application to cohorts elsewhere as well.
| Methodology|| |
Kaniyambadi, a rural developmental block in Vellore district of Tamil Nadu comprises a mostly rural population of about 116,454 (2020) in 82 villages of Tamil Nadu, South India. In addition to the regular health care provided by the public health system, primary and secondary health care services for these villages are being provided by the Community Health and Development (CHAD) program of Christian Medical College, Vellore. Basic health care in the villages is provided by part-time community health workers under the supervision of health aides, who in turn are supervised by community health nurses. Monthly mobile clinics are conducted in each village by a doctor-led team and offer antenatal, immunization, and other clinic-based services. High-risk pregnancies identified at the mobile clinics are referred to the weekly high-risk clinic at the secondary level CHAD hospital. Residents of Kaniyambadi block access free hospital services from government institutions and also paid services from private hospitals, including the CHAD Hospital (located within Kaniyambadi and offering subsidized services to those with a lower socioeconomic status), and other private facilities in the nearby town (including Christian Medical College, a tertiary care facility).
The CHAD program in Kaniyambadi includes a demographic surveillance system which has been operational in this block. Surveillance of perinatal processes and outcomes is carried out through the same four-tiered system that delivers health services. Kaniyambadi is divided into regions with specific personnel in charge of health services and surveillance. Every week the community health workers report (orally) to the health aide about pregnancies, deliveries, births, deaths, morbidity, marriages, immunization, and couples eligible for contraception in the village. This information is tabulated by the health aide on standardized forms and verified by the nurse on her fortnightly visit to the village and subsequently by the area doctor. Information on migration into and out of the villages is also obtained on a periodical basis. The reports provided by the health aide are entered into a computerized Database, which provides bi-weekly outputs to health aides (regarding pregnant women due for tetanus immunization and children due for immunization) and monthly and annual reports to managers.
Completeness of birth information is assured because the community health workers are resident in the villages and because of the frequent visits of CHAD program personnel to the villages in Kaniyambadi. Since its inception, this system and infrastructure have provided information for several studies. This study included information on all births in Kaniyambadi from 1986 to 2018. For all the deaths including still births and ENDs, verbal autopsies are conducted by the health aides and coded using the International Classification of Diseases 9 classification.
Basic and comprehensive emergency obstetric and neonatal care are available in the 140 bedded CHAD hospital which is a secondary care hospital, where obstetric scans and laboratory services are also available. About 60% of the women in Kaniyambadi block deliver in CHAD. Hospital deliveries are also followed up by the health aides and records are maintained in the health information system (HIS). The crude birth rate in this block is 12.2/1000 population with an LBW percentage of 14.2%.
This was nonconcurrent cohort study.
Information regarding 80,206 pregnancies who were registered in the CHAD program between January 1986 and December 2018 was obtained from the CHAD HIS.
All data were anonymized before accessing it and the ethics committee waived the informed consent as the study was a retrospective study. Trends regarding the birthweight, gestational age, and perinatal mortality were extracted from this system and analyzed.
Continuous variables were expressed as mean standard deviation (SD) and categorical variables were expressed as frequencies (%). The data were stratified into 5-year intervals and PMR were calculated period wise. PMR was also classified based on gestational age.
This study was approved by the Institutional Review Board and Ethics Committee of the Christian Medical College, Vellore (IRB Min No. 13684 [Retro] dated December 16, 2020).
| Results|| |
There was a total of 80,206 pregnancies recorded for the period 1986–2018. Those whose gestational age at delivery was <28 weeks or where the outcome was recorded as abortion were excluded from the analysis. 76,570 deliveries were included in further analysis. The data between 1986 and 2018 were divided into seven 5 yearly periods (1986–1990, 1991–1995, 1996–2000, 2001–2005, 2006–2010, 2011–2015, 2016–2018). The first two periods included 17% each of the total deliveries included in the analysis. The proportion of deliveries per each 5-year period decreased gradually. The 6th period between 2011 and 2016 includes only 13.5% of the total deliveries indicating a decrease in the number of births in this block.
Among the pregnancies 30,989 (40.5%) were primigravida, 26,579 (34.7%) were the second gravida and 19,002 (24.8%) had more than two previous pregnancies.
Among the 76,570 pregnancies, 7184 did not have a recorded birthweight and had to be excluded from the analysis of birthweight and its effects. Among the 69,386 babies whose birthweights were recorded, 16.7% were LBW (<2.5 kg) and 0.7% of the babies had macrosomia (>4 kg). Majority of the births (44.8%) fell in the category of 2.5–2.99 kg
followed by 30.5% in the category 3.0–3.49 kg. The proportion of low-birth-weight infants has decreased temporally over the study periods. [Figure 1] shows the distribution of birthweights over the years.
[Figure 2] shows the distribution of births at different gestational ages. There has been a slight increase in the proportion of births at term.
The PMR has steadily declined from 45.2/1000 live births in the period 1986–1990 to 14.3/1000 live births during the period 2016–2018.
Birthweight-specific perinatal mortality rate by time period
There has been no significant decline in PMR in children born with birthweight <1 kg [Table 1]. In the 1–1.4 kg group and the 1.5–1.9 kg group, the PMR has only marginally reduced. The most dramatic decline has been in the weight category 2.0–2.4 kg where the PMR has declined from 40 in 1986–1990 to 11 in 2016–2018. Among children with normal birthweight, the perinatal mortality has almost halved.
|Table 1: Perinatal mortality rate in different birthweight categories over different time periods|
Click here to view
Gestational age-specific PMR has come down dramatically over the years in gestational ages over 34 weeks [Table 2]. However, this has not been such a big difference in the more premature babies. The mean birthweight has shown a steady rise over the years from 2.73 kg in 1986–1990 to 2.9 in 2016–2018. There has also been a gradual change in the height of the mothers. The mean (SD) height of the mother has gone up from 152.3 cm (5.4) between 1986–1990 and 156.3 cm (5.7) in the 2016–2018 period [Figure 3].
|Table 2: Perinatal mortality rate in different gestational age categories over different time periods|
Click here to view
The proportion of anemic women (hemoglobin <11 g/dL) in 1986–1990 was 46.4%. The prevalence had drastically come down to 23.8% in 2016–2018 [Figure 4].
|Figure 4: Change in proportion of women who were anemic during the study.|
Click here to view
| Discussion|| |
The decline in perinatal mortality over the last 30 years is quite impressive from 45.2/1000 births in 1986–1990 to 14.3/1000 births in 2016–2018. This impressive decline in overall Perinatal mortality has occurred without a substantial diminution in the birthweight-specific or gestational age-specific perinatal mortality, especially among the preterm or LBW babies. However, the decline in the perinatal mortality among normal birthweight and children between 2.0 and 2.4 kg at birth has been dramatic. A modest decrease in PMR among children heavier than 2.0 kg at birth has translated into a decline in the overall perinatal mortality despite the not-so-impressive decline among the lighter children. Reduction in birthweight-specific mortality can be accomplished by better quality medical care. The decline in PMR has been accompanied by an increase in mean birthweight, maternal height, and proportion delivering at term. The increase in the stature of the mother is likely to be of a long-term nature and may be attributed to better nutrition in childhood and adolescence for girls. A more aggressive high-risk approach may also contribute to the birth of larger babies. However, there are different causes of LBW. When different mechanisms that affect fetal growth come into play, the consequence will be different than when the fetus has a smaller body size due to the smaller body size norm in a specific population. In the 1st year of life, LBW babies are typically 20 or more times, likely to die than heavier babies.
Several environmental as well as maternal biological factors are likely to improve perinatal mortality. Socio-economic status, maternal cigarette smoking, quality of health care, and consanguinity are some of the factors which could explain the elevated PMR. Perinatal mortality has been seen to be higher among Asians even when compared to others residing in the same country. The high perinatal mortality among Asians has been ascribed to poor social-economic status, high maternal parity and age, poor maternal nutrition and health, low fetal birth weight, and higher rates of congenital malformation. The second-generation Asians in one of the studies seem to have successfully eliminated one of these high-risk factors by increasing fetal birthweight. This should contribute to a lowering of perinatal mortality.
A study in the Gambia showed that if chronically undernourished women were given dietary supplements there was a reduction in intrauterine growth restriction with a substantial reduction in the prevalence of stillbirths and early neonatal mortality. This contrasts with another study in Norway where they compared birthweights and perinatal survival of various ethnic groups. Birthweight differences in these groups were not clearly related to perinatal mortality. The significantly elevated mortality among the Pakistanis was attributable, in part, to the larger proportion of small births. In addition, the higher weight-specific mortality along the entire spectrum of adjusted birthweights for Pakistani infants indicated an increased risk regardless of birthweight. This leads to the question as to how important birthweight is when looking at perinatal mortality. Birthweight may be one of the contributing factors in bringing down the perinatal mortality but may not be the only factor.
The decline in perinatal mortality has been encouraging and can be attributed to various factors such as increased institutional deliveries and better obstetric care. However, the fact that the decline in birthweight-specific and gestation-specific PMR is not as impressive as the decline in the overall rate suggests that improvement in hospital/clinical care may not be as important as long-term changes in the nutrition of the pregnant mothers.
The limitations of this study are its retrospective nature. The findings from this study still do provide us with insight into the probable causes for decrease in PMR and the need for further prospective cohort studies to investigate this further.
| Conclusion|| |
It is possible that the increased mean birthweight may contribute in a large way to diminution of the overall perinatal mortality. The improved nutritional status of young and adolescent girls leading to an increase in their height could potentially lead to increased birthweight of the newborn babies thus contributed to decreasing perinatal mortality. It is important to invest in the nutritional support of the girl child and in better antenatal care for women as this will eventually mean healthier newborn babies. A better understanding of the contribution of birthweight and gestational age at delivery to perinatal mortality is needed to make these decisions.
Research quality and ethics statement
All authors of this manuscript declare that this scientific study is in compliance with standard reporting guidelines set forth by the EQUATOR Network. The authors ratify that this study required Institutional Review Board/Ethics Committee Review, and hence prior approval was obtained (IRB Min No. 13684 [Retro] dated December 16, 2020). We also declare that we did not plagiarize the contents of this manuscript and have performed a plagiarism check.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Bharati P, Pal M, Bandyopadhyay M, Bhakta A, Chakraborty S, Bharati P. Prevalence and causes of low birth weight in India. Malays J Nutr 2011;17:301-13.
Wilcox A, Skjaerven R, Buekens P, Kiely J. Birth weight and perinatal mortality. A comparison of the United States and Norway. JAMA 1995;273:709-11.
Wilcox AJ. On the importance– and the unimportance– of birthweight. Int J Epidemiol 2001;30:1233-41.
Buekens P, Notzon F, Kotelchuck M, Wilcox A. Why do Mexican Americans give birth to few low-birth-weight infants? Am J Epidemiol 2000;152:347-51.
George K, Prasad J, Singh D, Minz S, Albert DS, Muliyil J, et al
. Perinatal outcomes in a South Asian setting with high rates of low birth weight. BMC Pregnancy Childbirth 2009;9:5.
Arntzen A, Moum T, Magnus P, Bakketeig LS. Marital status as a risk factor for fetal and infant mortality. Scand J Soc Med 1996;24:36-42.
Tuthill DP, Stewart JH, Coles EC, Andrews J, Cartlidge PH. Maternal cigarette smoking and pregnancy outcome. Paediatr Perinat Epidemiol 1999;13:245-53.
Clarke M, Clayton DG. Quality of obstetric care provided for Asian immigrants in Leicestershire. Br Med J (Clin Res Ed) 1983;286:621-3.
Influence of Consanguinity and Maternal Education on Risk of Stillbirth and Infant Death in Norway, 1967–1993 | American Journal of Epidemiology | Oxford Academic. Available from: https://academic.oup.com/aje/article/148/5/452/76938
. [Last accessed on 2019 Oct 29].
Clarke M, Clayton DG, Mason ES, MacVicar J. Asian mothers' risk factors for perinatal death – The same or different? A 10 year review of Leicestershire perinatal deaths. BMJ 1988;297:384-7.
Dhawan S. Birth weights of infants of first generation Asian women in Britain compared with second generation Asian women. BMJ 1995;311:86-8.
Ceesay SM, Prentice AM, Cole TJ, Foord F, Weaver LT, Poskitt EM, et al
. Effects on birth weight and perinatal mortality of maternal dietary supplements in rural Gambia: 5 year randomised controlled trial. BMJ 1997;315:786-90.
Vangen S, Stoltenberg C, Skjaerven R, Magnus P, Harris JR, Stray-Pedersen B. The heavier the better? Birthweight and perinatal mortality in different ethnic groups. Int J Epidemiol 2002;31:654-60.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2]